Powered by Deep Web Technologies
Note: This page contains sample records for the topic "aqueous electrolyte modeling" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


1

Aqueous electrolyte modeling in ASPEN PLUS{trademark}  

SciTech Connect

The presence of electrolytes in aqueous solutions has long been recognized as contributing to significant departures from thermodynamic ideality. The presence of ions in process streams can greatly add to the difficulty of predicting process behavior. The difficulties are increased as temperatures and pressures within a process are elevated. Because many chemical companies now model their processes with chemical process simulators it is important that such codes be able to accurately model electrolyte behavior under a variety of conditions. Here the authors examine the electrolyte modeling capability of ASPEN PLUS{trademark}, a widely used simulator. Specifically, efforts to model alkali metal halide and sulfate systems are presented. The authors show conditions for which the models within the code work adequately and how they might be improved for conditions where the simulator models fail.

Bloomingburg, G.F. [Univ. of Tennessee, Knoxville, TN (United States). Dept. of Chemical Engineering]|[Oak Ridge National Lab., TN (United States); Simonson, J.M.; Moore, R.C.; Mesmer, R.E.; Cochran, H.D. [Oak Ridge National Lab., TN (United States)

1995-02-01T23:59:59.000Z

2

Aqueous Electrolyte Modeling in Aspen Plus G. E  

Office of Scientific and Technical Information (OSTI)

Aqueous Electrolyte Modeling in Aspen Plus Aqueous Electrolyte Modeling in Aspen Plus G. E Bloomingburg (1)(3), J. M. Simonson (2), R C. Moore (2), I€ D. Cochran (3), and R. E. Mesmer (2) (1) Department of Chemical Engineering The University of Tennessee Knoxville, Tennessee 37996-2200 (2) Chemical and Analytical Sciences Division Oak Ridge National Laboratory* Oak Ridge, Tennessee 37831-6110 (3) Chemical Technology Division Oak Ridge National Laboratory* Oak Ridge, Tennessee 37831-6224 Presented at the 12th International Conference on the Properties of Water and Steam Orlando, Florida September 14, 1994 The submitted manuscript has been authored by a contractor o f the US. Government under contract No. DE-ACOS-84OR21400. Accordingly, the US. Government retains a nonexclusive, royalty free license to

3

Mathematical Modeling of CO2 Reduction to CO in Aqueous Electrolytes...  

NLE Websites -- All DOE Office Websites (Extended Search)

CO2 Reduction to CO in Aqueous Electrolytes, II Study of an Electrolysis Cell Making Synagas (CO + H2) from CO2 and H2O Reduction at Room Temperature Title Mathematical Modeling of...

4

Models for aqueous electrolyte mixtures for systems extending from dilute range to the fused salt: Evaluation of parameters to high temperatures and pressures  

DOE Green Energy (OSTI)

Models based on general equations for the excess Gibbs energy of the aqueous fluid provide thermodynamically consistent structures for evaluating and predicting aqueous electrolyte properties. These equations yield other quantities upon appropriate differentiation, including osmotic and activity coefficients, excess enthalpies, heat capacities, and volumes. For this reason a wide array of experimental data are available from which model parameters and their temperature or pressure dependence can be evaluated. For systems of moderate concentration, the most commonly used model at present is the ion-interaction approach and coworkers. For more concentrated solutions, including those extending to the fused salt, an alternate model based on a Margules-expansion and commonly used for nonelectrolytes was proposed. We discuss these two models and give examples of parameter evaluations for some geologically relevant systems to high temperatures and pressures; also we show applications of the models to calculations of solubility equilibria.

Pabalan, R.T.; Pitzer, K.S.

1988-09-01T23:59:59.000Z

5

Great Plains ASPEN model development: development of a model for the density of solutions of aqueous electrolytes. Final topical report. [Extension of Debye-Huckel limiting law  

SciTech Connect

A new physical property model for the calculation of the density of solutions of aqueous electrolytes has been developed for the ASPEN process simulator as part of the simulation of the Great Plains Coal Gasification Plant. The model developed recently by Jay S. Dweck, Consultant, Inc. is an extension of the Debye-Huckel limiting law. The Debye-Huckel limiting law allows the predictions of the density of dilute solutions of dissolved salts by providing a relationship for the molar volume of the salt as a function of ion strength. The relationship is linear in the square root of ionic strength, with the slope dependent only upon the charges of the ions which constitute the salt. When combined with data for the infinite dilution molar volume of the salts, solution density can be calculated. The new model preserves the linear relationship with the square root of ionic strength, but introduces ion dependent parameters for the determination of the slope. The solution density is calculated in terms of the molar volumes of the individual ions, instead of a mixture of pseudo salts. Preliminary tests of the model have shown it to be far more accurate than the original limiting law, and applicable to more concentrated solutions (greater than 10 molar).

Dweck, J.S.; Mendelson, M.A.; Blumenfeld, R.

1985-01-01T23:59:59.000Z

6

Low Cost Aqueous Electrolyte Based Energy Storage: Materials and ...  

Science Conference Proceedings (OSTI)

Presentation Title, Low Cost Aqueous Electrolyte Based Energy Storage: Materials and ... Deployment of New High Temperature Alloys for Power Generation Systems · Designing ... Materials Metrology for a Hydrogen Distribution Infrastructure.

7

Anion receptor compounds for non-aqueous electrolytes  

SciTech Connect

A new family of aza-ether based compounds including linear, multi-branched and aza-crown ethers is provided. When added to non-aqueous battery electrolytes, the new family of aza-ether based compounds acts as neutral receptors to complex the anion moiety of the electrolyte salt thereby increasing the conductivity and the transference number of LI.sup.+ ion in alkali metal batteries.

Lee, Hung Sui (East Setauket, NY); Yang, Xiao-Oing (Port Jefferson Station, NY); McBreen, James (Bellport, NY)

2000-09-19T23:59:59.000Z

8

Electrochemical investigation of the gallium nitride-aqueous electrolyte interface  

SciTech Connect

GaN (E{sub g} = {approximately}3.4 eV) was photoelectrochemically characterized and the energetic position of its bandedges determined with respect to SHE. Electrochemical impedance spectroscopy was employed to analyze the interface, determine the space charge layer capacitance, and, subsequently obtain the flatband potential of GaN in different aqueous electrolytes. The flatband potential of GaN varied at an approximately Nernstian rate in aqueous buffer electrolytes of different pHs indicating acid-base equilibria at the interface.

Kocha, S.S.; Peterson, M.W.; Arent, D.J.; Turner, J.A. [National Renewable Energy Lab., Golden, CO (United States). Photoconversion Branch; Redwing, J.M.; Tischler, M.A. [Advanced Technology Materials, Inc., Danbury, CT (United States)

1995-12-01T23:59:59.000Z

9

Highly Quantitative Electrochemical Characterization of Non-Aqueous Electrolytes & Solid Electrolyte Interphases  

DOE Green Energy (OSTI)

The methods to measure solid electrolyte interphase (SEI) electrochemical properties and SEI formation capability of non-aqueous electrolyte solutions are not adequately addressed in the literature. And yet, there is a strong demand in new electrolyte generations that promote stabilized SEIs and have an influence to resolve safety, calendar life and other limitations of Li-ion batteries. To fill this gap, in situ electrochemical approach with new descriptive criteria for highly quantitative characterization of SEI and electrolytes is proposed. These criteria are: SEI formation capacity, SEI corrosion rate, SEI maintenance rate, and SEI kinetic stability. These criteria are associated with battery parameters like irreversible capacity, self-discharge, shelf-life, power, etc. Therefore, they are especially useful for electrolyte development and standard fast screening, allowing a skillful approach to narrow down the search for the best electrolyte. The characterization protocol also allows retrieving information on interfacial resistance for SEI layers and the electrochemical window of electrolytes, the other important metrics of characterization. The method validation was done on electrolyte blends containing phosphazenes, developed at Idaho National Laboratory, as 1.2M LiPF6 [80 % EC-MEC (2:8) (v/v) + 20% Phosphazene variety] (v/v), which were targeted for safer electrolyte variations.

Sergiy V. Sazhin; Kevin L. Gering; Mason K. Harrup; Harry W. Rollins

2012-10-01T23:59:59.000Z

10

Phenyl boron-based compounds as anion receptors for non-aqueous battery electrolytes  

SciTech Connect

Novel fluorinated boronate-based compounds which act as anion receptors in non-aqueous battery electrolytes are provided. When added to non-aqueous battery electrolytes, the fluorinated boronate-based compounds of the invention enhance ionic conductivity and cation transference number of non-aqueous electrolytes. The fluorinated boronate-based anion receptors include different fluorinated alkyl and aryl groups.

Lee, Hung Sui (East Setauket, NY); Yang, Xiao-Qing (Port Jefferson Station, NY); McBreen, James (Bellport, NY); Sun, Xuehui (Middle Island, NY)

2002-01-01T23:59:59.000Z

11

Electric cell with a non-aqueous electrolyte  

Science Conference Proceedings (OSTI)

A secondary electric cell is described which includes: a non-aqueous electrolyte, a negative electrode whose active material includes at least one alkali metal in contact with the electrolyte, and a positive electrode whose active material is suitable for intercalating the active material of the negative electrode, wherein said positive electrode includes an active compound or solid solution whose general formula is Mxx, RyX3 where: M is an element chosen from lead and tin; R is an element chosen from bismuth and antimony; and X is an element chosen from sulphur and selenium, with X having a value lying between 0 and 1 (Inclusive), and Y having a value lying between 0 and 2 (Inclusive). Such cells may be used in watches or pacemakers.

Brec, R.; Dugast, A.; Le Mehaute, A.

1982-01-05T23:59:59.000Z

12

Electric cell with a non-aqueous electrolyte  

Science Conference Proceedings (OSTI)

An electric cell with a non-aqueous electrolyte. The cell includes a positive electrode whose active material is suitable for inserting the negative active material dynamically, a negative electrode whose active material includes at least one alkali metal, and an electrolyte, wherein said positive electrode includes at least one compound whose general formula is mx4rntp, where M represents an element chosen from among silicon, germanium, tin and lead, X represents sulphur, selenium or tellurium, R and T represent an element chosen from among copper, silver, manganese, iron, cobalt and nickel, N being greater than or equal to 0 and less than or equal to 4, P being greater than or equal to 0 and less than or equal to 2. The invention is used in connection with button type electric cells.

Le Blanc-Soreau, A.; Le Mehaute, A.; Rouxel, J.

1982-03-02T23:59:59.000Z

13

Implementation of equilibrium aqueous speciation and solubility (EQ3 type) calculations into Cantera for electrolyte solutions.  

SciTech Connect

In this report, we summarize our work on developing a production level capability for modeling brine thermodynamic properties using the open-source code Cantera. This implementation into Cantera allows for the application of chemical thermodynamics to describe the interactions between a solid and an electrolyte solution at chemical equilibrium. The formulations to evaluate the thermodynamic properties of electrolytes are based on Pitzer's model to calculate molality-based activity coefficients using a real equation-of-state (EoS) for water. In addition, the thermodynamic properties of solutes at elevated temperature and pressures are computed using the revised Helgeson-Kirkham-Flowers (HKF) EoS for ionic and neutral aqueous species. The thermodynamic data parameters for the Pitzer formulation and HKF EoS are from the thermodynamic database compilation developed for the Yucca Mountain Project (YMP) used with the computer code EQ3/6. We describe the adopted equations and their implementation within Cantera and also provide several validated examples relevant to the calculations of extensive properties of electrolyte solutions.

Moffat, Harry K.; Jove-Colon, Carlos F.

2009-06-01T23:59:59.000Z

14

Fluorinated Arylboron Oxalate for Non-Aqueous Battery Electrolytes  

A range of new fluorinated arylboron oxalate compounds for use as additives and anion receptors in lithium-based battery electrolytes have been ...

15

Microscopic Insights into the Electrochemical Behavior of Non-aqueous Electrolytes in Supercapacitors  

Science Conference Proceedings (OSTI)

Electric double-layer capacitors (EDLC) are electrical devices that store energy by adsorption of ionic species at the inner surface of porous electrodes. Compared with aqueous electrolytes, ionic liquid and organic electrolytes have the advantage of larger potential windows, making them attractive for the next generation of EDLC with superior energy and power densities. The performance of both ionic liquid and organic electrolyte EDLC hinges on the judicious selection of the electrode pore size and the electrolyte composition that requires a comprehension of the charging behavior from a microscopic view. In this perspective, we discuss predictions from the classical density functional theory (CDFT) on the dependence of the capacitance on the pore size for ionic-liquid and organic-electrolyte EDLC. CDFT is applicable to electrodes with the pore size ranging from that below the ionic dimensionality to mesoscopic scales, thus unique for investigating the electrochemical behavior of the confined electrolytes for EDLC applications.

Jiang, Deen [ORNL; Wu, Jianzhong [ORNL

2013-01-01T23:59:59.000Z

16

Optimization of non-aqueous electrolytes for Primary lithium/air batteries operated in Ambient Enviroment  

Science Conference Proceedings (OSTI)

The selection and optimization of non-aqueous electrolytes for ambient operations of lithium/air batteries has been studied. Organic solvents with low volatility and low moisture absorption are necessary to minimize the change of electrolyte compositions and the reaction between lithium anode and water during discharge process. It is critical to make the electrolytes with high polarity so that it can reduce wetting and flooding of carbon based air electrode and lead to improved battery performance. For ambient operations, the viscosity, ionic conductivity, and oxygen solubility of the electrolyte are less important than the polarity of organic solvents once the electrolyte has reasonable viscosity, conductivity, and oxygen solubility. It has been found that PC/EC mixture is the best solvent system and LiTFSI is the most feasible salt for ambient operations of Li/air batteries. Battery performance is not very sensitive to PC/EC ratio or salt concentration.

Xu, Wu; Xiao, Jie; Zhang, Jian; Wang, Deyu; Zhang, Jiguang

2009-07-07T23:59:59.000Z

17

Three dimensional electrode for the electrolytic removal of contaminants from aqueous waste streams  

DOE Patents (OSTI)

Efficient and cost-effective electrochemical devices and processes for the remediation of aqueous waste streams. The invention provides electrolytic cells having a high surface area spouted electrode for removal of heavy metals and oxidation of organics from aqueous environments. Heavy metal ions are reduced, deposited on cathode particles of a spouted bed cathode and removed from solution. Organics are efficiently oxidized at anode particles of a spouted bed anode and removed from solution. The method of this inventions employs an electrochemical cell having an anolyte compartment and a catholyte compartment, separated by a microporous membrane, in and through which compartments anolyte and catholyte, respectively, are circulated. A spouted-bed electrode is employed as the cathode for metal deposition from contaminated aqueous media introduced as catholyte and as the anode for oxidation of organics from contaminated aqueous media introduced as anolyte.

Spiegel, Ella F. (Louisville, CO); Sammells, Anthony F. (Boulder, CO)

2001-01-01T23:59:59.000Z

18

Electrodeposited Manganese Oxides on Three-Dimensional Carbon Nanotube Substrate: Supercapacitive Behaviour in Aqueous and Organic Electrolytes  

Science Conference Proceedings (OSTI)

Thin amorphous manganese oxide layers with a thickness of 3-5nm are electrodeposited on a carbon nanotube (CNT) film substrate that has a three-dimensional nanoporous structure (denoted asMnO2/CNT electrode). For the purpose of comparison, manganese oxide films are also electrodeposited on a flat Pt-coated Si wafer substrate (denoted as MnO2 film electrode). The pseudocapacitive properties of the MnO2 film and MnO2/CNT electrodes are examined in both aqueous electrolyte (1.0M KCl) and nonaqueousorganic electrolyte (1.0M LiClO4 in propylene carbonate). While both types of electrode showpseudocapacitive behaviour in the aqueous electrolyte, only the MnO2/CNT electrode does so in the organic electrolyte, due to its high oxide/electrolyte interfacial area and improved electron conduction through the CNT substrate. Compared with the MnO2 film electrode, the MnO2/CNT electrode shows a much higher specific capacitance and better high-rate capability, regardless of the electrolyte used.Use of the organic electrolyte results in a ?6 times higher specific energy compared with that obtained with the aqueous electrolyte, while maintaining a similar specific power. The construction of a threedimensional nanoporous network structure consisting of a thin oxide layer on a CNT film substrate at the nm scale and the use of an organic electrolyte are promising approaches to improving the specific energyof supercapacitors.

Nam,K.W.; Yang,X.

2009-03-01T23:59:59.000Z

19

High Rate Oxygen Reduction in Non-aqueous Electrolytes with the Addition of Perfluorinated Additives  

DOE Green Energy (OSTI)

The discharge rate capability of Li-air batteries is substantially increased by using perfluorinated compounds as oxygen carriers. The solubility of oxygen in a non-aqueous electrolyte can be significantly increased by the introduction of such compounds, which leads to the increase in the diffusion-limited current of oxygen reduction on the gas diffusion electrode in a Li-air battery. The perfluorinated compound is found to be stable within the electrochemical window of the electrolyte. A powder microelectrode and a rotating disk electrode were used to study the gas diffusion-limited current together with a rotating disk electrode. A 5 mA cm{sup -2} discharge rate is demonstrated in a lab Li-O{sub 2} cell.

Wang, Y.; Yang, X.; Zheng, D.; Qu, D.

2011-08-04T23:59:59.000Z

20

Investigation of the Gas-Diffusion-Electrode Used as Lithium/Air Cathode in Non-aqueous Electrolyte and the Importance of Carbon Material Porosity  

SciTech Connect

The gas-diffusion-electrode used in a Li-air cell has been studied in a unique homemade electrochemical cell. Three major obstacles for the development of a feasible Li-air system were discussed with a focus on the development of a functional gas-diffusion-electrode in non-aqueous electrolytes and the way of avoiding the passivation of gas-diffusion-electrodes caused by the deposition of the reduction products. It is the first time that the importance of establishing the 3-phase electrochemical interface in non-aqueous electrolyte is demonstrated by creating air-diffusion paths and an air saturated portion for an air cathode. A model mechanism of electrode passivation by the reaction products was also proposed. Lithium oxides formed during O{sub 2} reduction tend to block small pores, preventing them from further utilization in the electrochemical reaction. On the other hand, lithium oxides would accumulate inside the large pores during the reduction until the density of oxides becomes high enough to choke-off the mass transfer. Carbon materials with a high surface area associated with larger pores should be selected to make the gas-diffusion-electrode for Li-air battery. For the first time, a near linear relationship between the capacity of GDE in a non-aqueous electrolyte and the average pore diameter was demonstrated, which could be used to estimate the capacity of the GDE quantitatively.

Qu, D.; Yang, X.; Tran, C.

2010-04-02T23:59:59.000Z

Note: This page contains sample records for the topic "aqueous electrolyte modeling" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Parametric ARX Modeling of the Electrolytic Smelter Pot  

Science Conference Proceedings (OSTI)

The Anode effect that occurs in electrolytic smelter pot is responsible for gases such as PFC's. These gases contributeto the greenhouse effect, and in addition jeopardizes its productive capacity. From the voltage (output) and current(input) signals ... Keywords: Parametric Estimation, Transfer Function, ARX model, Parametric modeling of Dynamic Systems, Electrolytic Smelter Pot, System identification, Anode Effect

Antonio José da Silva; João Viana da_Fonseca Neto; Nilton Freixo Nagem

2009-03-01T23:59:59.000Z

22

Electrolyte  

Science Conference Proceedings (OSTI)

Table 2   Electrolytes for the electrochemical machining of various metals...NaCl or KCl 0.30 (2 ) 2.1 (0.13) NaNO 3 0.60 (5) 2.1 (0.13) Steel; hardened tool steel NaClO 3 0.78 (6 ) 2.0 (0.12) Gray iron NaCl 0.30 (2 ) 2.0 (0.12) (a) (b) NaNO 3 0.60 (5) 2.0 (0.12) (a) (b) White cast iron NaNO 3 0.60 (5) 1.6 (0.10) (c) Aluminum and aluminum alloys (d) NaNO 3 0.60...

23

Electrolytes  

Science Conference Proceedings (OSTI)

Table 3   Electrolytes for the electrochemical machining of metals...cobalt-base alloys NaCl or KCl 0.30 2.5 2.1 0.13 NaNO 3 0.60 5 2.1 0.13 Steel; hardened tool steel NaClO 3 0.78 6.5 2.0 0.12 Gray iron NaCl 0.30 2.5 2.0 (a) (b) 0.12 (a) (b) NaNO 3 0.60 5 2.0 (a) (b) 0.12 (a) (b) White cast iron NaNO 3 0.60 5 1.6 (c) 0.10 (c) Aluminum and aluminum

24

Modeling of polymer electrolyte fuel cell systems  

DOE Green Energy (OSTI)

Propulsion systems based on the polymer electrolyte fuel cell (PEFC) are being developed. This paper reports an analysis undertaken to design improved PEFC systems. A reference system design with some variants were set up for a methanol-fueled PEFC propulsion system. Efficiency improves from 38.4 to 44.1% as cell current density goes from 0.75 to 0.45 A/cm{sup 2}, while fuel cell efficiency increases from 52.6 to 60.0%; to get a net power output of 80 kWe, the active fuel cell area must increase from 18.8 to 27.3 m{sup 2}. Three parametric studies were conducted on the off-design performance of the reference system.

Kumar, R.; Ahluwalia, R.; Geyer, H.K.; Krumpelt, M.

1993-09-01T23:59:59.000Z

25

A Pentafluorophenylboron Oxalate Additive in Non-aqueous Electrolytes 3 for Lithium Batteries  

DOE Green Energy (OSTI)

A novel compound named pentafluorophenylboron oxalate (PFPBO) has been synthesized. PFPBO has a unique molecular structure containing a boron atom center with electron deficiency and an oxalate group. It is found that when PFPBO is used as additive, the solubility of lithium fluoride (LiF) or lithium oxide (Li{sub 2}O, Li{sub 2}O{sub 2}) in propylene carbonate (PC) and dimethyl carbonate (DMC) solvents can be increased dramatically. The new electrolytes show high ionic conductivity, high lithium ion transference number and good compatibility with LiMn{sub 2}O{sub 4} cathode and MCMB anode. PFPBO was synthesized with the designed structure to act as a bi-functional additive: boron-based anion receptor (BBAR) additive and stable solid electrolyte interphase (SEI) formation additive in PC-based electrolytes. The results show it does possess these two desired functionalities.

Yang, X.Q.; Li, L.F.; Lee, H.S.; Li, H.; Huang, X.J.

2009-12-01T23:59:59.000Z

26

Development of an Experimental Data Base and Theories for Prediction of Thermodynamic Properties of Aqueous Electrolytes and Nonelectrolytes of Geochemical Significance at Supercritical Temperatures and Pressures.  

DOE Green Energy (OSTI)

The objective of this research was to combine new experimental measurements on heat capacities, volumes, and association constants of key compounds with theoretical equations of state and with first principles quantum mechanical calculations to generate predictions of thermodynamic data. The resulting thermodynamic data allow quantitative models of geochemical processes at high temperatures and pressures. Research funded by a DOE grant to Prof. Robert Wood at the University of Delaware involved the development of new theoretical equations of state for aqueous solutions of electrolytes and non-electrolytes, methods to estimate thermodynamic data not available from experiments, collection of data on model compounds through experiments and predictions of properties using ab initio quantum mechanics. During the last three and a half years, with support from our DOE grant, 16 papers have been accepted or published, and 3 more are in preparation. Results of this research have been reported in numerous invited and contributed presentations at national and international meetings. For this report, we will briefly comment on the highlights of the last 3 and a half years and give a complete list of papers published, accepted, or submitted during these years.

Wood, Robert H.

2005-10-11T23:59:59.000Z

27

H+ diffusion and electrochemical stability of Li1+x+yAlxTi2-xSiyP3-yO12 glass in aqueous Li/air battery electrolytes  

SciTech Connect

It is well known that LATP (Li1+x+y AlxTi2?x SiyP3?yO12) glass is a good lithium ion conductor. However, the interaction between LATP glass and H+ ions (including its diffusion and surface adsorption) needs to be well understood before the long-term application of LATP glass in an aqueous electrolyte based Li-air batteries where H+ always present. In this work, we investigate the H+ ion diffusion properties in LATP glass and their surface interactions using both experimental and modeling approaches. Our analysis indicates that the apparent H+ related current observed in the initial cyclic voltammetry scan should be attributed to the adsorption of H+ ions on the LATP glass rather than the bulk diffusion of H+ ions in the glass. Furthermore, the density functional theory calculations indicate that the H+ ion diffusion energy barrier (3.21 eV) is much higher than that of Li+ ion (0.79 eV) and Na+ ion (0.79 eV) in NASICON type LiTi2(PO4)3 material. As a result, the H+ ion conductivity in LATP glass is negligible at room temperature. However, significant surface corrosion was found after the LATP glass was soaked in strong alkaline electrolyte for extended time. Therefore, appropriate electrolytes have to be developed to prevent the corrosion of LATP glass before its practical application for Li-air batteries using aqueous electrolyte.

Ding, Fei; Xu, Wu; Shao, Yuyan; Chen, Xilin; Wang, Zhiguo; Gao, Fei; Liu, Xingjiang; Zhang, Jiguang

2012-09-15T23:59:59.000Z

28

A Universal Model for Nanoporous Carbon Supercapacitors Applicable to Diverse Pore Regimes, Carbons, and Electrolyte  

SciTech Connect

Supercapacitors, commonly called electric double-layer capacitors (EDLCs), are emerging as a novel type of energy storage device with the potential to substitute batteries in applications requiring high power densities. In response to the latest experimental breakthrough in nanoporous carbon supercapacitors, we propose a heuristic theoretical model that takes pore curvature into account as a replacement for the EDLC model which is based on a traditional parallel-plate capacitor. When the pore size is in the mesopore regime (2-50 nm), counterions enter mesoporous carbons and approach the pore wall to form an electric double-cylinder capacitor (EDCC); in the micropore regime (< 2 nm), solvated/desolvated counterions line up along the pore axis to form an electric wire-in-cylinder capacitor (EWCC). In the macropore regime (> 50 nm) where pores are large enough so that the pore curvature is no longer significant, the EDCC model can be reduced naturally to the EDLC model. We present density functional theory calculations and detailed analyses of available experimental data in various pore regimes, showing the significant effects of pore curvature on the supercapacitor properties of nanoporous carbons. It is shown that the EDCC/EWCC model is universal to carbon supercapacitors with diverse carbon materials including activated carbons, template carbons, and novel carbide-derived carbons, and with diverse electrolytes including organic electrolytes such as tetraethylammonium tetrafluoroborate (TEABF4), tetraethylammonium methyl-sulfonate (TEAMS) in acetonitrile, aqueous H2SO4 and KOH electrolytes, and even ionic liquid electrolyte such as 1-ethyl-3-methylimmidazolium bis(trifluromethane-sulfonyl)imide (EMI-TFSI). The EDCC/EWCC model allows the supercapacitor properties to be correlated with pore size, specific surface area, Debye length, electrolyte concentration and dielectric constant, and solute ion size, and may lend a support for the systematic optimization of the properties of carbon supercapacitors via experiments. On the basis of the insight obtained from the new model, we also discuss the effects of the kinetic solvation/desolvation process, multimodal (versus unimodal) pore size distribution, and exohedral (versus endohedral) capacitors on the electrochemical properties of supercapacitors.

Sumpter, Bobby G [ORNL; Huang, Jingsong [ORNL; Meunier, Vincent [ORNL

2008-01-01T23:59:59.000Z

29

Vapor pressure measurements on non-aqueous electrolyte solutions. Part 2. Tetraalkylammonium salts in methanol. Activity coefficients of various 1-1 electrolytes at high concentrations  

SciTech Connect

Precise vapor pressure data for solutions of Et/sub 4/NBr, Bu/sub 4/NBr, Bu/sub 4/Nl, Bu/sub 4/NClO/sub 4/, and Am/sub 4/NBr in methanol at 25/sup 0/C in the concentration range 0.04 < m(mol-(kg of solvent)/sup -1/) < 1.6 are communicated and discussed. Polynomials in molalities are given which may be used for calculating precise vapor pressure depressions of these solutions. Osmotic coefficients are calculated by taking into account the second virial coefficient of methanol vapor. Discussion of the data at low concentrations is based on the chemical model of electrolyte solutions taking into account non-coulombic interactions; ion-pair association constants are compared to those of conductance measurements. Pitzer equations are used to reproduce osmotic and activity coefficient at high concentrations; the set of Pitzer parameters b = 3.2, ..cap alpha../sub 1/ = 2.0 and ..cap alpha../sub 2/ = 20.0 is proposed for methanol solutions.

Barthel, J.; Lauermann, G.; Neueder, R.

1986-10-01T23:59:59.000Z

30

A Thermal Model to Evaluate Sub-Freezing Startup for a Direct Hydrogen Hybrid Fuel Cell Vehicle Polymer Electrolyte Fuel Cell Stack and System  

E-Print Network (OSTI)

V Solid Polymer Electrolyte Fuel Cell, I. Mechanistic ModelI V Solid Polymer Electrolyte Fuel Cell, II. Empirical Modelexchange membrane fuel cells," Journal of Power Sources,

Sundaresan, Meena

2004-01-01T23:59:59.000Z

31

A Thermal Model to Evaluate Sub-Freezing Startup for a Direct Hydrogen Hybrid Fuel Cell Vehicle Polymer Electrolyte Fuel Cell Stack and System  

E-Print Network (OSTI)

IV Solid Polymer Electrolyte Fuel Cell, I. Mechanistic ModelIV Solid Polymer Electrolyte Fuel Cell, II. Empirical Modelexchange membrane fuel cells," Journal of Power Sources,

Sundaresan, Meena

2004-01-01T23:59:59.000Z

32

Ceramic electrolyte coating and methods  

SciTech Connect

Aqueous coating slurries useful in depositing a dense coating of a ceramic electrolyte material (e.g., yttrium-stabilized zirconia) onto a porous substrate of a ceramic electrode material (e.g., lanthanum strontium manganite or nickel/zirconia) and processes for preparing an aqueous suspension of a ceramic electrolyte material and an aqueous spray coating slurry including a ceramic electrolyte material. The invention also includes processes for depositing an aqueous spray coating slurry including a ceramic electrolyte material onto pre-sintered, partially sintered, and unsintered ceramic substrates and products made by this process.

Seabaugh, Matthew M. (Columbus, OH); Swartz, Scott L. (Columbus, OH); Dawson, William J. (Dublin, OH); McCormick, Buddy E. (Dublin, OH)

2007-08-28T23:59:59.000Z

33

Compatibility of Lithium Salts with Solvent of the Non-Aqueous Electrolyte in Li–O2 Batteries  

SciTech Connect

The stability of lithium salts, especially in the presence of reduced oxygen species, O2 and H2O (even in a small amount), plays an important role in the cyclability and capacity of Li–O2 cells. This combined experimental and computational study provides evidence that the stability of the electrolyte used in Li–O2 cells strongly depends on the compatibility of lithium salts with solvent. In the case of the LiPF6–1NM3 electrolyte, the decomposition of LiPF6 occurs in the cell as evidenced by in situ XRD, FT-IR and XPS analysis, which triggers the decomposition of 1NM3 solvent due to formation of HF from the decomposition of LiPF6. These reactions lead to degradation of the electrolyte and cause poor cyclability of the cell. The same reactions are not observed when LiTFSI and LiCF3SO3 are used as the lithium salts in 1NM3 solvent, or LiPF6 is used in TEGDME solvent.

Du, Peng; Lu, Jun; Lau, Kah Chun; Luo, Xiangyi; Bareno, Javier; Zhang, Xiaoyi; Ren, Yang; Zhang, Zhengcheng; Curtiss, Larry A.; Sun, Yang-Kook; Amine, Khalil

2013-02-20T23:59:59.000Z

34

Synthesis and studies of boron based anion receptors and their use in non-aqueous electrolytes for lithium batteries  

DOE Green Energy (OSTI)

A new family of anion receptors based on boron compounds has been synthesized. These compounds can be used as anion receptors in lithium battery electrolytes and can greatly increase solubility and ionic conductivities of various lithium salts, such as LiF, LiCl, CF{sub 3}COOLi and C{sub 2}F{sub 5}COOLi, in DME solutions. Near Edge X-ray Absorption Fine Structure (NEXAFS) spectroscopy studies show that Cl{sup {minus}} anions of LiCl are complexed with these compounds in DME solutions. The electrochemical stability of lithium salts and one of the boron compounds in deferent solvents was studied. For the first time, LiF has been successfully used as conducting salt in a novel electrolyte with this boron compound as an additive in DME. A rechargeable Li/LiMn{sub 2}O{sub 4} cell using this electrolyte was successfully cycled 51 times. However, the capacity fades with cycling due to decomposition of the solvent. The cycling performance of the battery was greatly improved by replacing DME with PC-EC-DMC as the solvent.

Sun, X.; Yang, X.Q.; Lee, H.S.; McBreen, J. [Brookhaven National Lab., Upton, NY (United States); Choi, L.S. [Naval Research Lab., Washington, DC (United States)

1998-12-31T23:59:59.000Z

35

Fe sub 3 Al-type iron aluminides: Aqueous corrosion properties in a range of electrolytes and slow-strain-rate ductilities during aqueous corrosion  

DOE Green Energy (OSTI)

The Fe{sub 3}Al-type iron aluminides have undergone continued development at the Oak Ridge National Laboratory for enhancement of mechanical and corrosion properties. Improved alloys and thermomechanical processing methods have evolved. The overall purpose of the project herein described was to evaluate the aqueous corrosion properties of the most recent alloy compositions in a wide range of possibly-aggressive solutions and under several different types of corrosion-test conditions. The work supplements previous aqueous-corrosion studies on iron aluminides by the present authors. Four stages of this one-year aqueous-corrosion investigation are described. First the corrosion properties of selected iron aluminides were evaluated by means of electrochemical tests and longer-time immersion tests in a range of acidic, basic and chloride solutions. Theses tests were performed under non-crevice conditions, i.e. the specimens were not designed to contain crevice geometries. Second, the iron-aluminide alloy that proved most resistance to chloride-induced localized corrosion under non-crevice conditions was further evaluated under more-severe crevice conditions by electrochemical and immersion testing. Third, in order to study the relative roles of Fe, Al, Cr and Mo in the formation of passive films, the chemical compositions of passive films were determined by X-ray photoelectron spectroscopy (XPS). And fourth, in order to study aqueous-corrosion effects on the ductilities of iron aluminides as related to hydrogen embrittlement and/or stress-corrosion cracking, slow-strain-rate corrosion (SSRC) tests were conducted over a range of electrochemical potentials.

Buchanan, R.A.; Kim, J.G. (Tennessee Univ., Knoxville, TN (United States). Dept. of Materials Science and Engineering)

1992-08-01T23:59:59.000Z

36

Fe{sub 3}Al-type iron aluminides: Aqueous corrosion properties in a range of electrolytes and slow-strain-rate ductilities during aqueous corrosion  

DOE Green Energy (OSTI)

The Fe{sub 3}Al-type iron aluminides have undergone continued development at the Oak Ridge National Laboratory for enhancement of mechanical and corrosion properties. Improved alloys and thermomechanical processing methods have evolved. The overall purpose of the project herein described was to evaluate the aqueous corrosion properties of the most recent alloy compositions in a wide range of possibly-aggressive solutions and under several different types of corrosion-test conditions. The work supplements previous aqueous-corrosion studies on iron aluminides by the present authors. Four stages of this one-year aqueous-corrosion investigation are described. First the corrosion properties of selected iron aluminides were evaluated by means of electrochemical tests and longer-time immersion tests in a range of acidic, basic and chloride solutions. Theses tests were performed under non-crevice conditions, i.e. the specimens were not designed to contain crevice geometries. Second, the iron-aluminide alloy that proved most resistance to chloride-induced localized corrosion under non-crevice conditions was further evaluated under more-severe crevice conditions by electrochemical and immersion testing. Third, in order to study the relative roles of Fe, Al, Cr and Mo in the formation of passive films, the chemical compositions of passive films were determined by X-ray photoelectron spectroscopy (XPS). And fourth, in order to study aqueous-corrosion effects on the ductilities of iron aluminides as related to hydrogen embrittlement and/or stress-corrosion cracking, slow-strain-rate corrosion (SSRC) tests were conducted over a range of electrochemical potentials.

Buchanan, R.A.; Kim, J.G. [Tennessee Univ., Knoxville, TN (United States). Dept. of Materials Science and Engineering

1992-08-01T23:59:59.000Z

37

Modeling Water Management in Polymer-Electrolyte Fuel Cells  

E-Print Network (OSTI)

membrane, liquid and ice phases; the movement of ice throughthe membrane, vapor, and ice phases. As in their 1-D model,species, element index, or ice phase = into the control

Weber, Adam; Department of Chemical Engineering, University of California, Berkeley

2008-01-01T23:59:59.000Z

38

Modeling aerosol growth by aqueous chemistry in nonprecipitating stratiform cloud  

SciTech Connect

A new microphysics module based on a two-dimensional (2D) joint size distribution function representing both interstitial and cloud particles is developed and applied to studying aerosol processing in non-precipitating stratocumulus clouds. The module is implemented in a three-dimensional dynamical framework of a large-eddy simulation (LES) model and in a trajectory ensemble model (TEM). Both models are used to study the modification of sulfate aerosol by the activation - aqueous chemistry - resuspension cycle in shallow marine stratocumulus clouds. The effect of particle mixing and different size-distribution representations on modeled aerosol processing are studied in a comparison of the LES and TEM simulations with the identical microphysics treatment exposes and a comparison of TEM simulations with a 2D fixed and moving bin microphysics. Particle mixing which is represented in LES and neglected in the TEM leads to the mean relative per particle dry mass change in the TEM simulations being about 30% lower than in analogous subsample of LES domain. Particles in the final LES spectrum are mixed in from different “parcels”, some of which have experienced longer in-cloud residence times than the TEM parcels, all of which originated in the subcloud layer, have. The mean relative per particle dry mass change differs by 14% between TEM simulations with fixed and moving bin microphysics. Finally, the TEM model with the moving bin microphysics is used to evaluate assumptions about liquid water mass partitioning among activated cloud condensation nuclei (CCN) of different dry sizes. These assumptions are used in large-scale models to map the bulk aqueous chemistry sulfate production, which is largely proportional to the liquid water mass, to the changes in aerosol size distribution. It is shown that the commonly used assumptions that the droplet mass is independent of CCN size or that the droplet mass is proportional to the CCN size to the third power do not perform well in the considered case. The explicitly predicted water partitioning indicates that the mean mass of droplets participating in the models aqueous chemistry calculations is proportional to the dry CCN size.

Ovchinnikov, Mikhail; Easter, Richard C.

2010-07-29T23:59:59.000Z

39

Integrated photovoltaic electrolytic cell  

SciTech Connect

A photovoltaic-electrolytic unit is provided to produce an electric current from solar energy and utilize the current to produce hydrogen by the electrolysis of water. The unit floats in an aqueous medium so that photoelectric cells are exposed to solar radiation, and electrodes submerged in the medium produce oxygen which is vented and hydrogen which is collected in the unit.

Ohkawa, T.

1982-10-05T23:59:59.000Z

40

Modeling the Electrochemistry of an SOFC through the Electrodes and Electrolyte  

Science Conference Proceedings (OSTI)

This paper describes a distributed electrochemistry model of the solid oxide fuel cell (SOFC) electrodes and electrolyte. The distributed electrochemistry (DEC) model solves the transport, reactions, and electric potential through the thickness of the SOFC electrodes. The DEC model allows the local conditions within the electrodes to be studied and allows for a better understanding of how electrochemical and microstructural parameters affect the electrodes. In this paper the governing equations and implementation of the DEC model are presented along with several case studies which are used to investigate the sensitivity of the cathode to the microstructural and electrochemical parameters of the model and to explore methods of improving the electrochemical performance of the SOFC cathode.

Ryan, Emily M.; Recknagle, Kurtis P.; Khaleel, Mohammad A.

2011-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "aqueous electrolyte modeling" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Using a Quasipotential Transformation for Modeling Diffusion Media inPolymer-Electrolyte Fuel Cells  

SciTech Connect

In this paper, a quasipotential approach along with conformal mapping is used to model the diffusion media of a polymer-electrolyte fuel cell. This method provides a series solution that is grid independent and only requires integration along a single boundary to solve the problem. The approach accounts for nonisothermal phenomena, two-phase flow, correct placement of the electronic potential boundary condition, and multilayer media. The method is applied to a cathode diffusion medium to explore the interplay between water and thermal management and performance, the impact of the rib-to-channel ratio, and the existence of diffusion under the rib and flooding phenomena.

Weber, Adam Z.; Newman, John

2008-08-29T23:59:59.000Z

42

A thermodynamic model for aqueous solutions of liquid-like density  

DOE Green Energy (OSTI)

The paper describes a model for the prediction of the thermodynamic properties of multicomponent aqueous solutions and discusses its applications. The model was initially developed for solutions near room temperature, but has been found to be applicable to aqueous systems up to 300/sup 0/C or slightly higher. A liquid-like density and relatively small compressibility are assumed. A typical application is the prediction of the equilibrium between an aqueous phase (brine) and one or more solid phases (minerals). (ACR)

Pitzer, K.S.

1987-06-01T23:59:59.000Z

43

Using a Quasipotential Transformation for Modeling Diffusion Media in Polymer-Electrolyte Fuel Cells  

E-Print Network (OSTI)

Proton Exchange Membrane Fuel Cell , Numerical Heat Transferof Polymer Electrolyte Fuel Cells Using a Two-EquationExchange Membrane Fuel Cells 2. Absolute Permeability ,

Weber, Adam Z.

2008-01-01T23:59:59.000Z

44

Boron compounds as anion binding agents for nonaqueous battery electrolytes  

DOE Patents (OSTI)

Novel fluorinated boron-based compounds which act as anion receptors in non-aqueous battery electrolytes are provided. When added to non-aqueous battery electrolytes, the fluorinated boron-based compounds of the invention enhance ionic conductivity and cation transference number of non-aqueous electrolytes. The fluorinated boron-based anion receptors include borane and borate compounds bearing different fluorinated alkyl and aryl groups.

Lee, Hung Sui (East Setauket, NY); Yang, Xia-Oing (Port Jefferson Station, NY); McBreen, James (Bellport, NY); Xiang, Caili (Upton, NY)

2000-02-08T23:59:59.000Z

45

Aerosol–Cloud Interactions in a Mesoscale Model. Part II: Sensitivity to Aqueous-Phase Chemistry  

Science Conference Proceedings (OSTI)

The feedbacks between aerosols, cloud microphysics, and cloud chemistry are investigated in a mesoscale model. A simple bulk aqueous-phase sulfur chemistry scheme was fully coupled to the existing aerosol and microphysics schemes. The ...

Irena T. Ivanova; Henry G. Leighton

2008-02-01T23:59:59.000Z

46

Electrolytic dissolver  

DOE Patents (OSTI)

This patent related to an electrolytic dissolver wherein dissolution occurs by solution contact including a vessel of electrically insulative material, a fixed first electrode, a movable second electrode, means for insulating the electrodes from the material to be dissolved while permitting a free flow of electrolyte therebetween, means for passing a direct current between the electrodes and means for circulating electrolyte through the dissolver. (auth)

Wheelwright, E.J.; Fox, R.D.

1975-08-26T23:59:59.000Z

47

Book Review of Electrolytes...  

Science Conference Proceedings (OSTI)

Book Review of Electrolytes. Properties of Solutions. ... We review the book entitled, "Electrolytes. Properties of Solutions. ...

48

Ion Partitioning at the liquid/vapor interface of a multi-component alkali halide solution: A model for aqueous sea salt aerosols  

E-Print Network (OSTI)

model for aqueous sea salt aerosols Sutapa Ghosal, 1 Matthewwith sea salt ice and aerosols has been implicated in theof aqueous sea salt aerosols and particles have been

Ghosal, Sutapa

2009-01-01T23:59:59.000Z

49

Smoothed particle hydrodynamics model of non-aqueous phase liquid flow and dissolution  

Science Conference Proceedings (OSTI)

A smoothed particle hydrodynamics model was developed to simulate the flow of mixtures of aqueous and non-aqueous phase liquids in porous media and the dissolution of the non-aqueous phase in the aqueous phase. The model was used to study the effects of pore-scale heterogeneity and anisotropy on the steady state dense non-aqueous phase liquid (DNAPL) saturation when gravity driven DNAPL displaces water from initially water saturated porous media. Pore-scale anisotropy was created by using co-oriented non overlapping elliptically shaped grains to represent the porous media. After a steady state DNAPL saturation was reached, water was injected until a new steady state DNAPL saturation was reached. The amount of trapped DNAPL was found to be greater when DNAPL is displaced in the direction of the major axes of the soil grains than when it is displaced in the direction of the minor axes of the soil grains. The amount of trapped DNAPL was also found to increase with decreasing initial saturation of the continuous DNAPL phase. For the conditions used in our simulations, the saturation of the trapped NAPL with a smaller initial DNAPL saturation was more than 3 times larger than the amount of trapped DNAPL with a larger initial saturation. These simulations were carried out assuming that the DNAPL did not dissolve in water. Simulations including the effect of dissolution of DNAPL in the aqueous phase were also performed, and effective (macroscopic) mass transfer coefficients were determined.

Tartakovsky, Alexandre M.; Meakin, Paul; Ward, Anderson L.

2009-01-01T23:59:59.000Z

50

Modeling the Removal of Uranium U(VI) from Aqueous Solutions in the  

E-Print Network (OSTI)

Modeling the Removal of Uranium U(VI) from Aqueous Solutions in the Presence of Sulfate Reducing Colorado School of Mines, Division of Environmental Science and Engineering, Golden, Colorado 80401 The reduction kinetics of soluble hexavalent uranium (U(VI)) to insoluble tetravalent U(IV) by both a mixed

51

Effective Diffusion-Medium Thickness for Simplified Polymer-Electrolyte-Fuel-Cell Modeling  

SciTech Connect

In this manuscript, conformal mapping is applied to a rib/channel domain of a polymer-electrolyte-fuel-cell diffusion medium. The analysis leads to the calculation of an effective diffusion-medium thickness, which can subsequently be used in 1-D simulations to account for the average rib/channel 2-D geometric effect. Extensions of the analysis to anisotropic and multilayer diffusion media are also given. Both equations and figures show the impact on a given variable at the catalyst layer of having a combined conducting/nonconducting boundary across from it.

Weber, Adam; Weber, Adam Z.

2008-07-30T23:59:59.000Z

52

ELECTROLYTIC PRODUCTION OF URANIUM TETRAFLUORIDE  

DOE Patents (OSTI)

This patent relates to electrolytic methods for the production of uranium tetrafluoride. According to the present invention a process for the production of uranium tetrafluoride comprises submitting to electrolysis an aqueous solution of uranyl fluoride containing free hydrofluoric acid. Advantageously the aqueous solution of uranyl fluoride is obtained by dissolving uranium hexafluoride in water. On electrolysis, the uranyl ions are reduced to uranous tons at the cathode and immediately combine with the fluoride ions in solution to form the insoluble uranium tetrafluoride which is precipitated.

Lofthouse, E.

1954-08-31T23:59:59.000Z

53

Modeling of aqueous and organic phase speciation for solvent extraction systems  

SciTech Connect

The TRUEX (TRansUranic EXtraction) solvent extraction process has the ability to remove, separate, and recover transuranic (TRU) elements from acidic nuclear waste solutions. A computer model of the TRUEX process is currently being developed for use in flowsheet design and process optimization. The correlations that are to be used in the model for generating extraction distribution ratios are based on chemical mass action principles and require calculation of aqueous and organic phase speciation. Aqueous phase activity coefficients are calculated using methods available in the literature, while the organic phase species are treated in terms of ideal associated solution theory. This approach is demonstrated for the extraction of HNO/sub 3/, HTcO/sub 4/, and americium nitrate by n-octyl(phenyl)-N,N-diisobutylcarbamoyl-methylphosphine oxide (CMPO)---the primary metal extractant in the TRUEX solvent. 23 refs., 5 figs.

Chaiko, D.J.; Tse, Pui-Kwan; Vandegrift, G.F

1988-11-01T23:59:59.000Z

54

Electrolytic orthoborate salts for lithium batteries  

DOE Patents (OSTI)

Orthoborate salts suitable for use as electrolytes in lithium batteries and methods for making the electrolyte salts are provided. The electrolytic salts have one of the formulae (I). In this formula anionic orthoborate groups are capped with two bidentate chelating groups, Y1 and Y2. Certain preferred chelating groups are dibasic acid residues, most preferably oxalyl, malonyl and succinyl, disulfonic acid residues, sulfoacetic acid residues and halo-substituted alkylenes. The salts are soluble in non-aqueous solvents and polymeric gels and are useful components of lithium batteries in electrochemical devices.

Angell, Charles Austen (Mesa, AZ); Xu, Wu (Tempe, AZ)

2008-01-01T23:59:59.000Z

55

Quasi-steady model for predicting temperature of aqueous foams circulating in geothermal wellbores  

DOE Green Energy (OSTI)

A quasi-steady model has been developed for predicting the temperature profiles of aqueous foams circulating in geothermal wellbores. The model assumes steady one-dimensional incompressible flow in the wellbore; heat transfer by conduction from the geologic formation to the foam is one-dimensional radially and time-dependent. The vertical temperature distribution in the undisturbed geologic formation is assumed to be composed of two linear segments. For constant values of the convective heat-transfer coefficient, a closed-form analytical solution is obtained. It is demonstrated that the Prandtl number of aqueous foams is large (1000 to 5000); hence, a fully developed temperature profile may not exist for representative drilling applications. Existing convective heat-transfer-coefficient solutions are adapted to aqueous foams. The simplified quasi-steady model is successfully compared with a more-sophisticated finite-difference computer code. Sample temperature-profile calculations are presented for representative values of the primary parameters. For a 5000-ft wellbore with a bottom hole temperature of 375{sup 0}F, the maximum foam temperature can be as high as 300{sup 0}F.

Blackwell, B.F.; Ortega, A.

1983-01-01T23:59:59.000Z

56

Electrolyte salts for nonaqueous electrolytes  

Science Conference Proceedings (OSTI)

Metal complex salts may be used in lithium ion batteries. Such metal complex salts not only perform as an electrolyte salt in a lithium ion batteries with high solubility and conductivity, but also can act as redox shuttles that provide overcharge protection of individual cells in a battery pack and/or as electrolyte additives to provide other mechanisms to provide overcharge protection to lithium ion batteries. The metal complex salts have at least one aromatic ring. The aromatic moiety may be reversibly oxidized/reduced at a potential slightly higher than the working potential of the positive electrode in the lithium ion battery. The metal complex salts may also be known as overcharge protection salts.

Amine, Khalil; Zhang, Zhengcheng; Chen, Zonghai

2012-10-09T23:59:59.000Z

57

Pore-Scale Modeling of Two-Phase Transport in Polymer Electrolyte Fuel Cells - Progress and Perspective  

Science Conference Proceedings (OSTI)

Recent years have witnessed an explosion of research and development efforts in the area of polymer electrolyte fuel cells (PEFC), perceived as the next generation clean energy source for automotive, portable and stationary applications. Despite significant progress, a pivotal performance/durability limitation in PEFCs centers on two-phase transport and mass transport loss originating from suboptimal liquid water transport and flooding phenomena. Liquid water blocks the porous pathways in the gas diffusion layer (GDL) and the catalyst layer (CL), thus hindering oxygen transport from the flow field to the electrochemically actives sites in the catalyst layer. Different approaches have been examined to model the underlying transport mechanisms in the PEFC with different levels of complexities. Due to the macroscopic nature, these two-phase models fail to resolve the underlying structural influence on the transport and performance. Mesoscopic modeling at the pore-scale offers great promise in elucidating the underlying structure-transport-performance interlinks in the PEFC porous components. In this article, a systematic review of the recent progress and prospects of pore-scale modeling in the context of two-phase transport in the PEFC is presented. Specifically, the efficacy of lattice Boltzmann (LB), pore morphology (PM) and pore network (PN) models coupled with realistic delineation of microstructures in fostering enhanced insight into the underlying liquid water transport in the PEFC GDL and CL is highlighted.

Mukherjee, Partha P [ORNL

2010-01-01T23:59:59.000Z

58

Pseudo-capacitor device for aqueous electrolytes  

DOE Patents (OSTI)

A pseudo-capacitor having a high energy storage capacity develops a double layer capacitance as well as a Faradaic or battery-like redox reaction, also referred to as pseudo-capacitance. The Faradaic reaction gives rise to a capacitance much greater than that of the typical ruthenate oxide ultracapacitor which develops only charge separation-based double layer capacitance. The capacitor employs a lead and/or bismuth/ruthenate and/or iridium system having the formula A.sub.2 ›B.sub.2-x Pb.sub.x !O.sub.7-y, where A=Pb, Bi, and B=Ru, Ir, and O

Prakash, Jai (3849 NW. 65th Ave., Gainesville, FL 32653); Thackeray, Michael M. (1763 Cliffside Ct., Naperville, IL 60565); Dees, Dennis W. (6224 Middaugh Ave., Downers Grove, IL 60516); Vissers, Donald R. (611 Clover Ct., Naperville, IL 60540); Myles, Kevin M. (1231 60th Pl., Downers Grove, IL 60516-1856)

1998-01-01T23:59:59.000Z

59

Pseudo-capacitor device for aqueous electrolytes  

DOE Patents (OSTI)

A pseudo-capacitor having a high energy storage capacity develops a double layer capacitance as well as a Faradaic or battery-like redox reaction, also referred to as pseudo-capacitance. The Faradaic reaction gives rise to a capacitance much greater than that of the typical ruthenate oxide ultracapacitor which develops only charge separation-based double layer capacitance. The capacitor employs a lead and/or bismuth/ruthenate and/or iridium system having the formula A{sub 2}[B{sub 2{minus}x}Pb{sub x}]O{sub 7{minus}y}, where A=Pb, Bi, and B=Ru, Ir, and O

Prakash, J.; Thackeray, M.M.; Dees, D.W.; Vissers, D.R.; Myles, K.M.

1998-11-24T23:59:59.000Z

60

Cathode for the electrolytic production of hydrogen  

SciTech Connect

The invention relates to a cathode for the electrolytic production of hydrogen. The cathode comprises an active surface consisting of a metal oxide obtained by the thermal decomposition of a thermally decomposable compound of a metal chosen from amongst cobalt, iron, manganese or nickel. The cathode is particularly suitable for the electrolysis of aqueous sodium chloride solutions in cells with a permeable diaphragm.

Nicolas, E.

1983-07-19T23:59:59.000Z

Note: This page contains sample records for the topic "aqueous electrolyte modeling" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

HANFORD RIVER PROTECTION PROJECT ENHANCED MISSION PLANNING THROUGH INNOVATIVE TOOLS LIFECYCLE COST MODELING AND AQUEOUS THERMODYNAMIC MODELING - 12134  

SciTech Connect

Two notable modeling efforts within the Hanford Tank Waste Operations Simulator (HTWOS) are currently underway to (1) increase the robustness of the underlying chemistry approximations through the development and implementation of an aqueous thermodynamic model, and (2) add enhanced planning capabilities to the HTWOS model through development and incorporation of the lifecycle cost model (LCM). Since even seemingly small changes in apparent waste composition or treatment parameters can result in large changes in quantities of high-level waste (HLW) and low-activity waste (LAW) glass, mission duration or lifecycle cost, a solubility model that more accurately depicts the phases and concentrations of constituents in tank waste is required. The LCM enables evaluation of the interactions of proposed changes on lifecycle mission costs, which is critical for decision makers.

PIERSON KL; MEINERT FL

2012-01-26T23:59:59.000Z

62

Modeling of concentrated aqueous solutions: Efficient implementation of Pitzer equations in geochemical and reactive transport models  

Science Conference Proceedings (OSTI)

Modeling concentrated solutions demands the use of ion-interaction models such as Pitzer equations, which involve a large number of operations. Implementation of these models in large reactive transport simulations significantly increases the computation ... Keywords: Concentrated solutions, Evaporation of seawater, Geochemical modeling, HMW model, Invariant points, Object-oriented programming, Pitzer, Reactive transport modeling

S. A. Bea; J. Carrera; C. Ayora; F. Batlle

2010-04-01T23:59:59.000Z

63

Molten salt electrolyte separator  

DOE Patents (OSTI)

A molten salt electrolyte/separator for battery and related electrochemical systems including a molten electrolyte composition and an electrically insulating solid salt dispersed therein, to provide improved performance at higher current densities and alternate designs through ease of fabrication.

Kaun, Thomas D. (New Lenox, IL)

1996-01-01T23:59:59.000Z

64

Electrolytic production of hydrogen. [from carbonaceous materials  

SciTech Connect

A cyclic electrolytic process is claimed for the manufacture of hydrogen from carbonaceous material such as coal, agricultural wastes and garbage to produce commercial hydrogen. An alakli metal sulfate is reduced to an alkali metal sulfide by reaction of the sulfate and carbonaceous fuel at an elevated temperature. The sulfide and impurities derived from the fuel are digested with an aqueous solution to dissolve the sulfide and separate out the impurities. The solution of the alkali sulfide is added to electrolytic cells in which an electric current is utilized to generate hydrogen at the cathode while oxidizing the sulfide substantially to sulfate at the anode. The cell electrolyte temperature is greater than 150/sup 0/C and less than 350/sup 0/C. Under these conditions the polarization problem encountered in hydrogen/oxygen cells is substantially avoided. The alkali sulfate is then separated from the electrolyte stream exiting from the electrolytic cells, reduced again by burning with fuel and recycled to the electrolytic cell.

Spitzer, R.

1978-03-28T23:59:59.000Z

65

Lithium ion conducting electrolytes  

DOE Patents (OSTI)

The present invention relates generally to highly conductive alkali-metal ion non-crystalline electrolyte systems, and more particularly to novel and unique molten (liquid), rubbery, and solid electrolyte systems which are especially well suited for use with high current density electrolytic cells such as primary and secondary batteries.

Angell, Charles Austen (Mesa, AZ); Liu, Changle (Midland, MI); Xu, Kang (Montgomery Village, MD); Skotheim, Terje A. (Tucson, AZ)

1999-01-01T23:59:59.000Z

66

Solid polymer electrolyte compositions  

DOE Patents (OSTI)

An electrolyte composition is featured that includes a solid, ionically conductive polymer, organically modified oxide particles that include organic groups covalently bonded to the oxide particles, and an alkali metal salt. The electrolyte composition is free of lithiated zeolite. The invention also features cells that incorporate the electrolyte composition.

Garbe, James E. (Stillwater, MN); Atanasoski, Radoslav (Edina, MN); Hamrock, Steven J. (St. Paul, MN); Le, Dinh Ba (St. Paul, MN)

2001-01-01T23:59:59.000Z

67

Novel Nonflammable Electrolytes for Secondary Magnesium Batteries and High Voltage Electrolytes for Electrochemcial Supercapacitors  

Science Conference Proceedings (OSTI)

Magnesium has been used successfully in primary batteries, but its use in rechargeable cells has been stymied by the lack of suitable non-aqueous electrolyte that can conduct Mg+2 species, combined with poor stripping and plating properties. The development of a suitable cathode material for rechargeable magnesium batteries has also been a roadblock, but a nonflammable electrolyte is key. Likewise, the development of safe high voltage electrochemical supercapaitors has been stymied by the use of flammable solvents in the liquid electrolyte; to wit, acetonitrile. The purpose of the research conducted in this effort was to identify useful compositions of magnesium salts and polyphosphate solvents that would enable magnesium ions to be cycled within a secondary battery design. The polyphosphate solvents would provide the solvent for the magnesium salts while preventing the electrolyte from being flammable. This would enable these novel electrolytes to be considered as an alternative to THF-based electrolytes. In addition, we explored several of these solvents together with lithium slats for use as high voltage electrolytes for carbon-based electrochemical supercapacitors. The research was successful in that: 1) Magnesium imide dissolved in a phosphate ester solvent that contains a halogented phosphate ester appears to be the preferred electrolyte for a rechargeable Mg cell. 2) A combination of B-doped CNTs and vanadium phosphate appear to be the cathode of choice for a rechargeable Mg cell by virtue of higher voltage and better reversibility. 3) Magnesium alloys appear to perform better than pure magnesium when used in combination with the novel polyphosphate electrolytes. Also, this effort has established that Phoenix Innovationâ??s family of phosphonate/phosphate electrolytes together with specific lithium slats can be used in supercapacitor systems at voltages of greater than 10V.

Dr. Brian Dixon

2008-12-30T23:59:59.000Z

68

Crown Ethers in Nonaqueous Electrolytes for Lithium/Air Batteries  

SciTech Connect

The effects of three crown ethers, 12-crown-4, 15-crown-5, and 18-crown-6, as additives and co-solvents in non-aqueous electrolytes on the cell performance of primary Li/air batteries operated in a dry air environment were investigated. Crown ethers have large effects on the discharge performance of non-aqueous electrolytes in Li/air batteries. A small amount (normally less than 10% by weight or volume in electrolytes) of 12-Crown-4 and 15-crown-5 reduces the battery performance and a minimum discharge capacity appears at the crown ether content of ca. 5% in the electrolytes. However, when the content increases to about 15%, both crown ethers improve the capacity of Li/air cells by about 28% and 16%, respectively. 15-Crown-5 based electrolytes even show a maximum discharge capacity in the crown ether content range from 10% to 15%. On the other hand, the increase of 18-crown-6 amount in the electrolytes continuously lowers of the cell performance. The different battery performances of these three crown ethers in electrolytes are explained by the combined effects from the electrolytes’ contact angle, oxygen solubility, viscosity, ionic conductivity, and the stability of complexes formed between crown ether molecules and lithium ions.

Xu, Wu; Xiao, Jie; Wang, Deyu; Zhang, Jian; Zhang, Jiguang

2010-02-04T23:59:59.000Z

69

Nanoporous polymer electrolyte  

DOE Patents (OSTI)

A nanoporous polymer electrolyte and methods for making the polymer electrolyte are disclosed. The polymer electrolyte comprises a crosslinked self-assembly of a polymerizable salt surfactant, wherein the crosslinked self-assembly includes nanopores and wherein the crosslinked self-assembly has a conductivity of at least 1.0.times.10.sup.-6 S/cm at 25.degree. C. The method of making a polymer electrolyte comprises providing a polymerizable salt surfactant. The method further comprises crosslinking the polymerizable salt surfactant to form a nanoporous polymer electrolyte.

Elliott, Brian (Wheat Ridge, CO); Nguyen, Vinh (Wheat Ridge, CO)

2012-04-24T23:59:59.000Z

70

Electrolyte vapor condenser  

DOE Patents (OSTI)

A system is disclosed for removing electrolyte from a fuel cell gas stream. The gas stream containing electrolyte vapor is supercooled utilizing conventional heat exchangers and the thus supercooled gas stream is passed over high surface area passive condensers. The condensed electrolyte is then drained from the condenser and the remainder of the gas stream passed on. The system is particularly useful for electrolytes such as phosphoric acid and molten carbonate, but can be used for other electrolyte cells and simple vapor separation as well. 3 figs.

Sederquist, R.A.; Szydlowski, D.F.; Sawyer, R.D.

1983-02-08T23:59:59.000Z

71

Electrolyte vapor condenser  

DOE Patents (OSTI)

A system is disclosed for removing electrolyte from a fuel cell gas stream. The gas stream containing electrolyte vapor is supercooled utilizing conventional heat exchangers and the thus supercooled gas stream is passed over high surface area passive condensers. The condensed electrolyte is then drained from the condenser and the remainder of the gas stream passed on. The system is particularly useful for electrolytes such as phosphoric acid and molten carbonate, but can be used for other electrolyte cells and simple vapor separation as well.

Sederquist, Richard A. (Newington, CT); Szydlowski, Donald F. (East Hartford, CT); Sawyer, Richard D. (Canton, CT)

1983-01-01T23:59:59.000Z

72

Electrolyte additive for improved battery performance  

DOE Patents (OSTI)

In one embodiment of the present invention, there is provided an electrochemical cell having a metal bromine couple. The cell includes an electrode structure on which to deposit the metal of the couple and a counterelectrode at which to generate bromine. A microporous membrane separates the electrode and counterelectrode. Importantly, the aqueous electrolyte comprises an aqueous metal bromide solution containing a water soluble bromine complexing agent capable of forming a water immiscible complex with bromine and an additive capable of decreasing the wettability of the microporous separators employed in such cells by such water immiscible bromine complexes.

Bellows, Richard J. (Hampton, NJ); Kantner, Edward (E. Brunswick, NJ)

1989-04-04T23:59:59.000Z

73

Surface kinetic model for isotopic and trace element fractionation during precipitation of calcite from aqueous solution  

SciTech Connect

A surface reaction kinetic model is developed for predicting Ca isotope fractionation and metal/Ca ratios of calcite as a function of rate of precipitation from aqueous solution. The model is based on the requirements for dynamic equilibrium; i.e. proximity to equilibrium conditions is determined by the ratio of the net precipitation rate (R{sub p}) to the gross forward precipitation rate (R{sub f}), for conditions where ionic transport to the growing crystal surface is not rate-limiting. The value of R{sub p} has been experimentally measured under varying conditions, but the magnitude of R{sub f} is not generally known, and may depend on several factors. It is posited that, for systems with no trace constituents that alter the surface chemistry, R{sub f} can be estimated from the bulk far-from-equilibrium dissolution rate of calcite (R{sub b} or k{sub b}), since at equilibrium R{sub f} = R{sub b}, and R{sub p} = 0. Hence it can be inferred that R{sub f} {approx} R{sub p} + R{sub b}. The dissolution rate of pure calcite is measureable and is known to be a function of temperature and pH. At given temperature and pH, equilibrium precipitation is approached when R{sub p} (= R{sub f} - R{sub b}) << R{sub b}. For precipitation rates high enough that R{sub p} >> R{sub b}, both isotopic and trace element partitioning are controlled by the kinetics of ion attachment to the mineral surface, which tend to favor more rapid incorporation of the light isotopes of Ca and discriminate weakly between trace metals and Ca. With varying precipitation rate, a transition region between equilibrium and kinetic control occurs near R{sub p} {approx} R{sub b} for Ca isotopic fractionation. According to this model, Ca isotopic data can be used to estimate R{sub f} for calcite precipitation. Mechanistic models for calcite precipitation indicate that the molecular exchange rate is not constant at constant T and pH, but rather is dependent also on solution saturation state and hence R{sub p}. Allowing R{sub b} to vary as R{sub p}{sup 1/2}, consistent with available precipitation rate studies, produces a better fit to some trace element and isotopic data than a model where R{sub b} is constant. This model can account for most of the experimental data in the literature on the dependence of {sup 44}Ca/{sup 40}Ca and metal/Ca fractionation in calcite as a function of precipitation rate and temperature, and also accounts for {sup 18}O/{sup 16}O variations with some assumptions. The apparent temperature dependence of Ca isotope fractionation in calcite may stem from the dependence of R{sub b} on temperature; there should be analogous pH dependence at pH < 6. The proposed model may be valuable for predicting the behavior of isotopic and trace element fractionation for a range of elements of interest in low-temperature aqueous geochemistry. The theory presented is based on measureable thermo-kinetic parameters in contrast to models that equire hyper-fast diffusivity in near-surface layers of the solid.

DePaolo, D.

2010-10-15T23:59:59.000Z

74

Electrolytes for power sources  

DOE Patents (OSTI)

Electrolytes for power sources, particularly alkaline and acidic power sources, comprising benzene polysulfonic acids and benzene polyphosphonic acids or salts of such acids.

Doddapaneni, Narayan (Albuquerque, NM); Ingersoll, David (Albuquerque, NM)

1995-01-01T23:59:59.000Z

75

Electrolytes for power sources  

DOE Patents (OSTI)

Electrolytes are disclosed for power sources, particularly alkaline and acidic power sources, comprising benzene polysulfonic acids and benzene polyphosphonic acids or salts of such acids. 7 figures.

Doddapaneni, N.; Ingersoll, D.

1995-01-03T23:59:59.000Z

76

Electrolyte additive for lithium rechargeable organic electrolyte battery  

DOE Patents (OSTI)

A large excess of lithium iodide in solution is used as an electrolyte adive to provide overcharge protection for a lithium rechargeable organic electrolyte battery.

Behl, Wishvender K. (Ocean, NJ); Chin, Der-Tau (Winthrop, NY)

1989-01-01T23:59:59.000Z

77

Molten salt electrolyte separator  

DOE Patents (OSTI)

The patent describes a molten salt electrolyte/separator for battery and related electrochemical systems including a molten electrolyte composition and an electrically insulating solid salt dispersed therein, to provide improved performance at higher current densities and alternate designs through ease of fabrication. 5 figs.

Kaun, T.D.

1996-07-09T23:59:59.000Z

78

Electrolytic cell stack with molten electrolyte migration control  

DOE Patents (OSTI)

An electrolytic cell stack includes inactive electrolyte reservoirs at the upper and lower end portions thereof. The reservoirs are separated from the stack of the complete cells by impermeable, electrically conductive separators. Reservoirs at the negative end are initially low in electrolyte and the reservoirs at the positive end are high in electrolyte fill. During stack operation electrolyte migration from the positive to the negative end will be offset by the inactive reservoir capacity. In combination with the inactive reservoirs, a sealing member of high porosity and low electrolyte retention is employed to limit the electrolyte migration rate. 5 figs.

Kunz, H.R.; Guthrie, R.J.; Katz, M.

1987-03-17T23:59:59.000Z

79

Nano Res (2010) 3: 452458452 Aqueous Supercapacitors on Conductive Cotton  

E-Print Network (OSTI)

Nano Res (2010) 3: 452­458452 Aqueous Supercapacitors on Conductive Cotton Mauro Pasta1,2 , Fabio the fabrication of wearable supercapacitors using cotton fabric as an essential component. Carbon nanotubes in the supercapacitor. Aqueous lithium sulfate is used as the electrolyte in the devices, because it presents no safety

Cui, Yi

80

Electric current-producing device having sulfone-based electrolyte  

DOE Patents (OSTI)

Electrolytic solvents and applications of such solvents including electric current-producing devices. For example, a solvent can include a sulfone compound of R1--SO2--R2, with R1 being an alkyl group and R2 a partially oxygenated alkyl group, to exhibit high chemical and thermal stability and high oxidation resistance. For another example, a battery can include, between an anode and a cathode, an electrolyte which includes ionic electrolyte salts and a non-aqueous electrolyte solvent which includes a non-symmetrical, non-cyclic sulfone. The sulfone has a formula of R1--SO2--R2, wherein R1 is a linear or branched alkyl or partially or fully fluorinated linear or branched alkyl group having 1 to 7 carbon atoms, and R2 is a linear or branched or partially or fully fluorinated linear or branched oxygen containing alkyl group having 1 to 7 carbon atoms. The electrolyte can include an electrolyte co-solvent and an electrolyte additive for protective layer formation.

Angell, Charles Austen (Mesa, AZ); Sun, Xiao-Guang (Tempe, AZ)

2010-11-16T23:59:59.000Z

Note: This page contains sample records for the topic "aqueous electrolyte modeling" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Level 1 transient model for a molybdenum-99 producing aqueous homogeneous reactor and its applicability to the tracy reactor  

SciTech Connect

Babcock and Wilcox Technical Services Group (B and W) has identified aqueous homogeneous reactors (AHRs) as a technology well suited to produce the medical isotope molybdenum 99 (Mo-99). AHRs have never been specifically designed or built for this specialized purpose. However, AHRs have a proven history of being safe research reactors. In fact, in 1958, AHRs had 'a longer history of operation than any other type of research reactor using enriched fuel' and had 'experimentally demonstrated to be among the safest of all various type of research reactor now in use [1].' A 'Level 1' model representing B and W's proposed Medical Isotope Production System (MIPS) reactor has been developed. The Level 1 model couples a series of differential equations representing neutronics, temperature, and voiding. Neutronics are represented by point reactor kinetics while temperature and voiding terms are axially varying (one-dimensional). While this model was developed specifically for the MIPS reactor, its applicability to the Japanese TRACY reactor was assessed. The results from the Level 1 model were in good agreement with TRACY experimental data and found to be conservative over most of the time domains considered. The Level 1 model was used to study the MIPS reactor. An analysis showed the Level 1 model agreed well with a more complex computational model of the MIPS reactor (a FETCH model). Finally, a significant reactivity insertion was simulated with the Level 1 model to study the MIPS reactor's time-dependent response. (authors)

Nygaard, E. T. [Babcock and Wilcox Technical Services Group, 800 Main Street, Lynchburg, VA 24504 (United States); Williams, M. M. R. [Imperial College London, SW7 2AZ (United Kingdom); Angelo, P. L. [Y-12 National Security Complex, Oak Ridge, TN 37831 (United States)

2012-07-01T23:59:59.000Z

82

Task 1: Modeling Study of CO Effects on Polymer Electrolyte Fuel Cell Anodes Task 2: Study of Ac Impedance as Membrane/Electrode Manufacturing Diagnostic Tool  

DOE Green Energy (OSTI)

Carbon monoxide poisoning of polymer electrolyte fuel cell anodes is a key problem to be overcome when operating a polymer electrolyte fuel cell (PEFC) on reformed fuels. CO adsorbs preferentially on the precious metal surface leading to substantial performance losses. Some recent work has explored this problem, primarily using various Pt alloys in attempts to lower the degree of surface deactivation. In their studies of hydrogen oxidation on Pt and Pt alloy (Pt/Sn, Pt/Ru) rotating disk electrodes exposed to H{sub 2}/CO mixtures, Gasteiger et al. showed that a small hydrogen oxidation current is observed well before the onset of major CO oxidative stripping (ca. 0.4 V) on Pt/Ru. However, these workers concluded that such current observed at low anode overpotentials was too low to be of practical value. Nonetheless, MST-11 researchers and others have found experimentally that it is possible to run a PEFC, e.g., with a Pt/Ru anode, in the presence of CO levels in the range 10--100 ppm with little voltage loss. Such experimental results suggest that, in fact, PEFC operation at significant current densities under low anode overpotentials is possible in the presence of such levels of CO, even before resorting to air bleeding into the anode feed stream. The latter approach has been shown to be effective in elimination of Pt anode catalyst poisoning effects at CO levels of 20--50 ppm for cells operating at 80 C with low Pt catalyst loading. The effect of oxygen bleeding is basically to lower P{sub CO} down to extremely low levels in the anode plenum thanks to the catalytic (chemical) oxidation of CO by dioxygen at the anode catalyst. In this modeling work the authors do not include specific description of oxygen bleeding effects and concentrate on the behavior of the anode with feed streams of H{sub 2} or reformate containing low levels of CO. The anode loss is treated in this work as a hydrogen and carbon monoxide electrode kinetics problem, but includes the effects of dilution of the feedstream with significant fractions of carbon dioxide and nitrogen and of mass transport losses in the gas diffusion backing. Not included in the anode model are ionic resistance and diffusion losses in the catalyst layer. They are looking to see if the overall pattern of polarization curves calculated based on such a purely kinetic model indeed mimics the central features of polarization curves observed for PEFCs operating on hydrogen with low levels of CO.

Thomas E. Springer

1998-01-30T23:59:59.000Z

83

Microscopic Insights into the Electrochemical Behavior of Nonaqueous Electrolytes in Electric Double-Layer Capacitors  

Science Conference Proceedings (OSTI)

Electric double-layer capacitors (EDLCs) are electrical devices that store energy by adsorption of ionic species at the inner surface of porous electrodes. Compared with aqueous electrolytes, ionic liquid and organic electrolytes have the advantage of larger potential windows, making them attractive for the next generation of EDLCs with superior energy and power densities. The performance of both ionic liquid and organic electrolyte EDLCs hinges on the judicious selection of the electrode pore size and the electrolyte composition, which requires a comprehension of the charging behavior from a microscopic view. In this Perspective, we discuss predictions from the classical density functional theory (CDFT) on the dependence of the capacitance on the pore size for ionic liquid and organic electrolyte EDLCs. CDFT is applicable to electrodes with the pore size ranging from that below the ionic dimensionality to mesoscopic scales, thus unique for investigating the electrochemical behavior of the confined electrolytes for EDLC applications.

Jiang, Deen [ORNL; Wu, Jianzhong [University of California, Riverside

2013-01-01T23:59:59.000Z

84

Solid Lithium Ion Conducting Electrolytes Suitable for ...  

Batteries with solid lithium ion conducting electrolytes would ... The invention is cost-effective and suitable for manufacturing solid electrolyte ...

85

Improved electrolytes for fuel cells  

DOE Green Energy (OSTI)

Present day fuel cells based upon hydrogen and oxygen have limited performance due to the use of phosphoric acid as an electrolyte. Improved performance is desirable in electrolyte conductivity, electrolyte management, oxygen solubility, and the kinetics of the reduction of oxygen. Attention has turned to fluorosulfonic acids as additives or substitute electrolytes to improve fuel cell performance. The purpose of this project is to synthesize and electrochemically evaluate new fluorosulfonic acids as superior alternatives to phosphoric acid in fuel cells. (VC)

Gard, G.L.; Roe, D.K.

1991-06-01T23:59:59.000Z

86

Batteries using molten salt electrolyte  

SciTech Connect

An electrolyte system suitable for a molten salt electrolyte battery is described where the electrolyte system is a molten nitrate compound, an organic compound containing dissolved lithium salts, or a 1-ethyl-3-methlyimidazolium salt with a melting temperature between approximately room temperature and approximately 250.degree. C. With a compatible anode and cathode, the electrolyte system is utilized in a battery as a power source suitable for oil/gas borehole applications and in heat sensors.

Guidotti, Ronald A. (Albuquerque, NM)

2003-04-08T23:59:59.000Z

87

Experimental studies in high temperature aqueous chemistry at Oak Ridge National Laboratory  

DOE Green Energy (OSTI)

Experimental research is conducted and models developed in a long- standing program at Oak Ridge on aqueous chemistry at high temperatures of broad classes of electrolytes emphasizing thermodynamics of reaction equilibria and excess thermodynamic properties of electrolytes. Experimental methods, their capabilities, data analysis, and results are summarized. Relevance of the work to problems in power plants, natural and industrial processes as well as basic solution chemistry and geochemistry are given. Progress in potentiometry, electrical conductivity, flow calorimetry, and isopiestic research is described. Future in this field demands greater precision in measurements and significant gains in our understanding of the solvation phenomena especially in the vicinity and beyond the critical point for water. The communities who do research on scattering, spectroscopy, and computer simulations can help guide these efforts through studies at extreme conditions.

Mesmer, R.E.; Palmer, D.A.; Simonson, J.M.; Holmes, H.F.; Ho, P.C.; Wesolowski, D.J.; Gruszkiewicz, M.S.

1996-01-01T23:59:59.000Z

88

Electrolytic tritium production  

SciTech Connect

This paper reports fifty-three electrolytic cells of various configurations and electrode compositions examined for tritium production. Significant tritium was found in 11 cells at levels between 1.5 and 80 times the starting concentration after enrichment corrections are made.

Storms, E.; Talcott, C. (Los Alamos National Lab., Nuclear Materials Technology Div. and Material Science and Technology Div., MS C348, Los Alamos, NM (US))

1990-07-01T23:59:59.000Z

89

Spin coating of electrolytes  

DOE Patents (OSTI)

Methods for spin coating electrolytic materials onto substrates are disclosed. More particularly, methods for depositing solid coatings of ion-conducting material onto planar substrates and onto electrodes are disclosed. These spin coating methods are employed to fabricate electrochemical sensors for use in measuring, detecting and quantifying gases and liquids.

Stetter, Joseph R. (Naperville, IL); Maclay, G. Jordan (Maywood, IL)

1989-01-01T23:59:59.000Z

90

Experimental investigation and thermodynamic modeling of extraction of heavy metal ions from aqueous solutions by chelation in supercritical carbon dioxide  

E-Print Network (OSTI)

Wastewater streams containing heavy metals are common in industry. To prevent the contamination of clean water sources, the Clean Water Act specifies limits on the heavy metal concentrations of industrial waste water. This creates a strong need for developing cost effective and environmentally friendly metal removal technologies. Solvent extraction has been recognized as one of the best methods for removing metals from wastewater. Although the metals are easily removed, this process has two major disadvantages. First, the solvent/metal solution must be subsequently purified. Second, since the solvent may be miscible in the aqueous phase, the residual solvent must be removed from the water stream. These disadvantages can be eliminated by substituting conventional organic solvents with supercritical fluids. The main objective of this research has been to investigate the potential and feasibility of heavy metal ion extraction through chelation in supercritical CO2. Copper has been chosen as the model contaminant as it is frequently found in industrial waste streams. Different chelating agents have been tested to find the most appropriate one for copper. Analytical methods have been developed to quantify supercritical and aqueous phase compositions. Specifically, an Atomic Absorption Analyzer and a Gas Chromatograph have been employed. Copper ions have been successfully extracted up to 97% on different isotherms. Considering the phase equilibria and the thirteen reactions taking place in the system, a thermodynamic model has been developed. This model predicts the system pH which is a important factor in design of metal extraction units. With the model the efficiency of the extraction with different chelating agents at different temperatures and pressures is easily estimated. The model is also capable of calculating the concentrations of chemical species present in the system. This study proposed a novel and viable technique for the remediation of metal ions in waste water streams. In conjunction with the developed model the efficiency of this process for a specific industrial application can be accurately estimated. The results of this study demonstrate that this process is both environmentally friendly and economically feasible for wide spread industrial use.

Uyansoy, Hakki

1995-01-01T23:59:59.000Z

91

Synthesis and Electrochemical Performance of a Lithium Titanium Phosphate Anode for Aqueous Lithium-Ion Batteries  

E-Print Network (OSTI)

Synthesis and Electrochemical Performance of a Lithium Titanium Phosphate Anode for Aqueous Lithium** Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, USA Lithium cells that use organic electrolytes. The equilibrium reaction potential of lithium titanium phosphate

Cui, Yi

92

Novel electrolyte chemistries for Mg-Ni rechargeable batteries.  

DOE Green Energy (OSTI)

Commercial hybrid electric vehicles (HEV) and battery electric vehicles (BEV) serve as means to reduce the nation's dependence on oil. Current electric vehicles use relatively heavy nickel metal hydride (Ni-MH) rechargeable batteries. Li-ion rechargeable batteries have been developed extensively as the replacement; however, the high cost and safety concerns are still issues to be resolved before large-scale production. In this study, we propose a new highly conductive solid polymer electrolyte for Mg-Ni high electrochemical capacity batteries. The traditional corrosive alkaline aqueous electrolyte (KOH) is replaced with a dry polymer with conductivity on the order of 10{sup -2} S/cm, as measured by impedance spectroscopy. Several potential novel polymer and polymer composite candidates are presented with the best-performing electrolyte results for full cell testing and cycling.

Garcia-Diaz, Brenda (Savannah River National Laboratory); Kane, Marie; Au, Ming (Savannah River National Laboratory)

2010-10-01T23:59:59.000Z

93

Definition: Electrolyte | Open Energy Information  

Open Energy Info (EERE)

Electrolyte Electrolyte Jump to: navigation, search Dictionary.png Electrolyte A substance that conducts charged ions from one electrode to the other in a fuel cell, battery, or electrolyzer.[1] View on Wikipedia Wikipedia Definition An electrolyte is a compound that ionizes when dissolved in suitable ionizing solvents such as water. This includes most soluble salts, acids, and bases. Some gases, such as hydrogen chloride, under conditions of high temperature or low pressure can also function as electrolytes. Electrolyte solutions can also result from the dissolution of some biological and synthetic polymers, termed polyelectrolytes, which contain charged functional groups. Electrolyte solutions are normally formed when a salt is placed into a solvent such as water and the individual components

94

Carbon nanotubes and graphene in aqueous surfactant solutions : molecular simulations and theoretical modeling  

E-Print Network (OSTI)

This thesis describes combined molecular simulations and theoretical modeling studies, supported by experimental observations, on properties and applications of carbon nanotubes (CNTs) and graphene sheets dispersed in ...

Lin, Shangchao

2012-01-01T23:59:59.000Z

95

Electro-hydrodynamics of binary electrolytes driven by modulated surface potentials  

E-Print Network (OSTI)

We study the electro-hydrodynamics of the Debye screening layer that arises in an aqueous binary solution near a planar insulating wall when applying a spatially modulated AC-voltage. Combining this with first order perturbation theory we establish the governing equations for the full non-equilibrium problem and obtain analytic solutions in the bulk for the pressure and velocity fields of the electrolyte and for the electric potential. We find good agreement between the numerics of the full problem and the analytics of the linear theory. Our work provides the theoretical foundations of circuit models discussed in the literature. The non-equilibrium approach also reveals unexpected high-frequency dynamics not predicted by circuit models.

N. A. Mortensen; L. H. Olesen; L. Belmon; H. Bruus

2004-07-07T23:59:59.000Z

96

Solid polymer electrolytes  

DOE Patents (OSTI)

This invention relates to Li ion (Li{sup +}) conductive solid polymer electrolytes composed of poly(vinyl sulfone) and lithium salts, and their use in all-solid-state rechargeable lithium ion batteries. The lithium salts comprise low lattice energy lithium salts such as LiN(CF{sub 3}SO{sub 2}){sub 2}, LiAsF{sub 6}, and LiClO{sub 4}. 2 figs.

Abraham, K.M.; Alamgir, M.; Choe, H.S.

1995-12-12T23:59:59.000Z

97

Ice electrode electrolytic cell  

DOE Patents (OSTI)

This invention relates to a method and apparatus for removing heavy metals from waste water, soils, or process streams by electrolytic cell means. The method includes cooling a cell cathode to form an ice layer over the cathode and then applying an electric current to deposit a layer of the heavy metal over the ice. The metal is then easily removed after melting the ice. In a second embodiment, the same ice-covered electrode can be employed to form powdered metals.

Glenn, David F. (Idaho Falls, ID); Suciu, Dan F. (Idaho Falls, ID); Harris, Taryl L. (Idaho Falls, ID); Ingram, Jani C. (Idaho Falls, ID)

1993-01-01T23:59:59.000Z

98

Ice electrode electrolytic cell  

DOE Patents (OSTI)

This invention relates to a method and apparatus for removing heavy metals from waste water, soils, or process streams by electrolytic cell means. The method includes cooling a cell cathode to form an ice layer over the cathode and then applying an electric current to deposit a layer of the heavy metal over the ice. The metal is then easily removed after melting the ice. In a second embodiment, the same ice-covered electrode can be employed to form powdered metals.

Glenn, D.F.; Suciu, D.F.; Harris, T.L.; Ingram, J.C.

1993-04-06T23:59:59.000Z

99

Solid polymer electrolytes  

DOE Patents (OSTI)

This invention relates to Li ion (Li.sup.+) conductive solid polymer electrolytes composed of poly(vinyl sulfone) and lithium salts, and their use in all-solid-state rechargeable lithium ion batteries. The lithium salts comprise low lattice energy lithium salts such as LiN(CF.sub.3 SO.sub.2).sub.2, LiAsF.sub.6, and LiClO.sub.4.

Abraham, Kuzhikalail M. (Needham, MA); Alamgir, Mohamed (Dedham, MA); Choe, Hyoun S. (Waltham, MA)

1995-01-01T23:59:59.000Z

100

Ice electrode electrolytic cell  

DOE Patents (OSTI)

This invention relates to a method and apparatus for removing heavy metals from waste water, soils, or process streams by electrolytic cell means. The method includes cooling a cell cathode to form an ice layer over the cathode and then applying an electric current to deposit a layer of the heavy metal over the ice. The metal is then easily removed after melting the ice. In a second embodiment, the same ice-covered electrode can be employed to form powdered metals.

Glenn, D.F.; Suciu, D.F.; Harris, T.L.; Ingram, J.C.

1992-12-31T23:59:59.000Z

Note: This page contains sample records for the topic "aqueous electrolyte modeling" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Lithium ion conducting electrolytes  

DOE Patents (OSTI)

A liquid, predominantly lithium-conducting, ionic electrolyte having exceptionally high conductivity at temperatures of 100.degree. C. or lower, including room temperature, and comprising the lithium salts selected from the group consisting of the thiocyanate, iodide, bromide, chloride, perchlorate, acetate, tetrafluoroborate, perfluoromethane sulfonate, perfluoromethane sulfonamide, tetrahaloaluminate, and heptahaloaluminate salts of lithium, with or without a magnesium-salt selected from the group consisting of the perchlorate and acetate salts of magnesium. Certain of the latter embodiments may also contain molecular additives from the group of acetonitrile (CH.sub.3 CN) succinnonitrile (CH.sub.2 CN).sub.2, and tetraglyme (CH.sub.3 --O--CH.sub.2 --CH.sub.2 --O--).sub.2 (or like solvents) solvated to a Mg.sup.+2 cation to lower the freezing point of the electrolyte below room temperature. Other particularly useful embodiments contain up to about 40, but preferably not more than about 25, mol percent of a long chain polyether polymer dissolved in the lithium salts to provide an elastic or rubbery solid electrolyte of high ambient temperature conductivity and exceptional 100.degree. C. conductivity. Another embodiment contains up to about but not more than 10 mol percent of a molecular solvent such as acetone.

Angell, C. Austen (Tempe, AZ); Liu, Changle (Tempe, AZ)

1996-01-01T23:59:59.000Z

102

Separation of metal ions from aqueous solutions  

DOE Patents (OSTI)

This invention is comprised of a process and apparatus for quantitatively and selectively separating metal ions from mixtures thereof in aqueous solution. The apparatus includes, in combination, a horizontal electrochemical flowing cell containing flowing bulk electrolyte solution and an aqueous, metal ion-containing solution, the cell containing a metal mesh working electrode, a counter electrode positioned downstream from the working electrode, an independent variable power supply/potentiostat positioned outside of the flowing cell and connected to the electrodes, and optionally a detector such as a chromatographic detector, positioned outside the flowing cell. This apparatus and its operation has significant application where trace amounts of metal ions are to be separated.

Almon, A.

1991-12-31T23:59:59.000Z

103

Modeling and Optimization of PEMFC Systems and its Application to Direct Hydrogen Fuel Cell Vehicles  

E-Print Network (OSTI)

Polymer Electrolyte Fuel Cell Model, J. Electrochem. Soc. ,in Polymer Electrolyte Fuel Cells, J. Electrochem. Soc. ,Solid-Polymer- Electrolyte Fuel Cell, J. Electrochem. Soc. ,

Zhao, Hengbing; Burke, Andy

2008-01-01T23:59:59.000Z

104

Inorganic rechargeable non-aqueous cell  

DOE Patents (OSTI)

A totally inorganic non-aqueous rechargeable cell having an alkali or alkaline earth metal anode such as of lithium, a sulfur dioxide containing electrolyte and a discharging metal halide cathode, such as of CuCl.sub.2, CuBr.sub.2 and the like with said metal halide being substantially totally insoluble in SO.sub.2 and admixed with a conductive carbon material.

Bowden, William L. (Nashua, NH); Dey, Arabinda N. (Needham, MA)

1985-05-07T23:59:59.000Z

105

Pseudo-capacitor device for aqueous electrolytes - Energy ...  

A pseudo-capacitor having a high energy storage capacity develops a double layer capacitance as well as a Faradaic or battery-like redox reaction, also referred to as ...

106

Electrochemical Windows of Sulfone-Based Electrolytes for High-Voltage Li-Ion Batteries  

Science Conference Proceedings (OSTI)

Further development of high-voltage lithium-ion batteries requires electrolytes with electrochemical windows greater than 5 V. Sulfone-based electrolytes are promising for such a purpose. Here we compute the electrochemical windows for experimentally tested sulfone electrolytes by different levels of theory in combination with various solvation models. The MP2 method combined with the polarizable continuum model is shown to be the most accurate method to predict oxidation potentials of sulfone-based electrolytes with mean deviation less than 0.29 V. Mulliken charge analysis shows that the oxidation happens on the sulfone group for ethylmethyl sulfone and tetramethylene sulfone, and on the ether group for ether functionalized sulfones. Large electrochemical windows of sulfone-based electrolytes are mainly contributed by the sulfone group in the molecules which helps lower the HOMO level. This study can help understand the voltage limits imposed by the sulfone-based electrolytes and aid in designing new electrolytes with greater electrochemical windows.

Shao, Nan [ORNL; Sun, Xiao-Guang [ORNL; Dai, Sheng [ORNL; Jiang, Deen [ORNL

2011-01-01T23:59:59.000Z

107

Glass electrolyte composition  

DOE Patents (OSTI)

An ionically conductive glass is disclosed for use as electrolyte in a high temperature electrochemical cell, particularly a cell with sodium anode and sulfur cathode. The glass includes the constituents Na/sub 2/O, ZrO/sub 2/, Al/sub 2/O/sub 3/ and SiO/sub 2/ in selected proportions to be a single phase solid solution substantially free of crystalline regions and undissolved constituents. Other advantageous properties are an ionic conductivity in excess of 2 x 10/sup -3/ (ohm-cm)/sup -1/ at 300/sup 0/C and a glass transition temperature in excess of 500/sup 0/C.

Kucera, G.H.; Roche, M.F.

1985-01-08T23:59:59.000Z

108

DOE workshop: Sedimentary systems, aqueous and organic geochemistry  

SciTech Connect

A DOE workshop on sedimentary systems, aqueous and organic geochemistry was held July 15-16, 1993 at Lawrence Berkeley Laboratory. Papers were organized into several sections: Fundamental Properties, containing papers on the thermodynamics of brines, minerals and aqueous electrolyte solutions; Geochemical Transport, covering 3-D imaging of drill core samples, hydrothermal geochemistry, chemical interactions in hydrocarbon reservoirs, fluid flow model application, among others; Rock-Water Interactions, with presentations on stable isotope systematics of fluid/rock interaction, fluid flow and petotectonic evolution, grain boundary transport, sulfur incorporation, tracers in geologic reservoirs, geothermal controls on oil-reservoir evolution, and mineral hydrolysis kinetics; Organic Geochemistry covered new methods for constraining time of hydrocarbon migration, kinetic models of petroleum formation, mudstones in burial diagenesis, compound-specific carbon isotope analysis of petroleums, stability of natural gas, sulfur in sedimentary organic matter, organic geochemistry of deep ocean sediments, direct speciation of metal by optical spectroscopies; and lastly, Sedimentary Systems, covering sequence stratigraphy, seismic reflectors and diagenetic changes in carbonates, geochemistry and origin of regional dolomites, and evidence of large comet or asteroid impacts at extinction boundaries.

Not Available

1993-07-01T23:59:59.000Z

109

DOE Hydrogen Analysis Repository: Electrolytic Hydrogen Production  

NLE Websites -- All DOE Office Websites (Extended Search)

by Principal Investigator Projects by Date U.S. Department of Energy Electrolytic Hydrogen Production Project Summary Full Title: Summary of Electrolytic Hydrogen Production:...

110

Electrolyte Materials for AMFCs and AMFC Performance  

NLE Websites -- All DOE Office Websites (Extended Search)

May 8 th 2011 AMFC Workshop 2011 AMFC WORKSHOP 2011 AMFC WORKSHOP Electrolyte Materials for AMFCs Electrolyte Materials for AMFCs and AMFC Performance and AMFC Performance May 8...

111

Block copolymer electrolytes for lithium batteries  

E-Print Network (OSTI)

of poly(ethylene oxide) molten-salt rubbery electrolytes.of poly(ethylene oxide) molten-salt rubbery electrolytes.

Hudson, William Rodgers

2011-01-01T23:59:59.000Z

112

Electrolyte treatment for aluminum reduction  

DOE Patents (OSTI)

A method of treating an electrolyte for use in the electrolytic reduction of alumina to aluminum employing an anode and a cathode, the alumina dissolved in the electrolyte, the treating improving wetting of the cathode with molten aluminum during electrolysis. The method comprises the steps of providing a molten electrolyte comprised of ALF.sub.3 and at least one salt selected from the group consisting of NaF, KF and LiF, and treating the electrolyte by providing therein 0.004 to 0.2 wt. % of a transition metal or transition metal compound for improved wettability of the cathode with molten aluminum during subsequent electrolysis to reduce alumina to aluminum.

Brown, Craig W. (Seattle, WA); Brooks, Richard J. (Seattle, WA); Frizzle, Patrick B. (Seattle, WA); Juric, Drago D. (Bulleen, AU)

2002-01-01T23:59:59.000Z

113

Electrolyte paste for molten carbonate fuel cells  

DOE Patents (OSTI)

The electrolyte matrix and electrolyte reservoir plates in a molten carbonate fuel cell power plant stack are filled with electrolyte by applying a paste of dry electrolyte powder entrained in a dissipatable carrier to the reactant flow channels in the current collector plate. The stack plates are preformed and solidified to final operating condition so that they are self sustaining and can be disposed one atop the other to form the power plant stack. Packing the reactant flow channels with the electrolyte paste allows the use of thinner electrode plates, particularly on the anode side of the cells. The use of the packed electrolyte paste provides sufficient electrolyte to fill the matrix and to entrain excess electrolyte in the electrode plates, which also serve as excess electrolyte reservoirs. When the stack is heated up to operating temperatures, the electrolyte in the paste melts, the carrier vaporizes, or chemically decomposes, and the melted electrolyte is absorbed into the matrix and electrode plates.

Bregoli, Lawrance J. (Southwick, MA); Pearson, Mark L. (New London, CT)

1995-01-01T23:59:59.000Z

114

Production of hydrogen. [metals oxidation/carbon reduction process; and cyyclic electrolytic; carbon reduction  

SciTech Connect

Hydrogen is produced in a cyclic metals oxidation/carbon reduction process. In particular, elemental iron or cobalt is oxidized in an aqueous solution of an alkali metal hydroxide with the simultaneous generation of hydrogen. The iron or cobalt oxidation products of the reaction are thereafter reduced to elemental iron or cobalt by contact with a carbonaceous reducing agent at elevated temperatures and the reduced material recycled for reoxidation. In an alternate operation, hydrogen is produced in a cyclic electrolytic/carbon reduction process wherein elemental iron or cobalt is electrolytically converted to corresponding oxidation products with the simultaneous generation of hydrogen. The electrolytic cell used in this process comprises a cathode, a magnetic anode that is adapted to attract and retain iron and/or cobalt particles and an aqueous electrolyte. In the electrolytic cell, hydrogen is produced at the cathode and metal particles contained on the magnetic electrode are oxidized to a non-ferromagnetic specie, such as ferrous hydroxide. The nonferromagnetic species are recovered from the electrolytic cell and thereafter reconverted to particulate elemental iron and/or cobalt by treating the material with a carbonaceous reductant at an elevated temperature.

Batzold, J.S.; Pan, Y.

1980-05-13T23:59:59.000Z

115

Electrolytic method for the production of lithium using a lithium-amalgam electrode  

DOE Patents (OSTI)

A method for recovering lithium from its molten amalgam by electrolysis of the amalgam in an electrolytic cell containing as a molten electrolyte a fused-salt consisting essentially of a mixture of two or more alkali metal halides, preferably alkali metal halides selected from lithium iodide, lithium chloride, potassium iodide and potassium chloride. A particularly suitable molten electrolyte is a fused-salt consisting essentially of a mixture of at least three components obtained by modifying an eutectic mixture of LiI-KI by the addition of a minor amount of one or more alkali metal halides. The lithium-amalgam fused-salt cell may be used in an electrolytic system for recovering lithium from an aqueous solution of a lithium compound, wherein electrolysis of the aqueous solution in an aqueous cell in the presence of a mercury cathode produces a lithium amalgam. The present method is particularly useful for the regeneration of lithium from the aqueous reaction products of a lithium-water-air battery.

Cooper, John F. (Castro Valley, CA); Krikorian, Oscar H. (Danville, CA); Homsy, Robert V. (Oakland, CA)

1979-01-01T23:59:59.000Z

116

Lithium ion conducting ionic electrolytes  

DOE Patents (OSTI)

A liquid, predominantly lithium-conducting, ionic electrolyte is described which has exceptionally high conductivity at temperatures of 100.degree. C. or lower, including room temperature. It comprises molten lithium salts or salt mixtures in which a small amount of an anionic polymer lithium salt is dissolved to stabilize the liquid against recrystallization. Further, a liquid ionic electrolyte which has been rubberized by addition of an extra proportion of anionic polymer, and which has good chemical and electrochemical stability, is described. This presents an attractive alternative to conventional salt-in-polymer electrolytes which are not cationic conductors.

Angell, C. Austen (Mesa, AZ); Xu, Kang (Tempe, AZ); Liu, Changle (Tulsa, OK)

1996-01-01T23:59:59.000Z

117

Solid polymer electrolyte lithium batteries  

DOE Patents (OSTI)

This invention pertains to Lithium batteries using Li ion (Li.sup.+) conductive solid polymer electrolytes composed of solvates of Li salts immobilized in a solid organic polymer matrix. In particular, this invention relates to Li batteries using solid polymer electrolytes derived by immobilizing solvates formed between a Li salt and an aprotic organic solvent (or mixture of such solvents) in poly(vinyl chloride).

Alamgir, Mohamed (Dedham, MA); Abraham, Kuzhikalail M. (Needham, MA)

1993-01-01T23:59:59.000Z

118

Solid polymer electrolyte lithium batteries  

DOE Patents (OSTI)

This invention pertains to Lithium batteries using Li ion (Li[sup +]) conductive solid polymer electrolytes composed of solvates of Li salts immobilized in a solid organic polymer matrix. In particular, this invention relates to Li batteries using solid polymer electrolytes derived by immobilizing solvates formed between a Li salt and an aprotic organic solvent (or mixture of such solvents) in poly(vinyl chloride). 3 figures.

Alamgir, M.; Abraham, K.M.

1993-10-12T23:59:59.000Z

119

Market potential for electrolytic hydrogen  

SciTech Connect

By the year 2000, the potential market for advanced-technology electrolytic hydrogen among specialty users is projected to be about half of what the merchant hydrogen market would be in the absence of electrolytic hydrogen. This potential market, representing an annual demand of about 16 billion SCF of hydrogen, will develop from market penetrations of electrolyzers assumed to begin in the early 1980s. 6 refs.

Fein, E.

1981-01-01T23:59:59.000Z

120

High cation transport polymer electrolyte  

DOE Patents (OSTI)

A solid state ion conducting electrolyte and a battery incorporating same. The electrolyte includes a polymer matrix with an alkali metal salt dissolved therein, the salt having an anion with a long or branched chain having not less than 5 carbon or silicon atoms therein. The polymer is preferably a polyether and the salt anion is preferably an alkyl or silyl moiety of from 5 to about 150 carbon/silicon atoms.

Gerald, II, Rex E. (Brookfield, IL); Rathke, Jerome W. (Homer Glen, IL); Klingler, Robert J. (Westmont, IL)

2007-06-05T23:59:59.000Z

Note: This page contains sample records for the topic "aqueous electrolyte modeling" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Aqueous Electrotechnologies: Progress in Theory and Practice - TMS  

Science Conference Proceedings (OSTI)

Aqueous Electrotechnologies: Progress in Theory and Practice ... catalyzed leaching, solvent extraction and ion exchange, and reactor modelling and design .

122

The rheology of oxide dispersions and the role of concentrated electrolyte solutions  

SciTech Connect

Stability control of particulate dispersions is critical to a wide range of industrial processes. In the UK nuclear industry, significant volumes of waste materials arising from the corrosion products of Magnox fuel rods currently require treatment and storage. The majority of this waste is present as aqueous dispersions of oxide particulates. Treatment of these dispersions will require a variety of unit operations including mobilisation, transport and solid- liquid separation. Typically these processes must operate across a narrow optimal range of pH and the dispersions are, almost without exception, found in complex electrolyte conditions of high overall concentration. Knowledge of the behaviour of oxides in various electrolyte conditions and over a large pH range is essential for the efficient design and control of any waste processing approach. The transport properties of particle dispersions are characterised by the rheological properties. It is well known that particle dispersion rheology is strongly influenced by particle-particle interaction forces, and that particle-particle interactions are strongly influenced by adsorbed ions on the particle surfaces. Here we correlate measurements of the shear yield stress and the particle zeta potentials to provide insight as to the role of ions in moderating particle interactions. The zeta potential of model TiO{sub 2} suspensions were determined (Colloidal Dynamics Zeta Probe) over a range of pH for a series of alkali metal halides and quaternary ammonium halides at a range of solution concentrations (0.001 M - 1 M). The results show some surprising co-ion effects at high electrolyte concentrations (>0.5 M) and indicate that even ions generally considered to be indifferent induce a shift in iso-electric point (i.e.p.) which is inferred as being due to specific adsorption of ions. The shear yield stress values of concentrated titania dispersions were measured using a Bohlin C-VOR stress controlled rheometer. The shear yield stress of a material is defined as the minimum applied shear stress required to induce flow. The yield stress vs. pH curves obtained reflected the shifts in i.e.p. seen in the zeta potential results. Interestingly, specific ion adsorption results in an unexplained increase in the value of the yield stress over that expected for simple systems with no such interfacial ion adsorption. Possible reasons for this effect such as ion-ion correlation effects are discussed. The importance of this increased attraction for the mobilisation of settled solids in an aqueous environment and especially the likely effects on the treatment of Magnox fuel waste materials is discussed. (authors)

Biggs, Simon; Tindley, Amy [Leeds University/Nexis Solutions URA in Particle Science and Technology, Institute of Particle Science and Engineering, School of Process, Environmental and Materials Engineering, The University of Leeds, Leeds LS2 9JT (United Kingdom)

2007-07-01T23:59:59.000Z

123

Aqueous Processing  

Science Conference Proceedings (OSTI)

"Cold-Weather Gold Heap-Leaching Operational Methods" (Overview), K.E. ..... " Tools for Optimizing Cu Electrodeposition: Modeling and Reagent Addition ...

124

Electrochemical behavior of LiCoO2 as aqueous lithium-ion battery electrodes Riccardo Ruffo a  

E-Print Network (OSTI)

Electrochemical behavior of LiCoO2 as aqueous lithium-ion battery electrodes Riccardo Ruffo 2008 Available online xxxx Keywords: LiCoO2 Aqueous electrolyte LiNO3 Lithium-ion battery Cathode substrate using the procedures typical for the study of electrodes for lithium-ion batteries in organic

Cui, Yi

125

IUPAC-NIST Solubility Data Series. 95. Alkaline Earth Carbonates in Aqueous Systems. Part 2. Ca  

Science Conference Proceedings (OSTI)

The alkaline earth carbonates are an important class of minerals. This article is part of a volume in the IUPAC-NIST Solubility Data Series that compiles and critically evaluates solubility data of the alkaline earth carbonates in water and in simple aqueous electrolyte solutions. Part 1 outlined the procedure adopted in this volume, and presented the beryllium and magnesium carbonates. Part 2, the current paper, compiles and critically evaluates the solubility data of calcium carbonate. The chemical forms included are the anhydrous CaCO{sub 3} types calcite, aragonite, and vaterite, the monohydrate monohydrocalcite (CaCO{sub 3}{center_dot} H{sub 2}O), the hexahydrate ikaite (CaCO{sub 3}{center_dot}6H{sub 2}O), and an amorphous form. The data were analyzed with two model variants, and thermodynamic data of each form consistent with each of the models and with the CODATA key values for thermodynamics are presented.

De Visscher, Alex; Vanderdeelen, Jan [Department of Chemical and Petroleum Engineering, and Centre for Environmental Engineering Research and Education (CEERE), Schulich School of Engineering, University of Calgary, Calgary, Alberta, T2N 1N4 (Canada); Department of Applied Analytical and Physical Chemistry, Faculty of Bioscience Engineering, Ghent University, B-9000 Ghent (Belgium)

2012-06-15T23:59:59.000Z

126

Anion exchange polymer electrolytes  

DOE Patents (OSTI)

Solid anion exchange polymer electrolytes and compositions comprising chemical compounds comprising a polymeric core, a spacer A, and a guanidine base, wherein said chemical compound is uniformly dispersed in a suitable solvent and has the structure: ##STR00001## wherein: i) A is a spacer having the structure O, S, SO.sub.2, --NH--, --N(CH.sub.2).sub.n, wherein n=1-10, --(CH.sub.2).sub.n--CH.sub.3--, wherein n=1-10, SO.sub.2-Ph, CO-Ph, ##STR00002## wherein R.sub.5, R.sub.6, R.sub.7 and R.sub.8 each are independently --H, --NH.sub.2, F, Cl, Br, CN, or a C.sub.1-C.sub.6 alkyl group, or any combination of thereof; ii) R.sub.9, R.sub.10, R.sub.11, R.sub.12, or R.sub.13 each independently are --H, --CH.sub.3, --NH.sub.2, --NO, --CH.sub.nCH.sub.3 where n=1-6, HC.dbd.O--, NH.sub.2C.dbd.O--, --CH.sub.nCOOH where n=1-6, --(CH.sub.2).sub.n--C(NH.sub.2)--COOH where n=1-6, --CH--(COOH)--CH.sub.2--COOH, --CH.sub.2--CH(O--CH.sub.2CH.sub.3).sub.2, --(C.dbd.S)--NH.sub.2, --(C.dbd.NH)--N--(CH.sub.2).sub.nCH.sub.3, where n=0-6, --NH--(C.dbd.S)--SH, --CH.sub.2--(C.dbd.O)--O--C(CH.sub.3).sub.3, --O--(CH.sub.2).sub.n--CH--(NH.sub.2)--COOH, where n=1-6, --(CH.sub.2).sub.n--CH.dbd.CH wherein n=1-6, --(CH.sub.2).sub.n--CH--CN wherein n=1-6, an aromatic group such as a phenyl, benzyl, phenoxy, methylbenzyl, nitrogen-substituted benzyl or phenyl groups, a halide, or halide-substituted methyl groups; and iii) wherein the composition is suitable for use in a membrane electrode assembly.

Kim, Yu Seung; Kim, Dae Sik; Lee, Kwan-Soo

2013-07-23T23:59:59.000Z

127

Liquid-gas separation in colloidal electrolytes  

E-Print Network (OSTI)

The liquid-gas transition of an electroneutral mixture of oppositely charged colloids, studied by Monte Carlo simulations, is found in the low temperature -- low density region. The critical temperature shows a non-monotonous behavior as a function of the interaction range, $\\kappa^{-1}$, with a maximum at $\\kappa \\sigma \\approx 10$, implying an island of coexistence in the $\\kappa$-$\\rho$ plane. The system is arranged in such a way that each particle is surrounded by shells of particles with alternating charge. In contrast with the electrolyte primitive model, both neutral and charged clusters are obtained in the vapor phase

Jose B. Caballero; Antonio M. Puertas; Antonio Fernandez-Barbero; F. Javier de las Nieves; J. M. Romero-Enrique; L. F. Rull

2005-08-10T23:59:59.000Z

128

Novel electrolyte additives to enhance zinc electrode cycle life  

DOE Green Energy (OSTI)

Electrochemical power sources that utilize zinc electrodes possess many advantages. Zinc is abundantly available, benign, inexpensive, stable over a wide operating temperature range, and has a high oxidation potential. In spite of these advantageous characteristics, rechargeable electrochemical systems based on zinc chemistry have not found widespread use. The major disadvantages of zinc electrodes are that they have limited cycle life due to zinc slumping and zinc electrode shape changes in alkaline solutions resulting from the solubility of zincate (Zn(OH){sub 4}{sup 2-}) in these solutions. As a result, premature cell failure often results due to cell shorting caused by dendritic growth as well as zinc slumping. In this paper we describe the chemical and physical characteristics of electrolyte solutions employing additives, particularly for zinc based electrochemical systems. These electrolytes are prepared using the alkali metal salts of 1,3,5-phenyltrisulfonic acid in combination with potassium hydroxide. The alkali metal salts of the acid possess good thermal stability, good ionic conductivity, and have a wide electrochemical voltage window in aqueous systems. With these electrolyte solutions improved cycle life was achieved in Zn/NiOOH and Zn/AgO. Improved cycle life with this additive is attributed to decreased zincate solubility, resulting in reduced zinc slumping and electrode shape changes. In addition, increased shelf-life and reduced self-discharge were also observed in many alkaline power sources.

Doddapaneni, N.; Ingersoll, D.

1995-11-01T23:59:59.000Z

129

LOWER TEMPERATURE ELECTROLYTE AND ELECTRODE MATERIALS  

DOE Green Energy (OSTI)

A thorough literature survey on low-temperature electrolyte and electrode materials for SOFC is given in this report. Thermodynamic stability of selected electrolyte and its chemical compatibility with cathode substrate were evaluated. Preliminary electrochemical characterizations were conducted on symmetrical cells consisting of the selected electrolyte and various electrode materials. Feasibility of plasma spraying new electrolyte material thin-film on cathode substrate was explored.

Keqin Huang

2003-04-30T23:59:59.000Z

130

Solid Lithium Ion Conducting Electrolytes Suitable for ...  

not applicable to an assembly line manufacturing process. The invention is cost-effective and suitable for manufacturing solid electrolyte

131

Degradation Mechanism of SOFC Cathode Electrolyte Systems ...  

Science Conference Proceedings (OSTI)

Presentation Title, Degradation Mechanism of SOFC Cathode Electrolyte Systems Incorporating Doped Lathanum Gallates. Author(s), Chuan Zhang, Anh T.

132

Rechargeable solid polymer electrolyte battery cell  

SciTech Connect

A rechargeable battery cell comprising first and second electrodes sandwiching a solid polymer electrolyte comprising a layer of a polymer blend of a highly conductive polymer and a solid polymer electrolyte adjacent said polymer blend and a layer of dry solid polymer electrolyte adjacent said layer of polymer blend and said second electrode.

Skotheim, Terji (East Patchoque, NY)

1985-01-01T23:59:59.000Z

133

ELECTROLYTIC SEPARATION PROCESS AND APPARATUS  

DOE Patents (OSTI)

A method is given for dissolving stainless steel-c lad fuel elements in dilute acids such as half normal sulfuric acid. The fuel element is made the anode in a Y-shaped electrolytic cell which has a flowing mercury cathode; the stainless steel elements are entrained in the mercury and stripped therefrom by a continuous process. (AEC)

McLain, M.E. Jr.; Roberts, M.W.

1962-03-01T23:59:59.000Z

134

Intermediate temperature electrolytes for SOFC  

DOE Green Energy (OSTI)

The objective of this work is to identify a new set of materials that would allow the operation of the solid oxide fuel cell in the 600--800{sup degrees}C temperature range. The approach that is being used is to start with a systematic evaluation of new electrolyte materials and then to develop compatible electrode and interconnect materials.

Bloom, I.; Krumpelt, M.; Hash, M.C.; Zebrowski, J.P.; Zurawski, D.

1992-01-01T23:59:59.000Z

135

Intermediate temperature electrolytes for SOFC  

DOE Green Energy (OSTI)

The objective of this work is to identify a new set of materials that would allow the operation of the solid oxide fuel cell in the 600--800{sup degrees}C temperature range. The approach that is being used is to start with a systematic evaluation of new electrolyte materials and then to develop compatible electrode and interconnect materials.

Bloom, I.; Krumpelt, M.; Hash, M.C.; Zebrowski, J.P.; Zurawski, D.

1992-09-01T23:59:59.000Z

136

Zinc electrode in alkaline electrolyte  

DOE Green Energy (OSTI)

The zinc electrode in alkaline electrolyte is unusual in that supersaturated zincate solutions can form during discharge and spongy or mossy zinc deposits can form on charge at low overvoltages. The effect of additives on regular pasted ZnO electrodes and calcium zincate electrodes is discussed. The paper also reports on in situ x-ray absorption (XAS) results on mossy zinc deposits.

McBreen, J.

1995-12-31T23:59:59.000Z

137

Solid lithium-ion electrolyte  

DOE Patents (OSTI)

The present invention relates to the composition of a solid lithium-ion electrolyte based on the Li.sub.2 O--CeO.sub.2 --SiO.sub.2 system having good transparent characteristics and high ion conductivity suitable for uses in lithium batteries, electrochromic devices and other electrochemical applications.

Zhang, Ji-Guang (Golden, CO); Benson, David K. (Golden, CO); Tracy, C. Edwin (Golden, CO)

1998-01-01T23:59:59.000Z

138

Solid lithium-ion electrolyte  

DOE Patents (OSTI)

The present invention relates to the composition of a solid lithium-ion electrolyte based on the Li{sub 2}O--CeO{sub 2}--SiO{sub 2} system having good transparent characteristics and high ion conductivity suitable for uses in lithium batteries, electrochromic devices and other electrochemical applications. 12 figs.

Zhang, J.G.; Benson, D.K.; Tracy, C.E.

1998-02-10T23:59:59.000Z

139

Solid-polymer-electrolyte fuel cells  

DOE Green Energy (OSTI)

A transport model for polymer electrolytes is presented, based on concentrated solution theory and irreversible thermodynamics. Thermodynamic driving forces are developed, transport properties are identified and experiments devised. Transport number of water in Nafion 117 membrane is determined using a concentration cell. It is 1.4 for a membrane equilibrated with saturated water vapor at 25{degrees}C, decreases slowly as the membrane is dehydrated, and falls sharply toward zero as the water content approaches zero. The relation between transference number, transport number, and electroosmotic drag coefficient is presented, and their relevance to water-management is discussed. A mathematical model of transport in a solid-polymer-electrolyte fuel cell is presented. A two-dimensional membrane-electrode assembly is considered. Water management, thermal management, and utilization of fuel are examined in detail. The membrane separators of these fuel cells require sorbed water to maintain conductivity; therefore it is necessary to manage the water content in membranes to ensure efficient operation. Water and thermal management are interrelated. Rate of heat removal is shown to be a critical parameter in the operation of these fuel cells. Current-voltage curves are presented for operation on air and reformed methanol. Equations for convective diffusion to a rotating disk are solved numerically for a consolute point between the bulk concentration and the surface. A singular-perturbation expansion is presented for the condition where the bulk concentration is nearly equal to the consolute-point composition. Results are compared to Levich's solution and analysis.

Fuller, T.F.

1992-07-01T23:59:59.000Z

140

High-Temperature Thermodynamic Data for Species in Aqueous Solution  

Science Conference Proceedings (OSTI)

This report summarizes the results of experimental and theoretical research on the high-temperature thermodynamic properties of aqueous species important to nuclear reactor water chemistry. Methods of predicting thermodynamic functions are presented for electrolytes up to 300 degrees Celsius for use in supplementing experimental data. The report includes tables (up to 300 degrees Celsius) of (1) important equilibrium constants for 78 reactions encountered in corrosion and precipitation in nuclear reactor...

1982-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "aqueous electrolyte modeling" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Non-aqueous solution preparation of doped and undoped lixmnyoz  

DOE Patents (OSTI)

A method for generation of phase-pure doped and undoped Li.sub.x Mn.sub.y O.sub.z precursors. The method of this invention uses organic solutions instead of aqueous solutions or nonsolution ball milling of dry powders to produce phase-pure precursors. These precursors can be used as cathodes for lithium-polymer electrolyte batteries. Dopants may be homogeneously incorporated to alter the characteristics of the powder.

Boyle, Timothy J. (5801 Eubank, N.E., Apt. #97, Albuquerque, NM 87111); Voigt, James A. (187 Aaramar La., Corrales, NM 87048)

1997-01-01T23:59:59.000Z

142

Fuel cell with electrolyte feed system  

DOE Patents (OSTI)

A fuel cell having a pair of electrodes at the sites of electrochemical reactions of hydrogen and oxygen and a phosphoric acid electrolyte provided with an electrolyte supporting structure in the form of a laminated matrix assembly disposed between the electrodes. The matrix assembly is formed of a central layer disposed between two outer layers, each being permeable to the flow of the electrolyte. The central layer is provided with relatively large pores while the outer layers are provided with relatively small pores. An external reservoir supplies electrolyte via a feed means to the central layer to compensate for changes in electrolyte volume in the matrix assembly during the operation of fuel cell.

Feigenbaum, Haim (Highland Park, NJ)

1984-01-01T23:59:59.000Z

143

Polymeric electrolytes for ambient temperature lithium batteries  

DOE Green Energy (OSTI)

A new type of highly conductive Li{sup +} polymer electrolyte, referred to as the Innovision polymer electrolyte, is completely amorphous at room temperature and has an ionic conductivity in the range of 10{sup {minus}3} S/cm. This report discusses the electrochemical characteristics (lithium oxidation and reduction), conductivity, and physical properties of Innovision electrolytes containing various dissolved salts. These electrolytes are particularly interesting since they appear to have some of the highest room-temperature lithium ion conductivities yet observed among polymer electrolytes. 13 refs. 11 figs., 2 tabs.

Farrington, G.C. (Pennsylvania Univ., Philadelphia, PA (United States). Dept. of Materials Science and Engineering)

1991-07-01T23:59:59.000Z

144

Polarization Behavior of Water in Extreme Aqueous Environments: A molecular dynamics study based on the Gaussian Charge Polarizable Water Model.  

Science Conference Proceedings (OSTI)

We study the polarization behavior of water under geologically-relevant extreme aqueous environments along four equidistant supercritical isotherms, 773 ! T (K) ! 1373, and over a wide pressure range, 0 order parameters and the magnitude of the average induced dipole moment of water. The predicted behavior indicates an isothermal linear dependence (a) between the magnitude of the average induced dipole moment ind and the average system density ! , (b) between the magnitude of the average induced dipole ind and that of the total dipole tot , resulting from (c) a compensating (inverse) dependence between the permanent-to-induced dipolar angle ! and the magnitude of the average induced dipole moment ind . Moreover, we interpret this behavior in terms of the evolution of the state dependent tetrahedral order parameter qT and the corresponding bond-order parameter Q6 , supplemented by the microstructural analysis based on the three site-site radial distribution functions of water and the distance-ranked nearest-neighbors distributions. Finally, we show that while water exhibits a dramatic microstructural transformation from an open four-coordinated hydrogen-bonded network at normal conditions to a quasi close-packed coordination, it still preserves a significant degree of hydrogen bonding.

Chialvo, Ariel A [ORNL; Horita, Juske [ORNL

2010-01-01T23:59:59.000Z

145

Novel concepts in electrochemical solar cells. First quarterly progress report, May 15-July 15, 1979. [Molten salt electrolytes  

DOE Green Energy (OSTI)

Emphasis has been directed toward the development and evaluation of an efficient, operational photoelectrochemical cell (PEC) system involving (i) molten salt (and/or highly concentrated, inorganic, non-aqueous) electrolytes, and (ii) the promising semiconductor electrode materials such as CuTnS/sub 2/, CuInSe/sub 2/, MoS/sub 2/, MoSe/sup 2/ etc. As a direct consequence, the stages of the work program that are most critical at this time are the electrode fabrication and characterization and the electrolyte preparation and characterization phases. It has been demonstrated for the first time that a semiconductor electrode exhibits quite large photoeffects in a cell containing a molten salt electrolyte. Detailed studies are underway to explore the constraints and advantages of this type of electrolyte, from the standpoint of efficiency, corrosion of the electrode, and the chemical and physical properties related to overall cell performance. Progress is reported. (WHK)

DuBow, J.

1979-01-01T23:59:59.000Z

146

Composite electrode/electrolyte structure  

DOE Patents (OSTI)

Provided is an electrode fabricated from highly electronically conductive materials such as metals, metal alloys, or electronically conductive ceramics. The electronic conductivity of the electrode substrate is maximized. Onto this electrode in the green state, a green ionic (e.g., electrolyte) film is deposited and the assembly is co-fired at a temperature suitable to fully densify the film while the substrate retains porosity. Subsequently, a catalytic material is added to the electrode structure by infiltration of a metal salt and subsequent low temperature firing. The invention allows for an electrode with high electronic conductivity and sufficient catalytic activity to achieve high power density in ionic (electrochemical) devices such as fuel cells and electrolytic gas separation systems.

Visco, Steven J. (Berkeley, CA); Jacobson, Craig P. (El Cerrito, CA); DeJonghe, Lutgard C. (Lafayette, CA)

2004-01-27T23:59:59.000Z

147

Perovskite solid electrolytes for SOFC  

DOE Green Energy (OSTI)

Selected perovskite solid electrolytes incorporated into research size fuel cells have shown stability for > 4000 hours at 600{degrees}C. Perovskite lattice requirements which favor low E{sub a} for ionic conduction include (i) that the perovskite lattice possess a moderate enthalpy of formation, (ii) perovskite lattice possess large free volumes, (iii) that the lattice minimally polarizes the mobile ion and (iv) that the crystallographic saddle point r{sub c} for ionic conduction is {approx_equal} 1.

Sammells, A.F.

1992-09-01T23:59:59.000Z

148

Incorporation of aqueous reaction kinetics and biodegradation intoTOUGHREACT: Application of a multi-region model to hydrobiogeoChemicaltransport of denitrification and sulfate reduction  

SciTech Connect

The need to consider aqueous and sorption kinetics andmicrobiological processes arises in many subsurface problems. Ageneral-rate expression has been implemented into the TOUGHREACTsimulator, which considers multiple mechanisms (pathways) and includesmultiple product, Monod, and inhibition terms. This paper presents aformulation for incorporating kinetic rates among primary species intomass-balance equations. The space discretization used is based on aflexible integral finite difference approach that uses irregular griddingto model bio-geologic structures. A general multi-region model forhydrological transport interacted with microbiological and geochemicalprocesses is proposed. A 1-D reactive transport problem with kineticbiodegradation and sorption was used to test the enhanced simulator,which involves the processes that occur when a pulse of water containingNTA (nitrylotriacetate) and cobalt is injected into a column. The currentsimulation results agree very well with those obtained with othersimulators. The applicability of this general multi-region model wasvalidated by results from a published column experiment ofdenitrification and sulfate reduction. The matches with measured nitrateand sulfate concentrations were adjusted with the interficial areabetween mobile hydrological and immobile biological regions. Resultssuggest that TOUGHREACT can not only be a useful interpretative tool forbiogeochemical experiments, but also can produce insight into processesand parameters of microscopic diffusion and their interplay withbiogeochemical reactions. The geometric- and process-based multi-regionmodel may provide a framework for understanding field-scalehydrobiogeochemical heterogeneities and upscaling parameters.

Xu, Tianfu

2006-07-13T23:59:59.000Z

149

The H2O2+OH ? HO2+H2O reaction in aqueous solution from a charge-dependent continuum model of solvation  

Science Conference Proceedings (OSTI)

We applied our recently developed protocol of the conductor-like continuum model of solvation to describe the title reaction in aqueous solution. The model has the unique feature of the molecular cavity being dependent on the atomic charges in the solute, and can be extended naturally to transition states and reaction pathways. It was used to calculate the reaction energetics and reaction rate in solution for the title reaction. The rate of reaction calculated using canonical variational transition state theory CVT in the context of the equilibrium solvation path (ESP) approximation, and including correction for tunneling through the small curvature approximation (SCT) was found to be 3.6 106 M-1 s-1, in very good agreement with experiment, These results suggest that the present protocol of the conductor-like continuum model of solvation with the charge-dependent cavity definition captures accurately the solvation effects at transition states and allows for quantitative estimates of reaction rates in solutions. This work was supported by the U.S. Department of Energy's (DOE) Office of Basic Energy Sciences, Chemical Sciences program. The Pacific Northwest National Laboratory is operated by Battelle for DOE.

Ginovska, Bojana; Camaioni, Donald M.; Dupuis, Michel

2008-07-07T23:59:59.000Z

150

Geothermal-brine modeling - prediction of mineral solubilities in natural waters: the Na-K-Mg-Ca-H-Cl-SO{sub 4}-OH-HCO{sub 3} CO{sub 3}-CO{sub 2}-H{sub 2}O system to high ionic strengths at 25{sup 0}C  

DOE Green Energy (OSTI)

The mineral solubility model of Harvie and Weare (1980) is extended to the eight component system, Na-K-Ca-Mg-H-Cl-SO{sub 4}-OH-HCO{sub 3}-CO{sub 3}-CO{sub 2}-H{sub 2}O at 25{sup 0}C to high concentrations. The model is based on the semi-empirical equations of Pitzer (1973) and co-workers for the thermodynamics of aqueous electrolyte solutions. The model is parameterized using many of the available isopiestic, electromotive force, and solubility data available for many of the subsystems. The predictive abilities of the model are demonstrated by comparison to experimental data in systems more complex than those used in parameterization. The essential features of a chemical model for aqueous electrolyte solutions and the relationship between pH and the equilibrium properties of a solution are discussed.

Weare, J.H.

1981-01-01T23:59:59.000Z

151

Rate-Based Modeling of Reactive Absorption of CO2 and H2S into Aqueous Methyldiethanolamine  

E-Print Network (OSTI)

at Austin, Austin, Texas 78712 A general framework was developed to model the transport processes that take into the mass and energy balance at a given segment or tray of the column for the simulataneous absorption of CO

Rochelle, Gary T.

152

Solid-oxide fuel cell electrolyte  

DOE Patents (OSTI)

This invention is comprised of a solid-oxide electrolyte operable at between 600{degrees}C and 800{degrees}C and a method of producing the solid-oxide electrolyte. The solid-oxide electrolyte comprises a combination of a compound having a weak metal-oxygen interactions with a compound having stronger metal-oxygen interactions whereby the resulting combination has both strong and weak metal-oxygen interaction properties.

Bloom, I.D.; Hash, M.C.; Krumpelt, M.

1991-12-31T23:59:59.000Z

153

Fuel cell assembly with electrolyte transport  

DOE Patents (OSTI)

A fuel cell assembly wherein electrolyte for filling the fuel cell matrix is carried via a transport system comprising a first passage means for conveying electrolyte through a first plate and communicating with a groove in a second plate at a first point, the first and second plates together sandwiching the matrix, and second passage means acting to carry electrolyte exclusively through the second plate and communicating with the groove at a second point exclusive of the first point.

Chi, Chang V. (Brookfield, CT)

1983-01-01T23:59:59.000Z

154

Electrolytic cell. [For separating anolyte and catholyte  

DOE Patents (OSTI)

An apparatus is described for the separation of the anolyte and the catholyte during electrolysis. The electrolyte flows through an electrolytic cell between the oppositely charged electrodes. The cell is equipped with a wedge-shaped device, the tapered end being located between the electrodes on the effluent side of the cell. The wedge diverts the flow of the electrolyte to either side of the wedge, substantially separating the anolyte and the catholyte.

Bullock, J.S.; Hale, B.D.

1984-09-14T23:59:59.000Z

155

EQ6, a computer program for reaction path modeling of aqueous geochemical systems: Theoretical manual, user`s guide, and related documentation (Version 7.0); Part 4  

Science Conference Proceedings (OSTI)

EQ6 is a FORTRAN computer program in the EQ3/6 software package (Wolery, 1979). It calculates reaction paths (chemical evolution) in reacting water-rock and water-rock-waste systems. Speciation in aqueous solution is an integral part of these calculations. EQ6 computes models of titration processes (including fluid mixing), irreversible reaction in closed systems, irreversible reaction in some simple kinds of open systems, and heating or cooling processes, as well as solve ``single-point`` thermodynamic equilibrium problems. A reaction path calculation normally involves a sequence of thermodynamic equilibrium calculations. Chemical evolution is driven by a set of irreversible reactions (i.e., reactions out of equilibrium) and/or changes in temperature and/or pressure. These irreversible reactions usually represent the dissolution or precipitation of minerals or other solids. The code computes the appearance and disappearance of phases in solubility equilibrium with the water. It finds the identities of these phases automatically. The user may specify which potential phases are allowed to form and which are not. There is an option to fix the fugacities of specified gas species, simulating contact with a large external reservoir. Rate laws for irreversible reactions may be either relative rates or actual rates. If any actual rates are used, the calculation has a time frame. Several forms for actual rate laws are programmed into the code. EQ6 is presently able to model both mineral dissolution and growth kinetics.

Wolery, T.J.; Daveler, S.A.

1992-10-09T23:59:59.000Z

156

Implementing Wireless Electrolytic Cell Monitoring System at ...  

Science Conference Proceedings (OSTI)

Based on Kennecott Utah Copper's innovation, Outotec has developed in partnership a novel electrolytic cell monitoring system, CellSenseTM System. As the ...

157

Electrolytic process for preparing uranium metal  

SciTech Connect

An electrolytic process for making uranium from uranium oxide using Cl.sub.2 anode product from an electrolytic cell to react with UO.sub.2 to form uranium chlorides. The chlorides are used in low concentrations in a melt comprising fluorides and chlorides of potassium, sodium and barium in the electrolytic cell. The electrolysis produces Cl.sub.2 at the anode that reacts with UO.sub.2 in the feed reactor to form soluble UCl.sub.4, available for a continuous process in the electrolytic cell, rather than having insoluble UO.sub.2 fouling the cell.

Haas, Paul A. (Knoxville, TN)

1990-01-01T23:59:59.000Z

158

Novel Electrolyte Enables Stable Graphite Anodes in ...  

Berkeley Lab researchers led by Gao Liu have developed an improved lithium ion battery electrolyte containing a solvent that remains liquid at typical ...

159

Environmentally Benign Electrolytes With Wide Electrochemical ...  

Very few electrolytes have been developed thus far that exhibit the above combination of performance ... cells without significant extra cost. ... Cyc ...

160

Block copolymer electrolytes for lithium batteries  

E-Print Network (OSTI)

Ethylene Carbonate for Lithium Ion Battery Use. Journal oflithium atoms in lithium-ion battery electrolyte. Chemicalcapacity fading of a lithium-ion battery cycled at elevated

Hudson, William Rodgers

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "aqueous electrolyte modeling" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Electrochemical cell with high conductivity glass electrolyte  

DOE Patents (OSTI)

A secondary electrochemical cell with sodium-sulfur or other molten reactants is provided with a ionically conductive glass electrolyte. The cell is contained within an electrically conductive housing with a first portion at negative potential and a second portion insulated therefrom at positive electrode potential. The glass electrolyte is formed into a plurality of elongated tubes and placed lengthwise within the housing. The positive electrode material, for instance sulfur, is sealed into the glass electrolyte tubes and is provided with an elongated axial current collector. The glass electrolyte tubes are protected by shield tubes or sheets that also define narrow annuli for wicking of the molten negative electrode material. 6 figs.

Nelson, P.A.; Bloom, I.D.; Roche, M.F.

1987-04-21T23:59:59.000Z

162

Electrochemical cell with high conductivity glass electrolyte  

DOE Patents (OSTI)

A secondary electrochemical cell with sodium-sulfur or other molten reactants is provided with an ionically conductive glass electrolyte. The cell is contained within an electrically conductive housing with a first portion at negative potential and a second portion insulated therefrom at positive electrode potential. The glass electrolyte is formed into a plurality of elongated tubes and placed lengthwise within the housing. The positive electrode material, for instance sulfur, is sealed into the glass electrolyte tubes and is provided with an elongated axial current collector. The glass electrolyte tubes are protected by shield tubes or sheets that also define narrow annuli for wicking of the molten negative electrode material.

Nelson, P.A.; Bloom, I.D.; Roche, M.F.

1986-04-17T23:59:59.000Z

163

Nanopower: Avoiding Electrolyte Failure in Nanoscale Lithium ...  

Science Conference Proceedings (OSTI)

... most of which is the battery itself—which ... wide—solid-state lithium ion batteries to see just ... cathode material, electrolyte, and anode materials with ...

2012-04-11T23:59:59.000Z

164

The Market Potential for Electrolytic Hydrogen  

Science Conference Proceedings (OSTI)

Analyzes the small-user hydrogen market. Improvements in current electrolyzer technology may make electrolytic hydrogen competitive with purchased (merchant) hydrogen for many specialty users.

1979-08-01T23:59:59.000Z

165

Electrolytic cells for hydrogen gas production  

SciTech Connect

An electrolytic cell bank is described comprising two end plate electrodes, a plurality of intermediate electrodes, a plurality of dielectric separators spaced between the electrodes to form electrolytic cell chambers, a plurality of gas separator diaphragms, alkaline electrolyte, manifolds for allowing off-gas withdrawal of hydrogen and oxygen and means for back-pressuring the exterior walls of each end plate to counter-balance pressures developed within the electrolytic cell chambers. The cell bank is utilized to convert water into its constituent gases of oxygen and hydrogen, and the cell bank is sufficiently large to commercially produce hydrogen at pressures equal to the pressures utilized in commercial gas transmission lines.

Hall, F.F.

1980-11-25T23:59:59.000Z

166

Solid-polymer-electrolyte fuel cells  

DOE Green Energy (OSTI)

A transport model for polymer electrolytes is presented, based on concentrated solution theory and irreversible thermodynamics. Thermodynamic driving forces are developed, transport properties are identified and experiments devised. Transport number of water in Nafion 117 membrane is determined using a concentration cell. It is 1.4 for a membrane equilibrated with saturated water vapor at 25{degrees}C, decreases slowly as the membrane is dehydrated, and falls sharply toward zero as the water content approaches zero. The relation between transference number, transport number, and electroosmotic drag coefficient is presented, and their relevance to water-management is discussed. A mathematical model of transport in a solid-polymer-electrolyte fuel cell is presented. A two-dimensional membrane-electrode assembly is considered. Water management, thermal management, and utilization of fuel are examined in detail. The membrane separators of these fuel cells require sorbed water to maintain conductivity; therefore it is necessary to manage the water content in membranes to ensure efficient operation. Water and thermal management are interrelated. Rate of heat removal is shown to be a critical parameter in the operation of these fuel cells. Current-voltage curves are presented for operation on air and reformed methanol. Equations for convective diffusion to a rotating disk are solved numerically for a consolute point between the bulk concentration and the surface. A singular-perturbation expansion is presented for the condition where the bulk concentration is nearly equal to the consolute-point composition. Results are compared to Levich`s solution and analysis.

Fuller, T.F.

1992-07-01T23:59:59.000Z

167

Dynamic modeling to minimize energy use for CO{sub 2} capture in power plants by aqueous monoethanolamine  

SciTech Connect

A dynamic rate-based model was developed for stripping in CO{sub 2} capture from coal-fired power plants with 30 wt% monoethanolamine (MEA). The model, created in a flow sheet of Aspen Custom Modeler, was based on the film theory for liquid and vapor phases. It takes into account the impact of equilibrium reactions on the mass transfer, thermodynamic nonidealities, and the hydraulics of the structured packing. With this model, steady state analyses were. carried out for the stripper to understand the effect of the leah loading and the height of the packing on total equivalent work and find optimum operating conditions that minimize power plant lost work. Two dynamic strategies with control configurations are proposed to run the stripper in a flexible operation during the period of electricity peak load and prices. Open loop responses demonstrated some differences in dynamic behavior and steady state values for proposed dynamic strategies. One of the approaches increased the CO{sub 2} removal by 1% at the reduced steam rate and provided faster response of the stripper to a step change in the reboiler heat rate.

Ziaii, S.; Rochelle, G.T.; Edgar, T.F. [University of Texas Austin, Austin, TX (United States). Dept. of Chemical Engineering

2009-07-15T23:59:59.000Z

168

Gel electrolyte for lithium-ion batteries.  

DOE Green Energy (OSTI)

The electrochemical performance of gel electrolytes based on crosslinked poly[ethyleneoxide-co-2-(2-methoxyethyoxy)ethyl glycidyl ether-co-allyl glycidyl ether] was investigated using graphite/Li{sub 1.1}[Ni{sub 1/3}Mn{sub 1/3}Co{sub 1/3}]{sub 0.9}O{sub 2} lithium-ion cells. It was found that the conductivity of the crosslinked gel electrolytes was as high as 5.9 mS/cm at room temperature, which is very similar to that of the conventional organic carbonate liquid electrolytes. Moreover, the capacity retention of lithium-ion cells comprising gel electrolytes was also similar to that of cells with conventional electrolytes. Despite of the high conductivity of the gel electrolytes, the rate capability of lithium-ion cells comprising gel electrolytes is inferior to that of the conventional cells. The difference was believed to be caused by the poor wettability of gel electrolytes on the electrode surfaces.

Chen, Z.; Zhang, L. Z.; West, R.; Amine, K.; Chemical Sciences and Engineering Division; Univ. of Wisconsin-Madison

2008-03-10T23:59:59.000Z

169

Solid composite electrolytes for lithium batteries  

DOE Patents (OSTI)

Solid composite electrolytes are provided for use in lithium batteries which exhibit moderate to high ionic conductivity at ambient temperatures and low activation energies. In one embodiment, a ceramic-ceramic composite electrolyte is provided containing lithium nitride and lithium phosphate. The ceramic-ceramic composite is also preferably annealed and exhibits an activation energy of about 0.1 eV.

Kumar, Binod (Dayton, OH); Scanlon, Jr., Lawrence G. (Fairborn, OH)

2000-01-01T23:59:59.000Z

170

Process of making electrolyte structure for molten carbonate fuel cells  

DOE Patents (OSTI)

An electrolyte structure is produced by forming matrix material powder into a blank at room temperature and impregnating the resulting matrix blank with molten electrolyte.

Arendt, R.H.; Curran, M.J.

1980-08-05T23:59:59.000Z

171

Process of making electrolyte structure for molten carbonate fuel cells  

DOE Patents (OSTI)

An electrolyte structure is produced by forming matrix material powder into a blank at room temperature and impregnating the resulting matrix blank with molten electrolyte.

Arendt, Ronald H. (Schenectady, NY); Curran, Matthew J. (Schenectady, NY)

1980-01-01T23:59:59.000Z

172

Amorphous LLZO sol gel solid electrolyte  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Novel Li Conducting Solid State Novel Li Conducting Solid State Electrolyte by Sol Gel Technique Davorin Babic, Ph. D. Excellatron Solid State LLC 263 Decatur St Atlanta, GA 30312 (404) 584-2475 dbabic@excellatron.com Objective Develop novel inorganic solid state lithium ion conductor: a) high Li ion conductivity b) transport number of ~1 c) stable with Li metal d) thermally stable e) adequate electrochemical window of stability Construct and test a battery that contains the novel electrolyte Novel sol gel solid electrolyte (NSGSE) In contact with Li metal: Organic electrolytes (liquid/polymer) get reduced: HAZARDS Most oxide solid electrolytes become mixed conductor: SHORTS NSGSE by sol gel process, spin coated: an oxide & stable with Li !! -100000 0 100000 200000 300000 400000 -400000

173

Aqueous coal slurry  

DOE Patents (OSTI)

A principal object of the invention is the provision of an aqueous coal slurry containing a dispersant, which is of low-cost and which contains very low or no levels of sodium, potassium, sulfur and other contaminants. In connection with the foregoing object, it is an object of the invention to provide an aqueous slurry containing coal and dextrin as a dispersant and to provide a method of preparing an aqueous coal slurry which includes the step of adding an effective amount of dextrin as a dispersant. The invention consists of certain novel features and a combination of parts hereinafter fully described, and particularly pointed out in the appended claims. 6 tabs.

Berggren, M.H.; Smit, F.J.; Swanson, W.W.

1989-10-30T23:59:59.000Z

174

Dissolution of quartz in lead and sodium electrolyte solutions between 25 and 300[degrees]C: Effect of the nature of surface complexes and reaction affinity  

SciTech Connect

The dissolution rate of quartz has been measured at 25[degrees]C in batch reactors and at 200 and 300[degrees]C in mixed flow reactors. Those experiments have been carried out in both pure H[sub 2]O and solutions containing Na or Pb at various ionic strengths and pH. The measured rates were found to increase significantly with the addition of either Na or Pb. In an attempt to determine the mechanism of these effects, the degree of adsorption of Na and Pb were measured on amorphous silica at 25 and 150[degrees]C. At 25[degrees]C, Na is found to adsorb on the quartz surface as an outer-sphere complex, and the corresponding dissolution rate increase is explained by an increase of the ionic strength. By contrast, at 25[degrees], lead, which forms inner-sphere complexes, increases the quartz dissolution rate specifically. At high temperature, quartz dissolution is promoted in the presence of both Na and Pb by a pH-dependent formation of surface inner-sphere complexes. This effect tends to vanish when the degree of saturation of the solution increases, as a result of the competition between electrolyte and aqueous silica adsorption on quartz surface. These results show that the electrolytes which adsorb as inner-sphere complexes dominate the overall reaction at conditions far from equilibrium only. Consequently, for a large range of chemical affinity quartz dissolution in Na and Pb electrolyte solutions can be modeled within the framework of the Transition State Theory by simply taking into account the protonated surface species and the ionic strength of the solution.

Berger, G.; Cadore, E.; Schott, J. (Laboratoire de Geochimi, Toulouse (France)); Dove, P.M. (Princeton Univ., NJ (United States))

1994-01-01T23:59:59.000Z

175

Electrolyte for an electrochemical cell  

DOE Patents (OSTI)

Described is a thin-film battery, especially a thin-film microbattery, and a method for making the same having application as a backup or primary integrated power source for electronic devices. The battery includes a novel electrolyte amorphous lithium phosphorus oxynitride which is electrochemically stable and does not react with the lithium anode and a novel vanadium oxide cathode Configured as a microbattery, the battery can be fabricated directly onto a semiconductor chip, onto the semiconductor die or onto any portion of the chip carrier. The battery can be fabricated to any specified size or shape to meet the requirements of a particular application. The battery is fabricated of solid state materials and is capable of operation between {minus}15 C and 150 C. 9 figs.

Bates, J.B.; Dudney, N.J.

1997-01-28T23:59:59.000Z

176

Electrolyte for an electrochemical cell  

DOE Patents (OSTI)

Described is a thin-film battery, especially a thin-film microbattery, and a method for making same having application as a backup or primary integrated power source for electronic devices. The battery includes a novel electrolyte amorphous lithium phosphorus oxynitride which is electrochemically stable and does not react with the lithium anode and a novel vanadium oxide cathode Configured as a microbattery, the battery can be fabricated directly onto a semiconductor chip, onto the semiconductor die or onto any portion of the chip carrier. The battery can be fabricated to any specified size or shape to meet the requirements of a particular application. The battery is fabricated of solid state materials and is capable of operation between -15.degree. C. and 150.degree. C.

Bates, John B. (Oak Ridge, TN); Dudney, Nancy J. (Knoxville, TN)

1997-01-01T23:59:59.000Z

177

SYNTHESIS OF A NEW FAMILY OF FLUORINATED BORONATE COMPOUNDS AS ANION RECEPTORS AND STUDIES OF THEIR USE AS ADDITIVES IN LITHIUM BATTERY ELECTROLYTES.  

DOE Green Energy (OSTI)

Numerous studies have been done on developing new electrolytes for lithium batteries with high ionic conductivity, and good chemical and electrochemical stability. In addition to the research on new salts and solvents, the use of cation receptors to reduce ion pairing in non-aqueous electrolytes has been considered as an approach to improve the properties of electrolytes. Although both cation and anion receptors enhance the dissociation of ion pairs and increase the conductivity of electrolytes, the use of anion receptors is more attractive for a lithium battery electrolyte because anion receptors increase the lithium transference number in the electrolyte. However, most available neutral anion receptors complex with anions through hydrogen binding and cannot be used in lithium batteries. Recently, we have reported on synthesis of a series of new neutral boron compounds as anion receptors based on the idea that electron-deficient boron would complex the anion of the ion pair. The anion complexation effect of these boron compounds was further enhanced by attaching electron-withdrawing groups. Here we report synthesis of another new family of boronate compounds. The effect of these new compounds on conductivity of lithium salts in non-aqueous solution was studied. The molecular weights of these new boronate compounds are lower than our previously reported boron compounds. Therefore, their effects on conductivity enhancement are superior. They also display high electrochemical stability up to 5 V.

MCBREEN,J.; LEE,H.S.; YANG,X.Q.

2001-06-08T23:59:59.000Z

178

Aqueous coal slurry  

DOE Patents (OSTI)

An aqueous slurry containing coal and dextrin as a dispersant. The slurry, in addition to containing dextrin, may contain a conventional dispersant or, alternatively, a pH controlling reagent.

Berggren, Mark H. (Golden, CO); Smit, Francis J. (Arvada, CO); Swanson, Wilbur W. (Golden, CO)

1993-01-01T23:59:59.000Z

179

Towards standardizing the measurement of electrochemical properties of solid state electrolytes in lithium batteries.  

DOE Green Energy (OSTI)

The purpose of this paper is to stimulate thought and discussion in the technical community on standardization of the experimental determination of the pertinent electrochemical properties of solid electrolytes in lithium batteries. This standardization is needed for comparison and modeling of solid electrolytes in a practical lithium battery. The appropriate electrochemical properties include transport, thermodynamic, and physical parameters that generally depend on concentration and temperature. While it is beyond the scope of this work to put forward definitive measurement techniques for all types of solid electrolytes, it is hoped that comparisons between various techniques to examine a dissolved binary lithium salt in a dry polymer solvent will lead to improved understanding and methodology for examining solid electrolytes.

Dees, D. W.; Henriksen, G. L.

1999-05-06T23:59:59.000Z

180

Washer with electrolytic water dissociation. Final report  

SciTech Connect

The development of a washing machine with turbo-electrolytic pre-wash facility is described. This process involves a preliminary electro-chemical process which is characterized by an overall reduction in energy consumption during the wash cycle. Comparative studies between the turbo-electrolytic washing machine and a standard washing machine have been carried out. Although the production cost of the turbo-electrolytic machine is greater, savings on energy costs will give rise to a net reduction in costs over the lifetime of the machine.

Morello, M.

1984-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "aqueous electrolyte modeling" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Intermediate Temperature SOFC Operation Using Lanthanum Gallate Electrolyte  

DOE Green Energy (OSTI)

This presentation discusses intermediate temperature SOFC operation using lanthanum gallate electrolyte.

Elangovan, S.; Balagopal, S. Hartvigsen, J.; Tipmer, M.; Larsen, D.

2005-01-27T23:59:59.000Z

182

Macroscopic Modeling of Polymer-Electrolyte Membranes  

E-Print Network (OSTI)

Fuel Cells Iv, The Electrochemical Society Proceeding Series, Pennington, NJ,Fuel Cells, PV 95-23, The Electrochemical Society Proceeding Series, Pennington, NJ,Fuel Cell, and Photoenergy Conversion Systems, PV 86-12, The Electrochemical Society Proceeding Series, Pennington, Nj,

Weber, A.Z.; Newman, J.

2008-01-01T23:59:59.000Z

183

Electrolytic Infiltration into Laser Sintered Porous Graphite  

Science Conference Proceedings (OSTI)

Symposium, Green Technologies for Materials Manufacturing and Processing V. Presentation Title, Electrolytic Infiltration into Laser Sintered Porous Graphite ... Tensile and Fatigue Testing of 304 Stainless Steel after Gaseous Hydrogen ...

184

Photo-electrolytic production of hydrogen  

SciTech Connect

Hydrogen and oxygen are produced from water in a process involving the photodissociation of molecular bromine with radiant energy at wavelengths within the visible light region and a subsequent electrolytic dissociation of hydrogen halides.

Meyerand, R.G. Jr.; Krascella, N.L.; McMahon, D.G.

1978-01-17T23:59:59.000Z

185

A disposable, self-administered electrolyte test  

E-Print Network (OSTI)

This thesis demonstrates the novel concept that it is possible to make a disposable, self-administered electrolyte test to be introduced to the general consumer market. Although ion specific electrodes have been used to ...

Prince, Ryan, 1977-

2003-01-01T23:59:59.000Z

186

Fuel cell electrolyte membrane with acidic polymer  

DOE Patents (OSTI)

An electrolyte membrane is formed by an acidic polymer and a low-volatility acid that is fluorinated, substantially free of basic groups, and is either oligomeric or non-polymeric.

Hamrock, Steven J. (Stillwater, MN); Larson, James M. (Saint Paul, MN); Pham, Phat T. (Little Canada, MN); Frey, Matthew H. (Cottage Grove, MN); Haugen, Gregory M. (Edina, MN); Lamanna, William M. (Stillwater, MN)

2009-04-14T23:59:59.000Z

187

Fuel cell with electrolyte matrix assembly  

DOE Patents (OSTI)

This invention is directed to a fuel cell employing a substantially immobilized electrolyte imbedded therein and having a laminated matrix assembly disposed between the electrodes of the cell for holding and distributing the electrolyte. The matrix assembly comprises a non-conducting fibrous material such as silicon carbide whiskers having a relatively large void-fraction and a layer of material having a relatively small void-fraction.

Kaufman, Arthur (West Orange, NJ); Pudick, Sheldon (Sayreville, NJ); Wang, Chiu L. (Edison, NJ)

1988-01-01T23:59:59.000Z

188

Nonaqueous electrolyte for electrical storage devices  

DOE Patents (OSTI)

Improved nonaqueous electrolytes for application in electrical storage devices such as electrochemical capacitors or batteries are disclosed. The electrolytes of the invention contain salts consisting of alkyl substituted, cyclic delocalized aromatic cations, and their perfluoro derivatives, and certain polyatomic anions having a van der Waals volume less than or equal to 100 .ANG..sup.3, preferably inorganic perfluoride anions and most preferably PF.sub.6.sup.-, the salts being dissolved in organic liquids, and preferably alkyl carbonate solvents, or liquid sulfur dioxide or combinations thereof, at a concentration of greater than 0.5M and preferably greater than 1.0M. Exemplary electrolytes comprise 1-ethyl-3-methylimidazolium hexafluorophosphate dissolved in a cyclic or acylic alkyl carbonate, or methyl formate, or a combination therof. These improved electrolytes have useful characteristics such as higher conductivity, higher concentration, higher energy storage capabilities, and higher power characteristics compared to prior art electrolytes. Stacked capacitor cells using electrolytes of the invention permit high energy, high voltage storage.

McEwen, Alan B. (Melrose, MA); Yair, Ein-Eli (Waltham, MA)

1999-01-01T23:59:59.000Z

189

Electrolytic recovery of reactor metal fuel  

DOE Patents (OSTI)

A new electrolytic process and apparatus are provided using sodium, cerium or a similar metal in alloy or within a sodium beta or beta[double prime]-alumina sodium ion conductor to electrolytically displace each of the spent fuel metals except for cesium and strontium on a selective basis from the electrolyte to an inert metal cathode. Each of the metals can be deposited separately. An electrolytic transfer of spent fuel into the electrolyte includes a sodium or cerium salt in the electrolyte with sodium or cerium alloy being deposited on the cathode during the transfer of the metals from the spent fuel. The cathode with the deposit of sodium or cerium alloy is then shunted to an anode and the reverse transfer is carried out on a selective basis with each metal being deposited separately at the cathode. The result is that the sodium or cerium needed for the process is regenerated in the first step and no additional source of these reactants is required. 2 figs.

Miller, W.E.; Tomczuk, Z.

1994-09-20T23:59:59.000Z

190

LOW TEMPERATURE CATHODE SUPPORTED ELECTROLYTES  

DOE Green Energy (OSTI)

This report represents a summary of the work carried out on this project which started October 1999 and ended March 2003. A list of the publications resulting from the work are contained in Appendix A. The most significant achievements are: (1) Dense nanocrystalline zirconia and ceria films were obtained at temperatures < 400 C. (2) Nanocrystalline films of both ceria and zirconia were characterized. (3) We showed that under anodic conditions 0.5 to 1 micron thick nanocrystalline films of Sc doped zirconia have sufficient electronic conductivity to prevent them from being useful as an electrolyte. (4) We have developed a process by which dense 0.5 to 5 micron thick dense films of either YSZ or ceria can be deposited on sintered porous substrates which serve as either the cathode or anode at temperatures as low as 400 C. (5) The program has provided the research to produce two PhD thesis for students, one is now working in the solid oxide fuel cell field. (6) The results of the research have resulted in 69 papers published, 3 papers submitted or being prepared for publication, 50 oral presentations and 3 patent disclosures.

Harlan U. Anderson; Fatih Dogan; Vladimir Petrovsky

2003-03-31T23:59:59.000Z

191

Electrolytic production of uranous nitrate  

SciTech Connect

Efficient production of uranous nitrate is important in nuclear fuel reprocessing because U(IV) acts as a plutonium reductant in solvent extraction and can be coprecipitated with plutonium and/or throium as oxalates during fuel reprocessing. Experimental conditions are described for the efficient electrolytic production of uranous nitrate for use as a reductant in the SRP Purex process. The bench-scale, continuous-flow, electrolysis cell exhibits a current efficiency approaching 100% in combination with high conversion rates of U(VI) to U(IV) in simulated and actual SRP Purex solutions. High current efficiency is achieved with a voltage-controlled mercury-plated platinum electrode and the use of hydrazine as a nitrite scavenger. Conversion of U(VI) to U(IV) proceeds at 100% efficiency. Cathodic gas generation is minimal. The low rate of gas generation permits a long residence time within the cathode, a necessary condition for high conversions on a continuous basis. Design proposals are given for a plant-scale, continuous-flow unit to meet SRP production requirements. Results from the bench-scale tests indicate that an 8-kW unit can supply sufficient uranous nitrate reductant to meet the needs of the Purex process at SRP.

Orebaugh, E.G.; Propst, R.C.

1980-04-01T23:59:59.000Z

192

Continuous aqueous tritium monitor  

DOE Patents (OSTI)

An apparatus for a selective on-line determination of aqueous tritium concentration is disclosed. A moist air stream of the liquid solution being analyzed is passed through a permeation dryer where the tritium and moisture and selectively removed to a purge air stream. The purge air stream is then analyzed for tritium concentration, humidity, and temperature, which allows computation of liquid tritium concentration.

McManus, Gary J. (Idaho Falls, ID); Weesner, Forrest J. (Idaho Falls, ID)

1989-05-30T23:59:59.000Z

193

Suppressant:Water & Aqueous Solutions  

Science Conference Proceedings (OSTI)

Suppressant:Water & Aqueous Solutions. ... Reuther, JJ; 1991. Fine Water Sprays for Fire Protection: A Halon Replacement Option.. ...

2011-10-28T23:59:59.000Z

194

Combination for electrolytic reduction of alumina  

DOE Patents (OSTI)

An electrolytic bath for use during the electrolytic reduction of alumina to aluminum. The bath comprises molten electrolyte having the following ingredients: AlF.sub.3 and at least one salt selected from the group consisting of NaF, KF, and LiF; and about 0.004 wt. % to about 0.2 wt. %, based on total weight of the molten electrolyte, of at least one transition metal or at least one compound of the metal or both. The compound is, a fluoride; oxide, or carbonate. The metal is nickel, iron, copper, cobalt, or molybdenum. The bath is employed in a combination including a vessel for containing the bath and at least one non-consumable anode and at least one dimensionally stable cathode in the bath. Employing the instant bath during electrolytic reduction of alumina to aluminum improves the wetting of aluminum on a cathode by reducing or eliminating the formation of non-metallic deposits on the cathode.

Brown, Craig W. (Seattle, WA); Brooks, Richard J. (Seattle, WA); Frizzle, Patrick B. (Lynnwood, WA); Juric, Drago D. (Bulleen, AU)

2002-04-30T23:59:59.000Z

195

Electrolytic Cell For Production Of Aluminum Employing Planar Anodes.  

SciTech Connect

A method of producing aluminum in an electrolytic cell containing alumina dissolved in an electrolyte, the method comprising providing a molten salt electrolyte having alumina dissolved therein in an electrolytic cell. A plurality of anodes and cathodes having planar surfaces are disposed in a generally vertical orientation in the electrolyte, the anodes and cathodes arranged in alternating or interleaving relationship to provide anode planar surfaces disposed opposite cathode planar surfaces, the anode comprised of carbon. Electric current is passed through anodes and through the electrolyte to the cathodes depositing aluminum at the cathodes and forming carbon containing gas at the anodes.

Barnett, Robert J. (Goldendale, WA); Mezner, Michael B. (Sandy, OR); Bradford, Donald R (Underwood, WA)

2004-10-05T23:59:59.000Z

196

Recovery of mercury from mercury compounds via electrolytic methods  

DOE Patents (OSTI)

A process for electrolytically recovering mercury from mercury compounds is provided. In one embodiment, Hg is recovered from Hg.sub.2 Cl.sub.2 employing as the electrolyte solution a mixture of HCl and H.sub.2 O. In another embodiment, Hg is electrolytically recovered from HgO wherein the electrolyte solution is comprised of glacial acetic acid and H.sub.2 O. Also provided is an apparatus for producing isotopically enriched mercury compounds in a reactor and then transporting the dissolved compounds into an electrolytic cell where mercury ions are electrolytically reduced and elemental mercury recovered from the mercury compounds.

Grossman, Mark W. (Belmont, MA); George, William A. (Rockport, MA)

1988-01-01T23:59:59.000Z

197

Recovery of mercury from mercury compounds via electrolytic methods  

DOE Patents (OSTI)

A process for electrolytically recovering mercury from mercury compounds is provided. In one embodiment, Hg is recovered from Hg[sub 2]Cl[sub 2] employing as the electrolyte solution a mixture of HCl and H[sub 2]O. In another embodiment, Hg is electrolytically recovered from HgO wherein the electrolyte solution is comprised of glacial acetic acid and H[sub 2]O. Also provided is an apparatus for producing isotopically enriched mercury compounds in a reactor and then transporting the dissolved compounds into an electrolytic cell where mercury ions are electrolytically reduced and elemental mercury recovered from the mercury compounds. 3 figs.

Grossman, M.W.; George, W.A.

1989-11-07T23:59:59.000Z

198

Recovery of mercury from mercury compounds via electrolytic methods  

DOE Patents (OSTI)

A process for electrolytically recovering mercury from mercury compounds is provided. In one embodiment, Hg is recovered from Hg.sub.2 Cl.sub.2 employing as the electrolyte solution a mixture of HCl and H.sub.2 O. In another embodiment, Hg is electrolytically recovered from HgO wherein the electrolyte solution is comprised of glacial acetic acid and H.sub.2 O. Also provided is an apparatus for producing isotopically enriched mercury compounds in a reactor and then transporting the dissolved compounds into an electrolytic cell where mercury ions are electrolytically reduced and elemental mercury recovered from the mercury compounds.

Grossman, Mark W. (Belmont, MA); George, William A. (Rockport, MA)

1989-01-01T23:59:59.000Z

199

Recovery of mercury from mercury compounds via electrolytic methods  

DOE Patents (OSTI)

A process for electrolytically recovering mercury from mercury compounds is provided. In one embodiment, Hg is recovered from Hg.sub.2 Cl.sub.2 employing as the electrolyte solution a mixture of HCl and H.sub.2 O. In another embodiment, Hg is electrolytically recovered from HgO wherein the electrolyte solution is comprised of glacial acetic acid and H.sub.2 O. Also provided is an apparatus for producing isotopically enriched mercury compounds in a reactor and then transporting the dissolved compounds into an electrolytic cell where mercury ions are electrolytically reduced and elemental mercury recovered from the mercury compounds.

Grossman, Mark W. (Belmont, MA); George, William A. (Rockport, MA)

1991-01-01T23:59:59.000Z

200

Recovery of mercury from mercury compounds via electrolytic methods  

DOE Patents (OSTI)

A process for electrolytically recovering mercury from mercury compounds is provided. In one embodiment, Hg is recovered from Hg[sub 2]Cl[sub 2] employing as the electrolyte solution a mixture of HCl and H[sub 2]O. In another embodiment, Hg is electrolytically recovered from HgO wherein the electrolyte solution is comprised of glacial acetic acid and H[sub 2]O. Also provided is an apparatus for producing isotopically enriched mercury compounds in a reactor and then transporting the dissolved compounds into an electrolytic cell where mercury ions are electrolytically reduced and elemental mercury recovered from the mercury compounds. 3 figures.

Grossman, M.W.; George, W.A.

1991-06-18T23:59:59.000Z

Note: This page contains sample records for the topic "aqueous electrolyte modeling" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Solid electrolytes strengthened by metal dispersions  

DOE Patents (OSTI)

An improvement in solid electrolytes of advanced secondary batteries of the sodium-sulfur, sodium-halogen, and like combinations is achieved by providing said battery with a cermet electrolyte containing a metal dispersion ranging from 0.1 to 10.0 vol. % of a substantially nonreactive metal selected from the group consisting essentially of Pt, Cr, Fe, Co, Ni, Nb, their alloys, and their physical mixtures in the elemental or uncombined state, the remainder of said cermet being an ion-conductive ceramic material.

Lauf, R.J.; Morgan, C.S.

1981-10-05T23:59:59.000Z

202

Solid electrolytes for medium temperature steam electrolysis  

SciTech Connect

A research program has been initiated to screen and select electrolyte materials for use in steam electrolyzers in the 300 to 600/sup 0/C temperature range. Screening of a significant number of acid anhydrides, hydroxides, oxides, and phosphates for their electrolytic conductivity properties is underway. Of the binary materials examined to date, only polymerized phosphoric acid, immobilized on an H/sup +/ substituted zeolite, shows promise. A substantial number of ternary compounds remain to be synthesized and evaluated. 7 references, 4 figures, 4 tables.

Findl, E.; Kulesa, F.; Montoneri, E.

1984-04-01T23:59:59.000Z

203

Cathode for electrolytic production of hydrogen  

SciTech Connect

A cathode for use in the electrochemical production of hydrogen and a process for making it which involves direct electrochemical cathodic action on a thermally produced adherent oxide on a nickel cathode surface are disclosed. Examples include a nickel sheet thermally oxidized in air at 600/sup 0/ C. for one hour and used directly in the production of electrolytic hydrogen and an iron sheet plasma sprayed with nickel to provide a surface containing thermal oxidation product of nickel and again used directly in the electrolytic production of hydrogen.

Hall, D.E.

1983-10-18T23:59:59.000Z

204

Solid electrolyte battery materials. Technical report  

SciTech Connect

This is the third technical report relating to work on Solid Electrolyte Battery Materials. During the past 18 months our efforts have had two major aims: one is to develop a novel technique for producing beta alumina solid electrolytes for use in the sodium-sulfur cell. The other is to search for new fast ion conducting materials for lithium and potassium ions, as well as to examine mixed conductor materials for potential application as electrodes in advanced secondary battery designs. The details and results of our efforts for the first year are presented in Technical Report No. 2. The present report covers the first six months of effort in the second year.

Huggins, R.A.

1974-11-30T23:59:59.000Z

205

Solid composite electrolytes for lithium batteries  

DOE Patents (OSTI)

Solid composite electrolytes are provided for use in lithium batteries which exhibit moderate to high ionic conductivity at ambient temperatures and low activation energies. In one embodiment, a polymer-ceramic composite electrolyte containing poly(ethylene oxide), lithium tetrafluoroborate and titanium dioxide is provided in the form of an annealed film having a room temperature conductivity of from 10.sup.-5 S cm.sup.-1 to 10.sup.-3 S cm.sup.-1 and an activation energy of about 0.5 eV.

Kumar, Binod (Dayton, OH); Scanlon, Jr., Lawrence G. (Fairborn, OH)

2001-01-01T23:59:59.000Z

206

Continuous aqueous tritium monitor  

DOE Patents (OSTI)

An apparatus for a selective on-line determination of aqueous tritium concentration is disclosed. A moist air stream of the liquid solution being analyzed is passed through a permeation dryer where the tritium and moisture are selectively removed to a purge air stream. The purge air stream is then analyzed for tritium concentration, humidity, and temperature, which allows computation of liquid tritium concentration. 2 figs.

McManus, G.J.; Weesner, F.J.

1987-10-19T23:59:59.000Z

207

Electrolytes: transport properties and non-equilibrium thermodynamics  

Science Conference Proceedings (OSTI)

This paper presents a review on the application of non-equilibrium thermodynamics to transport in electrolyte solutions, and some recent experimental work and results for mutual diffusion in electrolyte solutions.

Miller, D.G.

1980-12-01T23:59:59.000Z

208

Thermodynamics and Ionic Conductivity of Block Copolymer Electrolytes  

E-Print Network (OSTI)

of Poly(Ethylene Oxide) Molten-Salt Rubbery Electrolytes.Imides: A New Family of Molten Salts and Conductive Plasticof Poly(Ethylene Oxide) Molten-Salt Rubbery Electrolytes.

Wanakule, Nisita Sidra

2010-01-01T23:59:59.000Z

209

Passivation of Aluminum in Lithium-ion Battery Electrolytes with LiBOB  

E-Print Network (OSTI)

of Aluminum in Lithium-ion Battery Electrolytes with LiBOBin commercially available lithium-ion battery electrolytes,

Zhang, Xueyuan; Devine, Thomas M.

2008-01-01T23:59:59.000Z

210

2007 Status of Manufacturing: Polymer Electrolyte Membrane (PEM) Fuel Cells  

DOE Green Energy (OSTI)

In this document we assess the North American industry's current ability to manufacture polymer electrolyte membrane (PEM) fuel cells.

Wheeler, D.; Sverdrup, G.

2008-03-01T23:59:59.000Z

211

Electrolytic Cell For Production Of Aluminum From Alumina  

SciTech Connect

An electrolytic cell for producing aluminum from alumina having a reservoir for collecting molten aluminum remote from the electrolysis.

Bradford, Donald R (Underwood, WA); Barnett, Robert J. (Goldendale, WA); Mezner, Michael B. (Sandy, OR)

2004-11-02T23:59:59.000Z

212

Solar Thermal Electrolytic Production of Metals from Their Oxides  

Science Conference Proceedings (OSTI)

Symposium, Alternative Energy Resources for Metals and Materials Production Symposium. Presentation Title, Solar Thermal Electrolytic Production of Metals ...

213

Electrode electrolyte interlayers containing cerium oxide for electrochemical fuel cells  

DOE Patents (OSTI)

An electrochemical cell is made having a porous fuel electrode (16) and a porous air electrode (13), with solid oxide electrolyte (15) therebetween, where the air electrode surface opposing the electrolyte has a separate, attached, dense, continuous layer (14) of a material containing cerium oxide, and where electrolyte (16) contacts the continuous oxide layer (14), without contacting the air electrode (13).

Borglum, Brian P. (Edgewood, PA); Bessette, Norman F. (N. Huntingdon, PA)

2000-01-01T23:59:59.000Z

214

Atomistic insights into aqueous corrosion of copper.  

SciTech Connect

Corrosion is a fundamental problem in electrochemistry and represents a mode of failure of technologically important materials. Understanding the basic mechanism of aqueous corrosion of metals such as Cu in presence of halide ions is hence essential. Using molecular dynamics simulations incorporating reactive force-field (ReaxFF), the interaction of copper substrates and chlorine under aqueous conditions has been investigated. These simulations incorporate effects of proton transfer in the aqueous media and are suitable for modeling the bond formation and bond breakage phenomenon that is associated with complex aqueous corrosion phenomena. Systematic investigation of the corrosion process has been carried out by simulating different chlorine concentration and solution states. The structural and morphological differences associated with metal dissolution in the presence of chloride ions are evaluated using dynamical correlation functions. The simulated atomic trajectories are used to analyze the charged states, molecular structure and ion density distribution which are utilized to understand the atomic scale mechanism of corrosion of copper substrates under aqueous conditions. Increased concentration of chlorine and higher ambient temperature were found to expedite the corrosion of copper. In order to study the effect of solution states on the corrosion resistance of Cu, partial fractions of proton or hydroxide in water were configured, and higher corrosion rate at partial fraction hydroxide environment was observed. When the Cl{sup -} concentration is low, oxygen or hydroxide ion adsorption onto Cu surface has been confirmed in partial fraction hydroxide environment. Our study provides new atomic scale insights into the early stages of aqueous corrosion of metals such as copper.

Jeon, B.; Sankaranarayanan, S. K. R. S.; van Duin, A. C. T.; Ramanathan, S. (Center for Nanoscale Materials); (Harvard Univ.); (Penn State Univ.)

2011-06-21T23:59:59.000Z

215

Ultrasonic hydrometer. [Specific gravity of electrolyte  

DOE Patents (OSTI)

The disclosed ultrasonic hydrometer determines the specific gravity (density) of the electrolyte of a wet battery, such as a lead-acid battery. The hydrometer utilizes a transducer that when excited emits an ultrasonic impulse that traverses through the electrolyte back and forth between spaced sonic surfaces. The transducer detects the returning impulse, and means measures the time t between the initial and returning impulses. Considering the distance d between the spaced sonic surfaces and the measured time t, the sonic velocity V is calculated with the equation V = 2d/t. The hydrometer also utilizes a thermocouple to measure the electrolyte temperature. A hydrometer database correlates three variable parameters including sonic velocity in and temperature and specific gravity of the electrolyte, for temperature values between 0 and 40/sup 0/C and for specific gravity values between 1.05 and 1.30. Upon knowing two parameters (the calculated sonic velocity and the measured temperature), the third parameter (specific gravity) can be uniquely found in the database. The hydrometer utilizes a microprocessor for data storage and manipulation.

Swoboda, C.A.

1982-03-09T23:59:59.000Z

216

Process for electrolytically preparing uranium metal  

DOE Patents (OSTI)

A process for making uranium metal from uranium oxide by first fluorinating uranium oxide to form uranium tetrafluoride and next electrolytically reducing the uranium tetrafluoride with a carbon anode to form uranium metal and CF.sub.4. The CF.sub.4 is reused in the fluorination reaction rather than being disposed of as a hazardous waste.

Haas, Paul A. (Knoxville, TN)

1989-01-01T23:59:59.000Z

217

A study of electrolytic tritium production  

SciTech Connect

Tritium production is being investigated using cathodes made from palladium and its alloys with various surface treatments. Three anode materials have been studied as well as different impurities in the electrolyte. Tritium has been produced in about 10% of the cells studied but there is, as yet, no pattern of behavior that would make the effect predictable. 15 refs., 4 figs., 6 tabs.

Storms, E.K.; Talcott, C.L.

1990-01-01T23:59:59.000Z

218

Electrolytic plating apparatus for discrete microsized particles  

SciTech Connect

Method and apparatus are disclosed for electrolytically producing very uniform coatings of a desired material on discrete microsized particles. Agglomeration or bridging of the particles during the deposition process is prevented by imparting a sufficiently random motion to the particles that they are not in contact with a powered cathode for a time sufficient for such to occur.

Mayer, Anton (Los Alamos, NM)

1976-11-30T23:59:59.000Z

219

Anhydrous hydrogen fluoride electrolyte battery. [Patent application  

DOE Patents (OSTI)

It is an object of the invention to provide a primary cell or battery using ammonium fluoride--anhydrous hydrogen fluoride electrolyte having improved current and power production capabilities at low temperatures. It is operable at temperatures substantially above the boiling point of hydrogen fluoride. (GRA)

Not Available

1972-06-26T23:59:59.000Z

220

LOWER TEMPERATURE ELECTROLYTE AND ELECTRODE MATERIALS  

DOE Green Energy (OSTI)

A thorough literature survey on low-temperature electrolyte and electrode materials for solid oxide fuel cells (SOFC) is presented. Preliminary results of co-sintering LaGaO{sub 3} (LSGM) film on the cathode substrate were also reported. The chemical stability of LSGM in various SOFC environments was thermodynamically assessed and verified by the molten-salt technique.

Keqin Huang

2001-04-30T23:59:59.000Z

Note: This page contains sample records for the topic "aqueous electrolyte modeling" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Fuel cell electrolyte membrane with basic polymer  

DOE Patents (OSTI)

The present invention is an electrolyte membrane comprising an acid and a basic polymer, where the acid is a low-volatile acid that is fluorinated and is either oligomeric or non-polymeric, and where the basic polymer is protonated by the acid and is stable to hydrolysis.

Larson, James M. (Saint Paul, MN); Pham, Phat T. (Little Canada, MN); Frey, Matthew H. (Cottage Grove, MN); Hamrock, Steven J. (Stillwater, MN); Haugen, Gregory M. (Edina, MN); Lamanna, William M. (Stillwater, MN)

2010-11-23T23:59:59.000Z

222

Towards Understanding the Poor Thermal Stability of V5+ Electrolyte Solution in Vanadium Redox Flow Batteries  

DOE Green Energy (OSTI)

The V5+ electrolyte solution from vanadium redox flow batteries was studied by variable temperature 17O and 51V Nuclear Magnetic Resonance (NMR) spectroscopy and DFT based computational modeling. It was found that the V5+ species exist as hydrated penta co-ordinated vanadate ion, i.e. [VO2(H2O)3]1+. This hydrated structure is not stable at elevated temperature and change into neutral H3VO4 molecule via a deprotonation process. H3VO4 species is also knowingly unstable, leading to the observed V2O5 precipitation in V5+ electrolyte solutions.

Vijayakumar, M.; Li, Liyu; Graff, Gordon L.; Liu, Jun; Zhang, Huamin; Yang, Zhenguo; Hu, Jian Z.

2011-04-01T23:59:59.000Z

223

Method and apparatus for storage battery electrolyte circulation  

SciTech Connect

An electrolyte reservoir in fluid communication with the cell of a storage battery is intermittently pressurized with a pulse of compressed gas to cause a flow of electrolyte from the reservoir to the upper region of less dense electrolyte in the cell. Upon termination of the pressure pulse, more dense electrolyte is forced into the reservoir from the lower region of the cell by the differential pressure head between the cell and reservoir electrolyte levels. The compressed gas pulse is controlled to prevent the entry of gas from the reservoir into the cell.

Inkmann, Mark S. (Milwaukee, WI)

1980-09-09T23:59:59.000Z

224

Fuel cell and system for supplying electrolyte thereto  

DOE Patents (OSTI)

An electrolyte distribution and supply system for use with a fuel cell having means for drawing electrolyte therein is formed by a set of containers of electrolyte joined to respective fuel cells in a stack of such cells. The electrolyte is separately stored so as to provide for electrical isolation between electrolytes of the individual cells of the stack. Individual storage compartments are coupled by capillary tubes to the respective fuel cells. Hydrostatic pressure is maintained individually for each of the fuel cells by separately elevating each compartment of the storing means to a specific height above the corresponding fuel cell which is to be fed from that compartment of the storing means. The individual compartments are filled with electrolyte by allowing the compartments to overflow thereby maintaining the requisite depth of electrolyte in each of the storage compartments.

Adlhart, Otto J. (Tenafly, NJ); Feigenbaum, Haim (Highland Park, NJ)

1984-01-01T23:59:59.000Z

225

Selective adsorption of uranium on activated charcoal from electrolytic aqueous solutions  

SciTech Connect

Adsorption of uranium onto various solids is important from purification, environmental, and radioactive waste disposal points of view. Adsorption of uranium on activated charcoal has been studied as a function of shaking time, amount of adsorbent, pH, concentration of adsorbate, and temperature. Uranium adsorption obeys the Langmuir isotherm. {Delta}H{degrees} and {Delta}S{degrees} were calculated from the slope and intercept of plots ln K{sub D} vs 1/T. The influence of different anions and cations on uranium adsorption has been examined. The adsorption of other metal ions on activated charcoal has been studied under specified conditions to check its selectivity; consequently, uranium was removed from Cs, Ba, Zn, and Co. More than 98% adsorbed uranium on activated charcoal can be recovered with 65 ml of 3 M HNO{sub 3} solution. A wavelength dispersive x-ray fluorescence spectrometer was used for measuring uranium concentration.

Saleem, M.; Afzal, M. (Quaid-I-Azam Univ., Islamabad (Pakistan)); Qadeer, R.; Hanif, J. (Pakistan Institute of Nuclear Science and Technology, Islamabad (Pakistan))

1992-02-01T23:59:59.000Z

226

Behavior of Aqueous Electrolytes in Steam Cycles: The Solubility and Volatility of Cupric Oxide  

Science Conference Proceedings (OSTI)

Uncontrolled copper transport activity represents a potentially significant source of performance and reliability loss to fossil plants with mixed-metallurgy feedwater systems. Recent utility experiences with severe copper turbine fouling and other related problems identified the need for basic fundamental research to improve industry understanding of the volatility and solubility of copper and its oxides.

2000-12-08T23:59:59.000Z

227

Modified SDOF Models for Improved Representation of the Impact Response  

E-Print Network (OSTI)

requires electrolytics #12;Reliability predictor models · MIL-HDBK 217F ­ Last updated in 1995 ­ Does

Feraboli, Paolo

228

Electrolyte reservoir for carbonate fuel cells  

DOE Patents (OSTI)

An electrode for a carbonate fuel cell and method of making same are described wherein a substantially uniform mixture of an electrode-active powder and porous ceramic particles suitable for a carbonate fuel cell are formed into an electrode with the porous ceramic particles having pores in the range of from about 1 micron to about 3 microns, and a carbonate electrolyte is in the pores of the ceramic particles.

Iacovangelo, C.D.; Shores, D.A.

1984-05-23T23:59:59.000Z

229

Electrolyte reservoir for carbonate fuel cells  

DOE Patents (OSTI)

An electrode for a carbonate fuel cell and method of making same wherein a substantially uniform mixture of an electrode-active powder and porous ceramic particles suitable for a carbonate fuel cell are formed into an electrode with the porous ceramic particles having pores in the range of from about 1 micron to about 3 microns, and a carbonate electrolyte is in the pores of the ceramic particles.

Iacovangelo, Charles D. (Schenectady, NY); Shores, David A. (Minneapolis, MN)

1985-01-01T23:59:59.000Z

230

Market potential for electrolytic hydrogen. Final report  

SciTech Connect

The economics of hydrogen production by the major users of hydrogen (petroleum refiners and manufacturers of ammonia and methanol) favor the continued use of fossil fuels for hydrogen generation. However, there are a large number of miscellaneous small users for whom hydrogen produced by advanced electrolyzers may become economically attractive. Many of these small users, with hydrogen demands of < 0.5 million SCF per day, purchase their hydrogen requirements from industrial gas suppliers. Forseeable improvements in current electrolyzer technology, which will reduce plant capital costs and improve plant performance and efficiency, may make electrolytic hydrogen competitive with purchased hydrogen for many specialty users. This study analyzed the small user hydrogen market. Telephone interviews were conducted with representative hydrogen users in the chemical, pharmaceutical, electronics, metals, fats and oils, and float glass industries to determine the decision factors governing the choice of their hydrogen supply. Cost projections to the year 2000 for production of hydrogen by advanced electrolyzers were made and compared with price projections for merchant hydrogen, and the estimates of the potential market for each of the industrial sub-sectors were determined. By the year 2000, the potential market for advanced technology electrolytic hydrogen among specialty users is projected to be about half of what the merchant hydrogen market would be in the absence of electrolytic hydrogen. This potential market, representing an annual demand of about 16 billion SCF of hydrogen, will develop from market penetrations of electrolyzers assumed to begin in the early 1980s.

Fein, E.; Mathey, C.J.; Arnstein, C.

1979-08-01T23:59:59.000Z

231

Nonaqueous Electrolyte Development for Electrochemical Capacitors  

DOE Green Energy (OSTI)

The objectives of this project were to demonstrate and develop new nonaqueous electrolytes that enable the development of high power (in excess of 2 kW/kg) and high energy (in excess of 8 Wh/kg) capacitors. Electrochemical capacitors are attractive to use because of their long cycle life and inherent high-power (or fast charge/discharge) capabilities. To realize the inherent high-power nature of the capacitor, the resistance of the capacitor needs to be low. The main focus of this project is on the ionic part of capacitor resistance, which is largely determined by the electrolyte, especially the electrolyte's conductivity. To achieve the objectives of this project, two approaches were used. The first was to search for the proper solvent mixtures within the commercially available quaternary ammonium salts such as tetraethyl ammonium tetrafluoroborate (Et4NBF4) or tetraethyl ammonium hexafluorophosphate (Et4NPF6). The second approach was to use the commonly available solvent system s but develop new salts. Substantial advances were made in quaternary ammonium salts and solvent systems were identified that can withstand high voltage operations. However, improvement in the salt alone is not sufficient. Improvements in the low-temperature stability of a capacitor rely not only on the salts but also on the solvents. Likewise, the high-temperature stability of the capacitor will depend not only on the salts but also on the solvents and carbon electrode materials.

K. Xu; S. P. Ding; T. R. Jow

1999-09-01T23:59:59.000Z

232

Electrolytic method to make alkali alcoholates using ion conducting alkali electrolyte/separator  

DOE Patents (OSTI)

Alkali alcoholates, also called alkali alkoxides, are produced from alkali metal salt solutions and alcohol using a three-compartment electrolytic cell. The electrolytic cell includes an anolyte compartment configured with an anode, a buffer compartment, and a catholyte compartment configured with a cathode. An alkali ion conducting solid electrolyte configured to selectively transport alkali ions is positioned between the anolyte compartment and the buffer compartment. An alkali ion permeable separator is positioned between the buffer compartment and the catholyte compartment. The catholyte solution may include an alkali alcoholate and alcohol. The anolyte solution may include at least one alkali salt. The buffer compartment solution may include a soluble alkali salt and an alkali alcoholate in alcohol.

Joshi, Ashok V. (Salt Lake City, UT); Balagopal, Shekar (Sandy, UT); Pendelton, Justin (Salt Lake City, UT)

2011-12-13T23:59:59.000Z

233

STABLE HIGH CONDUCTIVITY BILAYERED ELECTROLYTES FOR LOW TEMPERATURE SOLID OXIDE FUEL CELLS  

DOE Green Energy (OSTI)

Solid oxide fuel cells (SOFCs) are the future of energy production in America. They offer great promise as a clean and efficient process for directly converting chemical energy to electricity while providing significant environmental benefits (they produce negligible CO, HC, or NOx and, as a result of their high efficiency, produce about one-third less CO{sub 2} per kilowatt hour than internal combustion engines). Unfortunately, the current SOFC technology, based on a stabilized zirconia electrolyte, must operate in the region of 1000 C to avoid unacceptably high ohmic losses. These high temperatures demand (a) specialized (expensive) materials for the fuel cell interconnects and insulation, (b) time to heat up to the operating temperature and (c) energy input to arrive at the operating temperature. Therefore, if fuel cells could be designed to give a reasonable power output at lower temperatures tremendous benefits may be accrued, not the least of which is reduced cost. The problem is, at lower temperatures the conductivity of the conventional stabilized zirconia electrolyte decreases to the point where it cannot supply electrical current efficiently to an external load. The primary objectives of the proposed research is to develop a stable high conductivity (>0.05 S cm{sup -1} at 550 C) electrolyte for lower temperature SOFCs. This objective is specifically directed toward meeting the lowest (and most difficult) temperature criteria for the 21st Century Fuel Cell Program. Meeting this objective provides a potential for future transportation applications of SOFCs, where their ability to directly use hydrocarbon fuels could permit refueling within the existing transportation infrastructure. In order to meet this objective we are developing a functionally gradient bilayer electrolyte comprised of bismuth oxide on the air side and ceria on the fuel side. Bismuth oxide and doped ceria are among the highest ionic conducting electrolytes and in fact bismuth oxide based electrolytes are the only known solid oxide electrolytes to have an ionic conductivity that meets the program conductivity goal. We have previously demonstrated that this concept works, that a bismuth oxide/ceria bilayer electrolyte provides near theoretical open circuit potential (OCP) and is stable for 1400 h of fuel cell operation under both open circuit and maximum power conditions. More recently, we developed a computer model to determine the defect transport in this bilayer and have found that a bilayer comprised primarily of the more conductive component (bismuth oxide) is stable for 500 C operation. In this first year of the project we are obtaining necessary thermochemical data to complete the computer model as well as initial SOFC results based on thick 1-2 mm single and bilayer ceria/bismuth oxide electrolytes. We will use the computer model to obtain the optimum relative layer thickness as a function of temperature and air/fuel conditions. SOFCs will be fabricated with 1-2 mm single and bilayer electrolytes based on the modeling results, tested for OCP, conductivity, and stability and compared against the predictions. The computer modeling is a continuation of previous work under support from GRI and the student was available at the inception of the contract. However, the experimental effort was delayed until the beginning of the Spring Semester because the contract was started in October, 2 months after the start of our Fall Semester, and after all of the graduate students were committed to other projects. The results from both of these efforts are described in the following two sections: (1) Experimental; and (2) Computer Modeling.

Eric D. Wachsman

2000-10-01T23:59:59.000Z

234

STABLE HIGH CONDUCTIVITY BILAYERED ELECTROLYTES FOR LOW TEMPERATURE SOLID OXIDE FUEL CELLS  

DOE Green Energy (OSTI)

A bilayer electrolyte consisting of acceptor-doped ceria (on the fuel/reducing side) and cubic-stabilized bismuth oxide (on the oxidizing side) was developed. The bilayer electrolyte that was developed showed significant improvement in open-circuit potential versus a typical ceria based SOFC. Moreover, the OCP of the bilayer cells increased as the thickness of the bismuth oxide layer increased relative to the ceria layer. Thereby, verifying the bilayer concept. Although, because of the absence of a suitable cathode (a problem we are still working assiduously to solve), we were unable to obtain power density curves, our modeling work predicts a reduction in electrolyte area specific resistance of two orders of magnitude over cubic-stabilized zirconia and projects a maximum power density of 9 W/m{sup 2} at 800 C and 0.09 W/m{sup 2} at 500 C. Towards the development of the bilayer electrolyte other significant strides were made. Among these were, first, the development of a, bismuth oxide based, oxide ion conductor with the highest conductivity (0.56 S/cm at 800 C and 0.043 S/cm at 500 C) known to date. Second, a physical model of the defect transport mechanisms and the driving forces for the ordering phenomena in bismuth oxide and other fluorite systems was developed. Third, a model for point defect transport in oxide mixed ionic-electronic conductors was developed, without the typical assumption of a uniform distribution of ions and including the effect of variable loads on the transport properties of an SOFC (with either a single or bilayer electrolyte).

Eric D. Wachsman; Keith L. Duncan

2002-09-30T23:59:59.000Z

235

AQUEOUS ELECTROTECHNOLOGIES: PROGRESS IN THEORY ...  

Science Conference Proceedings (OSTI)

Cathodic and anodic reactions in the acidic nitrate medium were studied in ... of nitrous acid was investigated in the range of 0.5 to 3.0 M nitric acid, 0.0 to 0.1 ... Iron (VI) is most conveniently manufactured electrolytically via the dissolution of .... acids in the steel industry and anodizing solutions in the aluminum industry.

236

Electrolyte matrix in a molten carbonate fuel cell stack  

DOE Patents (OSTI)

A fuel cell stack is disclosed with modified electrolyte matrices for limiting the electrolytic pumping and electrolyte migration along the stack external surfaces. Each of the matrices includes marginal portions at the stack face of substantially greater pore size than that of the central body of the matrix. Consequently, these marginal portions have insufficient electrolyte fill to support pumping or wicking of electrolyte from the center of the stack of the face surfaces in contact with the vertical seals. Various configurations of the marginal portions include a complete perimeter, opposite edge portions corresponding to the air plenums and tab size portions corresponding to the manifold seal locations. These margins will substantially limit the migration of electrolyte to and along the porous manifold seals during operation of the electrochemical cell stack. 6 figs.

Reiser, C.A.; Maricle, D.L.

1987-04-21T23:59:59.000Z

237

Electrolyte matrix in a molten carbonate fuel cell stack  

DOE Patents (OSTI)

A fuel cell stack is disclosed with modified electrolyte matrices for limiting the electrolytic pumping and electrolyte migration along the stack external surfaces. Each of the matrices includes marginal portions at the stack face of substantially greater pore size than that of the central body of the matrix. Consequently, these marginal portions have insufficient electrolyte fill to support pumping or wicking of electrolyte from the center of the stack of the face surfaces in contact with the vertical seals. Various configurations of the marginal portions include a complete perimeter, opposite edge portions corresponding to the air plenums and tab size portions corresponding to the manifold seal locations. These margins will substantially limit the migration of electrolyte to and along the porous manifold seals during operation of the electrochemical cell stack.

Reiser, Carl A. (Glastonbury, CT); Maricle, Donald L. (Glastonbury, CT)

1987-04-21T23:59:59.000Z

238

Electrolyte matrix in a molten carbonate fuel cell stack  

DOE Patents (OSTI)

A fuel cell stack is disclosed with modified electrolyte matrices for limiting the electrolytic pumping and electrolyte migration along the stack external surfaces. Each of the matrices includes marginal portions at the stack face of substantially greater pore size than that of the central body of the matrix. Consequently, these marginal portions have insufficient electrolyte fill to support pumping or wicking of electrolyte from the center of the stack to the face surfaces in contact with the vertical seals. Various configurations of the marginal portions include a complete perimeter, opposite edge portions corresponding to the air plenums and tab size portions corresponding to the manifold seal locations. These margins will substantially limit the migration of electrolyte to and along the porous manifold seals during operation of the electrochemical cell stack.

Reiser, C.A.; Maricle, D.L.

1986-05-27T23:59:59.000Z

239

Polymer Electrolyte Fuel Cell Lifetime Limitations: The Role...  

NLE Websites -- All DOE Office Websites (Extended Search)

of polymer electrolyte membrane fuel cell (PEMFC) performance, Establish dominant catalyst and cathode degradation * mechanisms for Pt, Pt-Co alloys, and Pt 3 Sc, Identify key...

240

STUDIES ON ZINC NODULES ELECTRODEPOSITED FROM ACID ELECTROLYTES  

E-Print Network (OSTI)

Electrolytic Nucleation Brass on Platinum Single Crystalepoxied to a which threaded brass mount. This was then setmechanical polishing. A tapered brass mount was used a dummy

Anderson, R.

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "aqueous electrolyte modeling" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Method of synthesizing polymers from a solid electrolyte  

DOE Patents (OSTI)

A method of synthesizing electrically conductive polymers from a solvent-free solid polymer electrolyte is disclosed. An assembly of a substrate having an electrode thereon, a thin coating of solid electrolyte including a solution of PEO complexed with an alkali salt, and a thin transparent noble metal electrode are disposed in an evacuated chamber into which a selected monomer vapor is introduced while an electric potential is applied across the solid electrolyte to hold the thin transparent electrode at a positive potential relative to the electrode on the substrate, whereby a highly conductive polymer film is grown on the transparent electrode between it and the solid electrolyte.

Skotheim, T.A.

1984-10-19T23:59:59.000Z

242

Autogenous electrolyte, non-pyrolytically produced solid capacitor structure  

DOE Patents (OSTI)

This report discusses the design of a solid electrolytic capacitor having a solid electrolyte comprised of manganese dioxide dispersed in an aromatic polyamide capable of to forming polyimide linkages. This solid electrolyte being disposed between a first electrode made of valve metal covered by an anodic oxide film and a second electrode opposite the first electrode. The electrolyte autogenously produces water, oxygen, and hydroxyl groups which act as healing substances and is not itself produced pyrolytically. Reduction of the manganese dioxide and the water molecules released by formation of imide linkages result in substantially improved self-healing of anodic dielectric layer defects.

Sharp, D.J.; Armstrong, P.S.; Paintz, J.K.G.

1998-04-01T23:59:59.000Z

243

Autogenous electrolyte, non-pyrolytically produced solid capacitor structure  

DOE Patents (OSTI)

A solid electrolytic capacitor having a solid electrolyte comprising manganese dioxide dispersed in an aromatic polyamide capable of further cure to form polyimide linkages, the solid electrolyte being disposed between a first electrode made of valve metal covered by an anodic oxide film and a second electrode opposite the first electrode. The electrolyte autogenously produces water, oxygen, and hydroxyl groups which act as healing substances and is not itself produced pyrolytically. Reduction of the manganese dioxide and the water molecules released by formation of imide linkages result in substantially improved self-healing of anodic dielectric layer defects.

Sharp, Donald J. (Albuquerque, NM); Armstrong, Pamela S. (Abingdon, MD); Panitz, Janda Kirk G. (Edgewood, NM)

1998-01-01T23:59:59.000Z

244

Novel Electrolyte Enables Stable Graphite Anodes in Lithium Ion Batteries  

Berkeley Lab researchers led by Gao Liu have developed an improved lithium ion battery electrolyte containing a solvent that remains liquid at typical ...

245

ESS 2012 Peer Review - Organic and Inorganic Solid Electrolytes...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Good match between calculated and synthesized electrolyte (crystal structure and lattice parameters) Figure 9: Actual battery pellet and first cycle voltage profile of the...

246

2007 Status of Manufacturing: Polymer Electrolyte Membrane (PEM) Fuel Cells  

SciTech Connect

In this document we assess the North American industry's current ability to manufacture polymer electrolyte membrane (PEM) fuel cells.

Wheeler, D.; Sverdrup, G.

2008-03-01T23:59:59.000Z

247

Zinc halogen battery electrolyte composition with lead additive  

SciTech Connect

This disclosure relates to a zinc halogen battery electrolyte composition containing an additive providing improved zinc-on-zinc recyclability. The improved electrolyte composition involves the use of a lead additive to inhibit undesirable irregular plating and reduce nodular or dendritic growth on the electrode surface. The lead-containing electrolyte composition of the present invention appears to influence not only the morphology of the base plate zinc, but also the morphology of the zinc-on-zinc replate. In addition, such lead-containing electrolyte compositions appear to reduce hydrogen formation.

Henriksen, Gary L. (Troy, MI)

1981-01-01T23:59:59.000Z

248

NASICON-Type Electrolytes for Low Temperature Sodium Battery ...  

Science Conference Proceedings (OSTI)

Presentation Title, NASICON-Type Electrolytes for Low Temperature Sodium Battery Applications. Author(s), Hui Zhang, Xingbo Liu. On-Site Speaker ( Planned) ...

249

Layer-by-Layer Assembled Thin Films for Battery Electrolytes  

Science Conference Proceedings (OSTI)

Presentation Title, Layer-by-Layer Assembled Thin Films for Battery Electrolytes ... Abstract Scope, Exponential layer-by-layer (eLBL) assembled battery ...

250

Solid Electrolyte Developed for Safer Lithium-Ion Batteries  

Science Conference Proceedings (OSTI)

Feb 19, 2013 ... Today's lithium-ion batteries rely on a liquid electrolyte to conduct ions between the negatively charged anode and positive cathode.

251

Proton Channel Orientation in Block-Copolymer Electrolyte Membranes  

NLE Websites -- All DOE Office Websites (Extended Search)

Proton Channel Orientation in Block-Copolymer Electrolyte Membranes Print Fuel cells have the potential to provide power for a wide variety of applications ranging from electronic...

252

Short protection device for stack of electrolytic cells  

DOE Patents (OSTI)

The present invention relates to a device for preventing the electrical shorting of a stack of electrolytic cells during an extended period of operation. The device has application to fuel cell and other electrolytic cell stacks operating in low or high temperature corrosive environments. It is of particular importance for use in a stack of fuel cells operating with molten metal carbonate electrolyte for the production of electric power. Also, the device may have application in similar technology involving stacks of electrolytic cells for electrolysis to decompose chemical compounds.

Katz, M.; Schroll, C.R.

1984-11-29T23:59:59.000Z

253

Copper Refining Electrolyte Purification by the Use of Molecular ...  

Science Conference Proceedings (OSTI)

Presentation Title, Copper Refining Electrolyte Purification by the Use of Molecular ... An Experimental Study of Chemical Oxygen Demand Removal from the ...

254

Investigation of 5 MOL% YSZ Electrolyte for SOFC  

Science Conference Proceedings (OSTI)

Presentation Title, Investigation of 5 MOL% YSZ Electrolyte for SOFC. Author(s), Nilufer Evcimen, Ahmet Ekerim. On-Site Speaker (Planned), Nilufer Evcimen.

255

Carbonate fuel cell endurance: Hardware corrosion and electrolyte management status  

DOE Green Energy (OSTI)

Endurance tests of carbonate fuel cell stacks (up to 10,000 hours) have shown that hardware corrosion and electrolyte losses can be reasonably controlled by proper material selection and cell design. Corrosion of stainless steel current collector hardware, nickel clad bipolar plate and aluminized wet seal show rates within acceptable limits. Electrolyte loss rate to current collector surface has been minimized by reducing exposed current collector surface area. Electrolyte evaporation loss appears tolerable. Electrolyte redistribution has been restrained by proper design of manifold seals.

Yuh, C.; Johnsen, R.; Farooque, M.; Maru, H.

1993-01-01T23:59:59.000Z

256

Carbonate fuel cell endurance: Hardware corrosion and electrolyte management status  

DOE Green Energy (OSTI)

Endurance tests of carbonate fuel cell stacks (up to 10,000 hours) have shown that hardware corrosion and electrolyte losses can be reasonably controlled by proper material selection and cell design. Corrosion of stainless steel current collector hardware, nickel clad bipolar plate and aluminized wet seal show rates within acceptable limits. Electrolyte loss rate to current collector surface has been minimized by reducing exposed current collector surface area. Electrolyte evaporation loss appears tolerable. Electrolyte redistribution has been restrained by proper design of manifold seals.

Yuh, C.; Johnsen, R.; Farooque, M.; Maru, H.

1993-05-01T23:59:59.000Z

257

Fabrication of Solid Electrolyte Dendrites for Solid Oxide Fuel Cell ...  

Science Conference Proceedings (OSTI)

Fabrication of Solid Electrolyte Dendrites for Solid Oxide Fuel Cell Miniaturizations · Fabrication of TiN Nanoparticle Dispersed Si3N4 Ceramics by Wet Jet ...

258

SISGR: Linking Ion Solvation and Lithium Battery Electrolyte Properties  

DOE Green Energy (OSTI)

The solvation and phase behavior of the model battery electrolyte salt lithium trifluoromethanesulfonate (LiCF3SO3) in commonly used organic solvents; ethylene carbonate (EC), gamma-butyrolactone (GBL), and propylene carbonate (PC) was explored. Data from differential scanning calorimetry (DSC), Raman spectroscopy, and X-ray diffraction were correlated to provide insight into the solvation states present within a sample mixture. Data from DSC analyses allowed the construction of phase diagrams for each solvent system. Raman spectroscopy enabled the determination of specific solvation states present within a solvent-Ã?Â?Ã?Â?salt mixture, and X-ray diffraction data provided exact information concerning the structure of a solvates that could be isolated Thermal analysis of the various solvent-salt mixtures revealed the phase behavior of the model electrolytes was strongly dependent on solvent symmetry. The point groups of the solvents were (in order from high to low symmetry): C2V for EC, CS for GBL, and C1 for PC(R). The low symmetry solvents exhibited a crystallinity gap that increased as solvent symmetry decreased; no gap was observed for EC-LiTf, while a crystallinity gap was observed spanning 0.15 to 0.3 mole fraction for GBL-LiTf, and 0.1 to 0.33 mole fraction for PC(R)-LiTf mixtures. Raman analysis demonstrated the dominance of aggregated species in almost all solvent compositions. The AGG and CIP solvates represent the majority of the species in solutions for the more concentrated mixtures, and only in very dilute compositions does the SSIP solvate exist in significant amounts. Thus, the poor charge transport characteristics of CIP and AGG account for the low conductivity and transport properties of LiTf and explain why is a poor choice as a source of Li+ ions in a Li-ion battery.

Trulove, Paul C; Foley, Matthew P

2013-03-14T23:59:59.000Z

259

Thermal conductivity of aqueous foam  

Science Conference Proceedings (OSTI)

Thermal conductivity plays an important part in the response of aqueous foams used as geothermal drilling fluids. The thermal conductivity of these foams was measured at ambient conditions using the thermal conductivity probe technique. Foam densities studied were from 0.03 to 0.2 g/cm/sup 3/, corresponding to liquid volume fractions of the same magnitude. Microscopy of the foams indicated bubble sizes in the range 50 to 300 ..mu..m for nitrogen foams, and 30 to 150 ..mu..m for helium foams. Bubble shapes were observed to be polyhedral at low foam densities and spherical at the higher densities. The measured conductivity values ranged from 0.05 to 0.12 W/m-K for the foams studied. The predicted behavior in foam conductivity caused by a change in the conductivity of the discontinuous gas phase was observed using nitrogen or helium gas in the foams. Analysis of the probe response data required an interpretation using the full intergral solution to the heat conduction equation, since the thermal capacity of the foam was small relative to the thermal mass of the probe. The measurements of the thermal conductivity of the foams were influenced by experimental effects such as the probe input power, foam drainage, and the orientation of the probe and test cell. For nitrogen foams, the thermal conductivity vs liquid volume fraction was observed to fall between predictions based on the parallel ordering and Russell models for thermal conduction in heterogeneous materials.

Drotning, W.D.; Ortega, A.; Havey, P.E.

1982-05-01T23:59:59.000Z

260

Electrolytic decontamination of the 3013 inner can  

SciTech Connect

Disposition of plutonium recovered from nuclear weapons or production residues must be stored in a manner that ensures safety. The criteria that has been established to assure the safety of stored materials for a minimum of 50 years is DOE-STD-3013. This standard specifies both the requirements for containment and furthermore specifies that the inner container be decontaminated to a level of {le}20 dpm/100 cm{sup 2} swipable and {le}500 dpm/100 cm{sup 2} direct alpha such that a failure of the outer containment barrier will have a lower probability of resulting in a spread of contamination. The package consists of an optional convenience (food pack) can, a welded type 304L stainless steel inner (primary) can, and a welded type 304L stainless steel outer (secondary) can. Following the welding process, the can is checked for leaks and then sent down the line for decontamination. Once decontaminated, the sealed primary can may be removed from the glove box line. Welding of the secondary container takes place outside the glove box line. The highly automated decontamination process that has been developed to support the packaging of Special Nuclear Materials is based on an electrolytic process similar to the wide spread industrial technique of electropolishing. The can is placed within a specially designed stainless steel fixture built within a partition of a glove box. The passage of current through this electrolytic cell results in a uniform anodic dissolution of the surface metal layers of the can. This process results in a rapid decontamination of the can. The electrolyte is fully recyclable, and the separation of the chromium from the actinides results in a compact, non RCRA secondary waste product.

Wedman, D.E.; Nelson, T.O.; Rivera, Y.; Weisbrod, K.; Martinez, H.E.; Limback, S.

1998-12-31T23:59:59.000Z

Note: This page contains sample records for the topic "aqueous electrolyte modeling" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Method of preparing a sintered lithium aluminate structure for containing electrolyte  

DOE Patents (OSTI)

A porous sintered tile is formed of lithium aluminate for retaining molten lectrolyte within a fuel cell. The tile is prepared by reacting lithium hydroxide in aqueous solution with alumina particles to form beta lithium aluminate particles. The slurry is evaporated to dryness and the solids dehydrated to form a beta lithium aluminate powder. The powder is compacted into the desired shape and sintered at a temperature in excess of 1200 K. but less than 1900 K. to form a porous integral structure that is subsequently filled with molten electrolyte. A tile of this type is intended for use in containing molten alkali metal carbonates as electolyte for use in a fuel cell having porous metal or metal oxide electrodes for burning a fuel gas such as hydrogen and/or carbon monoxide with an oxidant gas containing oxygen.

Sim, James W. (Evergreen Park, IL); Kinoshita, Kimio (Cupertino, CA)

1981-01-01T23:59:59.000Z

262

Stabilization of Nickel Metal Catalysts for Aqueous ...  

Biomass and Biofuels Stabilization of Nickel Metal Catalysts for Aqueous Processing Systems Pacific Northwest National Laboratory.

263

Incorporation of aqueous reaction kinetics and biodegradation into TOUGHREACT: Application of a multi-region model to hydrobiogeoChemical transport of denitrification and sulfate reduction  

E-Print Network (OSTI)

for modeling fluid and heat flow in fractured porous media:1985) for fluid and heat flow in fractured porous media. Theflows of multiphase fluids in porous and fractured media.

Xu, Tianfu

2008-01-01T23:59:59.000Z

264

Incorporation of aqueous reaction kinetics and biodegradation into TOUGHREACT: Application of a multi-region model to hydrobiogeoChemical transport of denitrification and sulfate reduction  

E-Print Network (OSTI)

interplay between Bio- and Chem- Regions will be illustratedThe same A was used for Bio- and Chem- Regions. In fact,1. Concept of a Hydro-Bio-Chem Region model for resolving

Xu, Tianfu

2008-01-01T23:59:59.000Z

265

Method of preparing thin film polymeric gel electrolytes  

DOE Patents (OSTI)

Novel hybrid thin film electrolyte, based on an organonitrile solvent system, which are compositionally stable, environmentally safe, can be produced efficiently in large quantity and which, because of their high conductivities .apprxeq.10.sup.-3 .OMEGA..sup.-1 cm.sup.-1 are useful as electrolytes for rechargeable lithium batteries.

Derzon, Dora K. (Albuquerque, NM); Arnold, Jr., Charles (Albuquerque, NM)

1997-01-01T23:59:59.000Z

266

Magnetic resonance imaging of polymer electrolytes and insertion electrodes.  

DOE Green Energy (OSTI)

This program seeks to better define electrode-electrolyte interfaces and solid-state ion transport mechanisms that are a central feature of fuel cells and advanced electrochemical systems. The goal is to develop a new generation of materials with enhanced energy efficiency and reduced tendency toward dendrite or passive film formation at the electrode-electrolyte interface.

Gerald, R. E., II; Klingler, R. J.; Rathke, J. W.

1999-05-19T23:59:59.000Z

267

PREPARATION AND CHARACTERIZATION OF SOLID ELECTROLYTES: FUEL CELL APPLICATIONS  

DOE Green Energy (OSTI)

The intent of this project with Federal Energy Technology Center (FETC)/Morgantown Energy Technology Center (METC) is to develop research infrastructure conductive to Fuel Cell research at Southern University and A and M College, Baton Route. A state of the art research laboratory (James Hall No.123 and No.114) for energy conversion and storage devices was developed during this project duration. The Solid State Ionics laboratory is now fully equipped with materials research instruments: Arbin Battery Cycling and testing (8 channel) unit, Electrochemical Analyzer (EG and G PAR Model 273 and Solartron AC impedance analyzer), Fuel Cell test station (Globe Tech), Differential Scanning Calorimeter (DSC-10), Thermogravimetric Analyzer (TGA), Scanning Tunneling Microscope (STM), UV-VIS-NIR Absorption Spectrometer, Fluorescence Spectrometer, FT-IR Spectrometer, Extended X-ray Absorption Fine Structure (EXAFS) measurement capability at Center for Advanced Microstructure and Devices (CAMD- a multimillion dollar DOE facility), Glove Box, gas hood chamber, high temperature furnaces, hydraulic press and several high performance computers. IN particular, a high temperature furnace (Thermodyne 6000 furnace) and a high temperature oven were acquired through this project funds. The PI Dr. R Bobba has acquired additional funds from federal agencies include NSF-Academic Research Infrastructure program and other DOE sites. They have extensively used the multimillion dollar DOE facility ''Center'' for Advanced Microstructures and Devices (CAMD) for electrochemical research. The students were heavily involved in the experimental EXAFS measurements and made use of their DCM beamline for EXAFS research. The primary objective was to provide hands on experience to the selected African American undergraduate and graduate students in experimental energy research.The goal was to develop research skills and involve them in the Preparation and Characterization of Solid Electrolytes. Ionically conducting solid electrolytes are successfully used for battery, fuel cell and sensor applications.

Rambabu Bobba; Josef Hormes; T. Wang; Jaymes A. Baker; Donald G. Prier; Tommy Rockwood; Dinesha Hawkins; Saleem Hasan; V. Rayanki

1997-12-31T23:59:59.000Z

268

THERMODYNAMICS OF ELECTROLYTES. X. ENTHALPY AND THE EFFECT OF TEMPERATURE ON THE ACTIVITY COEFFICIENTS.  

E-Print Network (OSTI)

09 THERMODYNAMICS OFELECI'ROLYTES. X'rights. r'-" e. ct THERMODYNAMICS OF ELECTROLYTES. X.Coefficient, Electrolyte, Thermodynamics v ~p , I J ! l

Silvester, Leonard F.

2011-01-01T23:59:59.000Z

269

Preparation of ceramic matrix and alumina fiber composites for use as solid electrolytes  

DOE Patents (OSTI)

A process for making solid electrolytes using a fibrous stabilizing dispersed second phase for enhanced conductivity of the electrolyte after deformation and annealing. 1 tab.

Dudney, N.J.

1987-04-30T23:59:59.000Z

270

Physical Property Modeling of Concentrated Cesium Eluate Solutions, Part I - Derivation of Models  

SciTech Connect

Major analytes projected to be present in the Hanford Waste Treatment Plant cesium ion-exchange eluate solutions were identified from the available analytical data collected during radioactive bench-scale runs, and a test matrix of cesium eluate solutions was designed within the bounding concentrations of those analytes. A computer model simulating the semi-batch evaporation of cesium eluate solutions was run in conjunction with a multi-electrolyte aqueous system database to calculate the physical properties of each test matrix solution concentrated to the target endpoints of 80% and 100% saturation. The calculated physical properties were analyzed statistically and fitted into mathematical expressions for the bulk solubility, density, viscosity, heat capacity and volume reduction factor as a function of temperature and concentration of each major analyte in the eluate feed. The R{sup 2} of the resulting physical property models ranged from 0.89 to 0.99.

Choi, A.S.; Pierce, R. A.; Edwards, T. B.; Calloway, T. B.

2005-09-15T23:59:59.000Z

271

Electrocatalysis issues in polymer electrolyte fuel cells  

DOE Green Energy (OSTI)

Various electrocatalysis issues of impotance to low platinum loading polymer electrolyte fuel cells (PEFCs) are discussed. Thin film catalyst layer assemblies are used to investigate the effects of CO and CO{sub 2} on the anode as well as efforts to restore performance by oxygen bleeding into the anode feedstream. These electrodes behave differently than ionomer-impregnated E-TEK electrodes because the extra, exposed Pt in the latter case. The tolerance of Pt-Ru alloy thin film anodes to CO and CO{sub 2} are also evaluated. Thin film electrodes are also used to study Pt particle growth in aged electrodes as well as particle size effects on specific activity.

Wilson, M.S.; Derouin, C.R.; Valerio, J.A.; Gottesfeld, S.

1993-06-01T23:59:59.000Z

272

Electrocatalysis issues in polymer electrolyte fuel cells  

DOE Green Energy (OSTI)

Various electrocatalysis issues of impotance to low platinum loading polymer electrolyte fuel cells (PEFCs) are discussed. Thin film catalyst layer assemblies are used to investigate the effects of CO and CO[sub 2] on the anode as well as efforts to restore performance by oxygen bleeding into the anode feedstream. These electrodes behave differently than ionomer-impregnated E-TEK electrodes because the extra, exposed Pt in the latter case. The tolerance of Pt-Ru alloy thin film anodes to CO and CO[sub 2] are also evaluated. Thin film electrodes are also used to study Pt particle growth in aged electrodes as well as particle size effects on specific activity.

Wilson, M.S.; Derouin, C.R.; Valerio, J.A.; Gottesfeld, S.

1993-01-01T23:59:59.000Z

273

ELECTROLYTIC OXIDATION OF ZIRCONIUM IN NITRATE SOLUTIONS  

SciTech Connect

Zirconiurn alloys used in the fabrication of nuclear fuel elements can be disintegrated and converted to insoluble oxides by electrolytic treatment in concentrated nitrate solutions. This reaction shows promise as a technique for reprocessing nuclear fuels clad with Zircaloy-2. For a particular applied voltage, nitric acid achieves the highest rate of attack, but the reaction can be carried out at rates of 2 mg/(cm/sup 2/)(min) or greater in either 7.5M sodium nitrate or 2.3M aluminum nitrate. A reaction rate of 7 mg/(cm/sup 2/) (min) can be easily attained in either 8M nitric acid or 7.5M sodium nitrate. The rate of reaction is a function of the temperature and tho applied voltage. An as-yet unsolved problem is the carry--down of uranium with the insoluble zirconium oxide product. (auth)

Bomar, M.R.

1961-12-29T23:59:59.000Z

274

Separators for absorbed electrolyte recombinant batteries  

SciTech Connect

Starved electrolyte gas recombinant batteries are a fast growing segment of the lead-acid market. There is a great deal of development being carried out using the recombinant technology. New batteries of this design have been commercialized this year and more will probably be introduced next year. All of these batteries are sealed so that they can operate above atmospheric pressure, and all of them contain a highly porous, and partially saturated glass microfiber separator. The separator is white, pliable, and ribless. The separator is the key element of these batteries since it permits gas recombination to take place. The recombination of gas within the battery makes it possible to seal the battery. The operation of these batteries is discussed.

Wandzy, K.J.; Taylor, G.W.

1986-07-01T23:59:59.000Z

275

Electrolyte matrix for molten carbonate fuel cells  

DOE Patents (OSTI)

A matrix for a carbonate electrolyte including a support material and an additive constituent having a relatively low melting temperature and a relatively high coefficient of thermal expansion. The additive constituent is from 3 to 45 weight percent of the matrix and is formed from raw particles whose diameter is in a range of 0.1 .mu.m to 20 .mu.m and whose aspect ratio is in a range of 1 to 50. High energy intensive milling is used to mix the support material and additive constituent during matrix formation. Also disclosed is the use of a further additive constituent comprising an alkaline earth containing material. The further additive is mixed with the support material using high energy intensive milling.

Huang, Chao M. (Danbury, CT); Yuh, Chao-Yi (New Milford, CT)

1999-01-01T23:59:59.000Z

276

Electrolyte matrix for molten carbonate fuel cells  

DOE Patents (OSTI)

A matrix is described for a carbonate electrolyte including a support material and an additive constituent having a relatively low melting temperature and a relatively high coefficient of thermal expansion. The additive constituent is from 3 to 45 weight percent of the matrix and is formed from raw particles whose diameter is in a range of 0.1 {micro}m to 20 {micro}m and whose aspect ratio is in a range of 1 to 50. High energy intensive milling is used to mix the support material and additive constituent during matrix formation. Also disclosed is the use of a further additive constituent comprising an alkaline earth containing material. The further additive is mixed with the support material using high energy intensive milling. 5 figs.

Huang, C.M.; Yuh, C.Y.

1999-02-09T23:59:59.000Z

277

Electrolytic production of hydrogen utilizing photovoltaic cells  

DOE Green Energy (OSTI)

Hydrogen has the potential to serve as both an energy storage means and an energy carrier in renewable energy systems. When renewable energy sources such as solar or wind power are used to produce electrical power, the output can vary depending on weather conditions. By using renewable sources to produce hydrogen, a fuel which can be stored and transported, a reliable and continuously available energy supply with a predictable long-term average output is created. Electrolysis is one method of converting renewable energy into hydrogen fuel. In this experiment we examine the use of an electrolyzer based on polymer-electrolyte membrane technology to separate water into hydrogen and oxygen. The oxygen is vented to the atmosphere and the hydrogen is stored in a small pressure vessel.

Daugherty, M.A.

1996-10-01T23:59:59.000Z

278

Electrolytic decontamination of the 3013 inner can  

SciTech Connect

Disposition of plutonium recovered from nuclear weapons or production residues must be stored in a manner that ensures safety. The criteria that has been established to assure the safety of stored materials for a minimum of 50 years is DOE-STD-3013. Los Alamos National Laboratory (LANL) has designed a containment package in accordance with the DOE standard. The package consists of an optional convenience (food pack) can, a welded type 304L stainless steel inner (primary) can, and a welded type 304L stainless steel outer (secondary) can. With or without the food pack can, the material is placed inside the primary can and welded shut under a helium atmosphere. This activity takes place totally within the confinement of the glove box line. Following the welding process, the can is checked for leaks and then sent down the line for decontamination. Once decontaminated, the sealed primary can may be removed from the glove box line. Welding of the secondary container takes place outside the glove box line. The highly automated decontamination process that has been developed to support the packaging of Special Nuclear Materials is based on an electrolytic process similar to the wide spread industrial technique of electropolishing. The can is placed within a specially designed stainless steel fixture built within a partition of a glove box. This fixture is then filled with a flowing electrolyte solution. A low DC electric current is made to flow between the can, acting as the anode, and the fixture, acting as the cathode. Following the decontamination, the system provides a flow of rinse water through the fixture to rinse the can of remaining salt residues. The system then carried out a drying cycle. Finally, the fixture is opened from the opposite side of the partition and the can surface monitored directly and through surface smears to assure that decontamination is adequate.

Wedman, D.E.; Nelson, T.O.; Rivera, Y.; Weisbrod, K.; Martinez, H.E.; Limback, S.

1998-12-31T23:59:59.000Z

279

Ultrafast laser induced breakdown spectroscopy of electrode/electrolyte  

NLE Websites -- All DOE Office Websites (Extended Search)

Ultrafast laser induced breakdown spectroscopy of electrode/electrolyte Ultrafast laser induced breakdown spectroscopy of electrode/electrolyte interfaces Title Ultrafast laser induced breakdown spectroscopy of electrode/electrolyte interfaces Publication Type Journal Article Year of Publication 2012 Authors Zormpa, Vasileia, Jaroslaw Syzdek, Xianglei Mao, Richard E. Russo, and Robert Kostecki Journal Applied Physics Letters Volume 100 Issue 23 Date Published 05-2012 ISSN 0003-6951 Keywords electrochemical electrodes, graphite, high-speed optical techniques, laser beam effects, organic compounds, pyrolysis, solid electrolytes Abstract Direct chemical analysis of electrode/electrolyte interfaces can provide critical information on surface phenomena that define and control the performance of Li-based battery systems. In this work, we introduce the use of ex situ femtosecond laser induced breakdown spectroscopy to probe compositional variations within the solid electrolyte interphase (SEI) layer. Nanometer-scale depth resolution was achieved for elemental and molecular depth profiling of SEI layers formed on highly oriented pyrolytic graphite electrodes in an organic carbonate-based electrolyte. This work demonstrates the unique ability of ultrafast laser spectroscopy as a highly versatile, light element-sensitive technique for direct chemical analysis of interfacial layers in electrochemical energy storage systems.

280

Method of making a layered composite electrode/electrolyte  

DOE Patents (OSTI)

An electrode/electrolyte structure is prepared by a plurality of methods. An unsintered (possibly bisque fired) moderately catalytic electronically-conductive or homogeneous mixed ionic electronic conductive electrode material is deposited on a layer composed of a sintered or unsintered ionically-conductive electrolyte material prior to being sintered. A layer of particulate electrode material is deposited on an unsintered ("green") layer of electrolyte material and the electrode and electrolyte layers are sintered simultaneously, sometimes referred to as "co-firing," under conditions suitable to fully densify the electrolyte while the electrode retains porosity. Or, the layer of particulate electrode material is deposited on a previously sintered layer of electrolyte, and then sintered. Subsequently, a catalytic material is added to the electrode structure by infiltration of an electrolcatalyst precursor (e.g., a metal salt such as a transition metal nitrate). This may be followed by low temperature firing to convert the precursor to catalyst. The invention allows for an electrode with high electronic conductivity and sufficient catalytic activity to achieve high power density in an ionic (electrochemical) device such as fuel cells and electrolytic gas separation systems.

Visco, Steven J. (Berkeley, CA); Jacobson, Craig P. (El Cerrito, CA); DeJonghe, Lutgard C. (Lafayette, CA)

2005-01-25T23:59:59.000Z

Note: This page contains sample records for the topic "aqueous electrolyte modeling" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

RESEARCH AND DEVELOPMENT IN THE FIELD OF THORIUM CHEMISTRY AND METALLURGY. VOLUME I. PREPARATION OF ELECTROLYTIC CELL FEED FOR PRODUCTION OF THORIUM METAL. Final Report  

SciTech Connect

A research and development program in the field of thorium chemistry and metallurgy was conducted. Most of this activity was directed toward the development of techniques for the production of metal by fused salt electrolytic approaches, little effort being proportioned to the preparation of an electrolyte for the process. An aqueous method for the preparation of an anhydrous cell feed was set up and operated for several months. Relatively high operating expense and difficulties with materials of construction prompted the development of a more direct approach for the production of electrolytic cell feed. The system established for cell feed preparation converts thoriumn nitrate to a basic carbonate via the reaction between the nitrate and sodium carbonate, this precipitation being quantitative. Following a suitable filtration and drying operation, the thorium oxycarbonate is converted directly to the chloride by reaction with carbon and chlorine, forming a cell feed containing between 40 and 45% thorium in a molten matrix of sodium and potassium chlorides. The preparation of cell feed by the descrihed process was carried out on a small- tonnage basis, in 1,000-pound batches. The entire process is capable of heing operated on a continuous or semi-continuous basis and presents a commercially feasible approach for the preparation of high quality anhydrous electrolytes suitable for conversion to A.E.C. grade thorium metal by eleetrolytic techniques. A brief description of small-scale research and development experiments leading to the established system also is included. (auth)

Fisher, C.E.; Wyatt, J.L.

1956-06-30T23:59:59.000Z

282

Electrowinning process with electrode compartment to avoid contamination of electrolyte  

DOE Patents (OSTI)

An electrolytic process and apparatus for reducing calcium oxide in a molten electrolyte of CaCl{sub 2}-CaF{sub 2} with a graphite anode in which particles or other contamination from the anode is restricted by the use of a porous barrier in the form of a basket surrounding the anode which may be removed from the electrolyte to burn the graphite particles, and wherein the calcium oxide feed is introduced to the anode compartment to increase the oxygen ion concentration at the anode.

Poa, D.S.; Pierce, R.D.; Mulcahey, T.P.; Johnson, G.K.

1991-12-31T23:59:59.000Z

283

Effect on the Pore-Size Dependence of an Organic Electrolyte Supercapacitor  

Science Conference Proceedings (OSTI)

Organic electrolytes such as tetraethylammonium tetrafluoroborate dissolved in acetonitrile (TEA-BF{sub 4}/ACN) are widely used in commercial supercapacitors and academic research, but conflicting experimental results have been reported regarding the dependence of surface-area-normalized capacitance on the pore size. Here we show from a classical density functional theory the dependence of capacitance on the pore size from 0.5 to 3.0 nm for a model TEA-BF{sub 4}/ACN electrolyte. We find that the capacitance-pore size curve becomes roughly flat after the first peak around the ion diameter, and the peak capacitance is not significantly higher than the large-pore average. We attribute the invariance of capacitance with the pore size to the formation of an electric double-layer structure that consists of counterions and highly organized solvent molecules. This work highlights the role of the solvent molecules in modulating the capacitance and reconciles apparently conflicting experimental reports.

Jiang, Deen [ORNL; Jin, Zhehui [University of California, Riverside; Henderson, Douglous [Brigham Young University; Wu, Jianzhong [University of California, Riverside

2012-01-01T23:59:59.000Z

284

Thermodynamic Model for SnO2(cr) and SnO2(am) Solubility in the Aqueous Na+-H+ -OH- -Cl- -H2O System  

SciTech Connect

The solubility of SnO2(cassiterite) was studied at 23 ? 2?C as functions of time (7 – 49 days) and pH value (0-14.5). Steady state concentrations were reached in < 7 days. The data were interpreted using the SIT model. The data shows that SnO2(cassiterite) is the stable phase at pH values of < ~11.7. These extensive data provided a log10 K0 value of -64.39 ± 0.30 for the reaction (SnO2(cassiterite) + 2H2O = Sn4+ + 4OH-) and values of 1.86 ± 0.30, ? -0.62, -9.20 ± 0.34, and -20.28 ± 0.34 for the reaction (Sn4+ + nH2O = Sn(OH)n4-n + nH+) with values of “n” equal to 1, 4, 5, and 6 respectively. These thermodynamic hydrolysis constants were used to reinterpret the extensive literature data for SnO2(am) solubility, which provided a log10 K0 value of -61.80 ± 0.29 for the reaction (SnO2(am) + 2H2O = Sn4+ + 4OH-). SnO2(cassiterite) is unstable under highly alkaline conditions (NaOH concentrations > 0.003 mol.dm-3) and transforms to a double salt of SnO2 and NaOH. Although additional well-focused studies will be required for confirmation, the experimental data in the highly alkaline region (0.003 to 3.5 mol.dm-3 NaOH) can be well described with log10 K0 of -5.29 ± 0.35 for the reaction (Na2Sn(OH)6(s) = Na2Sn(OH)6(aq)).

Rai, Dhanpat; Yui, Mikazu; Schaef, Herbert T.; Kitamura, Akira

2011-08-01T23:59:59.000Z

285

Method of preparing electrolyte for use in fuel cells  

DOE Patents (OSTI)

An electrolyte compact for fuel cells includes a particulate support material of lithium aluminate that contains a mixture of alkali metal compounds, such as carbonates or hydroxides, as the active electrolyte material. The porous lithium aluminate support structure is formed by mixing alumina particles with a solution of lithium hydroxide and another alkali metal hydroxide, evaporating the solvent from the solution and heating to a temperature sufficient to react the lithium hydroxide with alumina to form lithium aluminate. Carbonates are formed by reacting the alkali metal hydroxides with carbon dioxide gas in an exothermic reaction which may proceed simultaneously with the formation with the lithium aluminate. The mixture of lithium aluminate and alkali metal in an electrolyte active material is pressed or otherwise processed to form the electrolyte structure for assembly into a fuel cell.

Kinoshita, Kimio (Downers Grove, IL); Ackerman, John P. (Downers Grove, IL)

1978-01-01T23:59:59.000Z

286

High temperature solid electrolyte fuel cell configurations and interconnections  

DOE Patents (OSTI)

High temperature fuel cell configurations and interconnections are made including annular cells having a solid electrolyte sandwiched between thin film electrodes. The cells are electrically interconnected along an elongated axial outer surface.

Isenberg, Arnold O. (Forest Hills, PA)

1984-01-01T23:59:59.000Z

287

Polymer electrolytes for a rechargeable li-Ion battery  

SciTech Connect

Lithium-ion polymer electrolyte battery technology is attractive for many consumer and military applications. A Li{sub x}C/Li{sub y}Mn{sub 2}O{sub 4} battery system incorporating a polymer electrolyte separator base on novel Li-imide salts is being developed under sponsorship of US Army Research Laboratory (Fort Monmouth NJ). This paper reports on work currently in progress on synthesis of Li-imide salts, polymer electrolyte films incorporating these salts, and development of electrodes and cells. A number of Li salts have been synthesized and characterized. These salts appear to have good voltaic stability. PVDF polymer gel electrolytes based on these salts have exhibited conductivities in the range 10{sup -4} to 10{sub -3} S/cm.

Argade, S.D.; Saraswat, A.K.; Rao, B.M.L. [Technochem Co., Greensboro, NC (United States); Lee, H.S.; Xiang, C.L.; McBreen, J. [Brookhaven National Lab., Upton, NY (United States)

1996-10-01T23:59:59.000Z

288

Technoeconomic Evaluation of Large-Scale Electrolytic Hydrogen Production Technologies  

Science Conference Proceedings (OSTI)

Large-scale production of electrolytic hydrogen and oxygen could increase use of baseload and off-peak surplus power. To be competitive, however, water electrolysis will require low-cost electricity.

1985-09-20T23:59:59.000Z

289

Molten salt electrolyte battery cell with overcharge tolerance  

SciTech Connect

A molten salt electrolyte battery having an increased overcharge tolerance employs a negative electrode with two lithium alloy phases of different electrochemical potential, one of which allows self-discharge rates which permits battery cell equalization.

Kaun, Thomas D. (New Lenox, IL); Nelson, Paul A. (Wheaton, IL)

1989-01-01T23:59:59.000Z

290

Success Stories: Solid Electrolyte Lithium Ion Batteries - Seeo, Inc.  

NLE Websites -- All DOE Office Websites (Extended Search)

Solid Electrolyte May Usher in a New Generation of Solid Electrolyte May Usher in a New Generation of Rechargeable Lithium Batteries For Vehicles With sky rocketing gasoline prices and exploding laptops, there could not have been a better time for a new rechargeable battery breakthrough. Enter Lawrence Berkeley National Laboratory's (LBNL) nanostructured polymer electrolyte (NPE). NPE is a solid electrolyte designed for use in rechargeable lithium batteries. The unique material was developed by LBNL researchers Nitash Balsara, Hany Eitouni, Enrique Gomez, and Mohit Singh and licensed to startup company Seeo Inc. in 2007. With solid financial backing from Khosla Ventures, located in Menlo Park, California, and an impressive scientific team recruited from LBNL, University of California, Berkeley, and the battery industry, Seeo is now

291

Electrolytic cell. [operation at 500,000 amperes  

SciTech Connect

A novel electrolytic cell of the vertical electrode type comprising a novel cathode busbar structure, novel cathode elements and a novel anode base structure which enable the novel electrolytic cell to be designed to operate at high current capacities upward to about 500,000 amperes while maintaining high operating efficiencies is claimed. These high current capacities provide for high production capacities which result in high production rates for given cell room floor areas and reduce capital investment and operating costs.

Mose, L.; Kramer, W.; Strewe, W.; Strasser, B.

1977-04-12T23:59:59.000Z

292

Non-aqueous solution preparation of doped and undoped Li{sub x}Mn{sub y}O{sub z}  

DOE Patents (OSTI)

A method is described for generation of phase-pure doped and undoped Li{sub x}Mn{sub y}O{sub z} precursors. The method of this invention uses organic solutions instead of aqueous solutions or nonsolution ball milling of dry powders to produce phase-pure precursors. These precursors can be used as cathodes for lithium-polymer electrolyte batteries. Dopants may be homogeneously incorporated to alter the characteristics of the powder. 1 fig.

Boyle, T.J.; Voigt, J.A.

1997-05-20T23:59:59.000Z

293

Effects of Nonaqueous Electrolytes on Primary Li-Air Batteries  

SciTech Connect

The effects of nonaqueous electrolytes on the performance of primary Li-air batteries operated in dry air environment have been investigated. Organic solvents with low volatility and low moisture absorption are necessary to minimize the change of electrolyte compositions and the reaction between Li anode and water during the discharge process. The polarity of aprotic solvents outweighs the viscosity, ion conductivity and oxygen solubility on the performance of Li-air batteries once these latter properties attain certain reasonable level, because the solvent polarity significantly affects the number of tri-phase regions formed by oxygen, electrolyte, and active carbons (with catalyst) in the air electrode. The most feasible electrolyte formulation is the system of LiTFSI in PC/EC mixtures, whose performance is relatively insensitive to PC/EC ratio and salt concentration. The quantity of such electrolyte added to a Li-air cell has notably effects on the discharge performance of the Li-air battery as well, and a maximum in capacity is observed as a function of electrolyte amount. The coordination effect from the additives or co-solvents [tris(pentafluorophenyl)borane and crown ethers in this study] also greatly affects the discharge performance of a Li-air battery.

Xu, Wu; Xiao, Jie; Wang, Deyu; Zhang, Jian; Zhang, Jiguang

2010-06-14T23:59:59.000Z

294

Polymer electrolyte fuel cells for transportation applications  

DOE Green Energy (OSTI)

The application of the polymer electrolyte fuel cell (PEFC) as a primary power source in electric vehicles has received incrming attention during the last few years. This increased attention has been fueled by a combination of significant technical advances in this field and by the initiation of some projects for the demonstration of a complete, PEFC-based power system in a bus or in a passenger car. Such demonstration pretieds reflect an increased faith of industry in the potential of this technology for transportation applications, or, at least, in the need for a detailed evaluation of this potential Nevertheless, large scale transportation applications of PEFCs requim a continued concerted effort of research on catalysis, materials and components, combined with the engineering efforts addressing the complete power system. This is required to achieve cost effective, highly performing PEFC stack and power system. We describe in this contribution some recent results of work performed within the Core Research PEFC Program at Los Alamos National Laboratory, which has addressed transportation applications of PEFCs.

Springer, T.E.; Wilson, M.S.; Garzon, F.H.; Zawodzinski, T.A.; Gottesfeld, S.

1993-01-01T23:59:59.000Z

295

Polymer electrolyte fuel cells for transportation applications  

DOE Green Energy (OSTI)

The application of the polymer electrolyte fuel cell (PEFC) as a primary power source in electric vehicles has received incrming attention during the last few years. This increased attention has been fueled by a combination of significant technical advances in this field and by the initiation of some projects for the demonstration of a complete, PEFC-based power system in a bus or in a passenger car. Such demonstration pretieds reflect an increased faith of industry in the potential of this technology for transportation applications, or, at least, in the need for a detailed evaluation of this potential Nevertheless, large scale transportation applications of PEFCs requim a continued concerted effort of research on catalysis, materials and components, combined with the engineering efforts addressing the complete power system. This is required to achieve cost effective, highly performing PEFC stack and power system. We describe in this contribution some recent results of work performed within the Core Research PEFC Program at Los Alamos National Laboratory, which has addressed transportation applications of PEFCs.

Springer, T.E.; Wilson, M.S.; Garzon, F.H.; Zawodzinski, T.A.; Gottesfeld, S.

1993-03-01T23:59:59.000Z

296

Capillary, wettability and interfacial dynamics in polymer electrolyte fuel cells  

SciTech Connect

In the present scenario of a global initiative toward a sustainable energy future, the polymer electrolyte fuel cell (PEFC) has emerged as one of the most promising alternative energy conversion devices for different applications. Despite tremendous progress in recent years, a pivotal performance/durability limitation in the PEFC arises from liquid water transport, perceived as the Holy Grail in PEFC operation. The porous catalyst layer (CL), fibrous gas diffusion layer (GDL) and flow channels play a crucial role in the overall PEFC performance due to the transport limitation in the presence of liquid water and flooding phenomena. Although significant research, both theoretical and experimental, has been performed, there is serious paucity of fundamental understanding regarding the underlying structure-transport-performance interplay in the PEFC. The inherent complex morphologies, micro-scale transport physics involving coupled multiphase, multicomponent, electrochemically reactive phenomena and interfacial interactions in the constituent components pose a formidable challenge. In this paper, the impact of capillary transport, wetting characteristics and interfacial dynamics on liquid water transport is presented based on a comprehensive mesoscopic modeling framework with the objective to gain insight into the underlying electrodynamics, two-phase dynamics and the intricate structure-transport-interface interactions in the PEFC.

Mukherjee, Partha P [Los Alamos National Laboratory

2009-01-01T23:59:59.000Z

297

Dense gas dispersion modeling for aqueous releases.  

E-Print Network (OSTI)

??Production, transportation, and storage of hazardous chemicals represent potential risks to the environment, the public, and the producers themselves. The release to the atmosphere of… (more)

Lara, Armando

2012-01-01T23:59:59.000Z

298

Inverse hydrochemical models of aqueous extracts tests  

E-Print Network (OSTI)

method to estimate porewater chemical composition of clays. Main uncertainties are related to kinetic calcite dissolution and

Zheng, L.

2010-01-01T23:59:59.000Z

299

Solar-assisted hydrogen generation by photoelectrocatalysis: electric birefringence and ellipsometric spectroscopy of the semiconductor/electrolyte interface. Annual report 3 Sep 82-31 Aug 83  

SciTech Connect

The project goals are to apply and develop electro-optical techniques (electric birefringence and ellipsometric spectroscopy) for in-situ investigation of modified and unmodified photoelectrode/liquid junctions. This information will be used in conjunction with other spectroscopic and photoelectro-chemical techniques to delineate those features, necessary at this interface, for the achievement of high photo-electrolysis efficiencies. The thorough understanding obtained for both the photoelectrode and its liquid junction with aqueous electrolytes will be directed toward the development of high-efficiency photo-electrochemical cells for hydrogen generation.

Ang, P.G.P.; St. John, M.R.; Sammells, A.F.

1983-09-01T23:59:59.000Z

300

Physical Properties Models for Simulation of Processes to Treat INEEL Tank Farm Waste: Thermodynamic Equilibrium  

SciTech Connect

A status is presented of the development during FY2002 of a database for physical properties models for the simulation of the treatment of Sodium-Bearing Waste (SBW) at the Idaho National Engineering and Environmental Laboratory. An activity coefficient model is needed for concentrated, aqueous, multi-electrolyte solutions that can be used by process design practitioners. Reasonable first-order estimates of activity coefficients in the relevant media are needed rather than an incremental improvement in theoretical approaches which are not usable by practitioners. A comparison of the Electrolyte Non-Random Two-Liquid (ENRTL) and Pitzer ion-interaction models for the thermodynamic representation of SBW is presented. It is concluded that Pitzer's model is superior to ENRTL in modeling treatment processes for SBW. The applicability of the Pitzer treatment to high concentrations of pertinent species and to the determination of solubilities and chemical equilibria is addressed. Alternate values of Pitzer parameters for HCl, H2SO4, and HNO3 are proposed, applicable up to 16m, and 12m, respectively. Partial validation of the implementation of Pitzer's treatment within the commercial process simulator ASPEN Plus was performed.

Nichols, T.T.; Taylor, D.D.

2002-07-18T23:59:59.000Z

Note: This page contains sample records for the topic "aqueous electrolyte modeling" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Physical Properties Models for Simulation of Processes to Treat INEEL Tank Farm Waste: Thermodynamic Equilibrium  

SciTech Connect

A status is presented of the development during FY2002 of a database for physical properties models for the simulation of the treatment of Sodium-Bearing Waste (SBW) at the Idaho National Engineering and Environmental Laboratory. An activity coefficient model is needed for concentrated, aqueous, multi-electrolyte solutions that can be used by process design practitioners. Reasonable first-order estimates of activity coefficients in the relevant media are needed rather than an incremental improvement in theoretical approaches which are not usable by practitioners. A comparison of the Electrolyte Non-Random Two-Liquid (ENRTL) and Pitzer ion-interaction models for the thermodynamic representation of SBW is presented. It is concluded that Pitzer's model is superior to ENRTL in modeling treatment processes for SBW. The applicability of the Pitzer treatment to high concentrations of pertinent species and to the determination of solubilities and chemical equilibria is addressed. Alternate values of Pitzer parameters for HCl, H2SO4, and HNO3 are proposed, applicable up to 16m, and 12m, respectively. Partial validation of the implementation of Pitzer's treatment within the commercial process simulator ASPEN Plus was performed.

Nichols, Todd Travis; Taylor, Dean Dalton

2002-07-01T23:59:59.000Z

302

Study of Electrolyte Impurity Precipitates at the Kennecott Refinery  

Science Conference Proceedings (OSTI)

Biosorption Characteristics of Pb(II) from Aqueous Solution onto Poplar Cotton · Characterization of Aluminum Cathode Sheets Used for Zinc Electrowinning.

303

[Polymer-in-salt electrolytes]. Annual report and extension proposal  

DOE Green Energy (OSTI)

The research proposed for the current grant consisted of five components, of which the authors have made substantial progress on three and have performed some exploratory work on a sixth for which they present here an argument for extending. The components on which they have made progress are: (1) development of and improvement on the basic polymer-in-salt idea. This will be separated into parts dealing with improvements in salt constitution, and improvements in polymer type, emphasizing the role of anionic polymers; (2) modifications of the polymer-in-salt electrolyte to include the addition of solid particulates to the salt-polymer matrix; and (3) physical measurements. The new component on which they have made some preliminary measurements over the summer period concerns the use of electrolytes developed under the present and other programs for improving the performance of photovoltaic cells. The rationale is that hole/electron separation in semiconductors under irradiation is aided by trapping the holes on a redox species in an adjacent electrolyte solution. The efficiency is proportional to a number of factors not fully understood, one of which is determined by the character of the electrolyte. Since the authors have new types of electrolytes under development, and since solar energy via photovoltaic is an environmentally important aspect of the energy sciences, they felt it was a desirable aspect of materials science to study in a laboratory in Arizona. Achievements in the past year are summarized.

Angell, C.A.

1998-12-31T23:59:59.000Z

304

Bath for electrolytic reduction of alumina and method therefor  

SciTech Connect

An electrolytic bath for use during the electrolytic reduction of alumina to aluminum. The bath comprises a molten electrolyte having the following ingredients: (a) AlF.sub.3 and at least one salt selected from the group consisting of NaF, KF, and LiF; and (b) about 0.004 wt. % to about 0.2 wt. %, based on total weight of the molten electrolyte, of at least one transition metal or at least one compound of the metal or both. The compound may be, for example, a fluoride, oxide, or carbonate. The metal can be nickel, iron, copper, cobalt, or molybdenum. The bath can be employed in a combination that includes a vessel for containing the bath and at least one non-consumable anode and at least one dimensionally stable cathode in the bath. Employing the bath of the present invention during electrolytic reduction of alumina to aluminum can improve the wetting of aluminum on a cathode by reducing or eliminating the formation of non-metallic deposits on the cathode.

Brown, Craig W. (Seattle, WA); Brooks, Richard J. (Seattle, WA); Frizzle, Patrick B. (Lynnwood, WA); Juric, Drago D. (Bulleen, AU)

2001-07-10T23:59:59.000Z

305

Bath for electrolytic reduction of alumina and method therefor  

DOE Patents (OSTI)

An electrolytic bath for use during the electrolytic reduction of alumina to aluminum. The bath comprises a molten electrolyte having the following ingredients: (a) AlF.sub.3 and at least one salt selected from the group consisting of NaF, KF, and LiF; and (b) about 0.004 wt. % to about 0.2 wt. %, based on total weight of the molten electrolyte, of at least one transition metal or at least one compound of the metal or both. The compound may be, for example, a fluoride, oxide, or carbonate. The metal can be nickel, iron, copper, cobalt, or molybdenum. The bath can be employed in a combination that includes a vessel for containing the bath and at least one non-consumable anode and at least one dimensionally stable cathode in the bath. Employing the bath of the present invention during electrolytic reduction of alumina to aluminum can improve the wetting of aluminum on a cathode by reducing or eliminating the formation of non-metallic deposits on the cathode. Removing sulfur from the bath can also minimize cathode deposits. Aluminum formed on the cathode can be removed directly from the cathode.

Brown, Craig W. (Seattle, WA); Brooks, Richard J. (Seattle, WA); Frizzle, Patrick B. (Lynnwood, WA); Juric, Drago D. (Bulleen, AU)

2002-11-26T23:59:59.000Z

306

Nickel-hydrogen battery with oxygen and electrolyte management features  

SciTech Connect

A nickel-hydrogen battery or cell having one or more pressure vessels containing hydrogen gas and a plurality of cell-modules therein. Each cell-module includes a configuration of cooperatively associated oxygen and electrolyte mangement and component alignment features. A cell-module having electrolyte includes a negative electrode, a positive electrode adapted to facilitate oxygen diffusion, a separator disposed between the positive and negative electrodes for separating them and holding electrolyte for ionic conductivity, an absorber engaging the surface of the positive electrode facing away from the separator for providing electrolyte to the positive electrode, and a pair of surface-channeled diffusion screens for enclosing the positive and negative electrodes, absorber, and separator and for maintaining proper alignment of these components. The screens, formed in the shape of a pocket by intermittently sealing the edges together along as many as three sides, permit hydrogen gas to diffuse therethrough to the negative electrodes, and prevent the edges of the separator from swelling. Electrolyte is contained in the cell-module, absorbhed by the electrodes, the separator and the absorber.

Sindorf, John F. (Pewaukee, WI)

1991-10-22T23:59:59.000Z

307

A Simulation Study of the Lithium Ion Transport Mechanism in Ternary Polymer Electrolytes - The Critical Role of the Segmental Mobility  

E-Print Network (OSTI)

We present an extensive molecular dynamics (MD) simulation study of the lithium ion transport in ternary polymer electrolytes consisting of poly(ethylene oxide) (PEO), lithium-bis(trifluoromethane)sulfonimide (LiTFSI) and the ionic liquid N-methyl-N-propylpyrrolidinium bis(trifluoromethane)sulfonimide (PYR13TFSI). In particular, we focus on two different strategies by which the ternary electrolytes can be devised, namely by (a) adding the ionic liquid to PEO20LiTFSI, and (b) substituting the PEO chains in PEO20LiTFSI by the ionic liquid. In order to grasp the changes of the overall lithium transport mechanism, we employ an analytical, Rouse-based cation transport model (Maitra et al., Phys. Rev. Lett., 2007, 98, 227802), which has originally been devised for binary PEO-based electrolytes. This model distinguishes three different microscopic transport mechanisms, each quantified by an individual time scale. In the course of our analysis, we extend this mathematical description to account for an entirely new transport mechanism, namely the TFSI-supported diffusion of lithium ions decoupled from the PEO chains, which emerges for certain stoichiometries. We find that the segmental mobility plays a decisive role in PEO-based polymer electrolytes. That is, whereas the addition of the ionic liquid to PEO20LiTFSI plasticizes the polymer network and thus also increases the lithium diffusion, the amount of free, mobile ether oxygens reduces when substituting the PEO chains by the ionic liquid, which compensates the plasticizing effect. In total, our observations allow us to formulate some general principles about the lithium ion transport mechanism in ternary polymer electrolytes. Moreover, our insights also shed light on recent experimental observations (Joost et al., Electrochim. Acta, 2012, 86, 330).

Diddo Diddens; Andreas Heuer

2012-11-14T23:59:59.000Z

308

Fuel cell and system for supplying electrolyte thereto with wick feed  

DOE Patents (OSTI)

An electrolyte distribution and supply system for use with a fuel cell having a means for drawing electrolyte therein is formed by a set of containers of electrolyte joined to respective fuel cells in a stack of such cells. The electrolyte is separately stored so as to provide for electrical isolation between electrolytes of the individual cells of the stack. Individual storage compartments are coupled by tubes containing wicking fibers, the ends of the respective tubes terminating on the means for drawing electrolyte in each of the respective fuel cells. Each tube is heat shrunk to tightly bind the fibers therein.

Cohn, J. Gunther (West Orange, NJ); Feigenbaum, Haim (Highland Park, NJ); Kaufman, Arthur (West Orange, NJ)

1984-01-01T23:59:59.000Z

309

Statistical mechanics of sum frequency generation spectroscopy for the liquid-vapor interface of dilute aqueous salt solutions  

SciTech Connect

We demonstrate a theoretical description of vibrational sum frequency generation (SFG) at the boundary of aqueous electrolyte solutions. This approach identifies and exploits a simple relationship between SFG lineshapes and the statistics of molecular orientation and electric field. Our computer simulations indicate that orientational averages governing SFG susceptibility do not manifest ion-specific shifts in local electric field, but instead, ion-induced polarization of subsurface layers. Counterbalancing effects are obtained for monovalent anions and cations at the same depth. Ions held at different depths induce an imbalanced polarization, suggesting that ion-specific effects can arise from weak, long ranged influence on solvent organization.

Noah-Vanhoucke, Joyce; Smith, Jared D.; Geissler, Phillip L.

2009-01-02T23:59:59.000Z

310

Hydrogen & Fuel Cells - Fuel Cell - Polymer Electrolyte  

NLE Websites -- All DOE Office Websites (Extended Search)

Polymer Electrolyte Fuel Cell Research Polymer Electrolyte Fuel Cell Research Xiaoping Wang measures the stability of a platinum cathode electrocatalyst. Xiaoping Wang measures the stability of a platinum cathode electrocatalyst. One of the main barriers to the commercialization of polymer electrolyte fuel cell (PEFC) systems, especially for automotive use, is the high cost of the platinum electrocatalysts. Aside from the cost of the precious metal, concern has also been raised over the adequacy of the world supply of platinum, if fuel cell vehicles were to make a significant penetration into the global automotive fleet. At Argonne, chemists are working toward the development of low-cost nonplatinum electrocatalysts for the oxygen reduction reaction--durable materials that would be stable in the fuel

311

Lithium sulfide compositions for battery electrolyte and battery electrode coatings  

Science Conference Proceedings (OSTI)

Methods of forming lithium-containing electrolytes are provided using wet chemical synthesis. In some examples, the lithium containing electroytes are composed of .beta.-Li.sub.3PS.sub.4 or Li.sub.4P.sub.2S.sub.7. The solid electrolyte may be a core shell material. In one embodiment, the core shell material includes a core of lithium sulfide (Li.sub.2S), a first shell of .beta.-Li.sub.3PS.sub.4 or Li.sub.4P.sub.2S.sub.7, and a second shell including one or .beta.-Li.sub.3PS.sub.4 or Li.sub.4P.sub.2S.sub.7 and carbon. The lithium containing electrolytes may be incorporated into wet cell batteries or solid state batteries.

Liang, Chengdu; Liu, Zengcai; Fu, Wunjun; Lin, Zhan; Dudney, Nancy J; Howe, Jane Y; Rondinone, Adam J

2013-12-03T23:59:59.000Z

312

Fe/V Redox Flow Battery Electrolyte Investigation and Optimization  

Science Conference Proceedings (OSTI)

Recently invented Fe/V redox flow battery (IVBs) system has attracted more and more attentions due to its long-term cycling stability. In this paper, the factors (such as compositions, state of charge (SOC) and temperatures) influencing the stability of electrolytes in both positive and negative half-cells were investigated by an extensive matrix study. Thus an optimized electrolyte, which can be operated in the temperature ranges from -5oC to 50oC without any precipitations, was identified. The Fe/V flow cells using the optimized electrolytes and low-cost membranes exhibited satisfactory cycling performances at different temperatures. The efficiencies, capacities and energy densities of flow batteries with varying temperatures were discussed in detail.

Li, Bin; Li, Liyu; Wang, Wei; Nie, Zimin; Chen, Baowei; Wei, Xiaoliang; Luo, Qingtao; Yang, Zhenguo; Sprenkle, Vincent L.

2013-05-01T23:59:59.000Z

313

Electrolytic decontamination of conductive materials for hazardous waste management  

SciTech Connect

Electrolytic removal of plutonium and americium from stainless steel and uranium surfaces has been demonstrated. Preliminary experiments were performed on the electrochemically based decontamination of type 304L stainless steel in sodium nitrate solutions to better understand the metal removal effects of varying cur-rent density, pH, and nitrate concentration parameters. Material removal rates and changes in surface morphology under these varying conditions are reported. Experimental results indicate that an electropolishing step before contamination removes surface roughness, thereby simplifying later electrolytic decontamination. Sodium nitrate based electrolytic decontamination produced the most uniform stripping of material at low to intermediate pH and at sodium nitrate concentrations of 200 g L{sup -1} and higher. Stirring was also observed to increase the uniformity of the stripping process.

Wedman, D.E.; Martinez, H.E.; Nelson, T.O.

1996-12-31T23:59:59.000Z

314

Elucidating through-plane liquid water profile in a polymer electrolyte membrane fuel cell.  

DOE Green Energy (OSTI)

In this paper, a numerical model incorporating micro-porous layers (MPLs) is presented for simulating water transport within the gas diffusion layers (GDLs) and MPLs as well as across their interfaces in a polymer electrolyte membrane (PEM) fuel cell. One-dimensional analysis is conducted to investigate the impacts of MPL and GDL properties on the liquid-water profile across the anode GDL-MPL and cathode MPL-GDL regions. Furthermore, two-dimensional numerical simulations that take MPLs into account are also carried out to elucidate liquid water transport, particularly through-plane liquid-water profile in a PEM fuel cell. Results from case studies are presented.

Wang, Yun (University of California, Irvine, CA); Chen, Ken Shuang

2010-10-01T23:59:59.000Z

315

Proton conduction in electrolyte made of manganese dioxide for hydrogen gas sensor  

DOE Green Energy (OSTI)

We propose a network model of oxygen-pairs to store and conduct protons on the surface of manganese dioxide with a weak covalent bond like protons stored in pressured ice. The atomic distances of oxygen-pairs were estimated between 2.57 and 2.60 angstroms in crystal structures of ramsdellite-type and lambda-type manganese dioxides by using protonated samples and inelastic neutron scattering measurements. Good properties for a hydrogen gas sensor using electrolytes made of manganese dioxides that contain such oxygen-pairs were confirmed experimentally.

Koyanaka, Hideki [Kyoto University, Japan; Ueda, Yoshikatsu [Kyoto University, Japan; Takeuchi, K [Tokyo University of Science, Oshamanbe Hokkaido, Japan; Kolesnikov, Alexander I [ORNL

2012-01-01T23:59:59.000Z

316

Components and materials issues in polymer electrolyte fuel cells for transportation applications  

DOE Green Energy (OSTI)

Recent research work on the polymer electrolyte fuel cell (PEFC) is described. This research work addresses the goal of bringing the PEFC technology to the performance and the cost levels required for its wide spread use in transportation. The main topics are (a) a new approach to the fabrication of Pt/C catalyst layers of high performance, employing loadings as low as 0.1 mgPt/cm{sup 2}; (b) measurements and modeling of membrane, cathode catalyst and cathode backing contributions to cell loses in the PEFC; and (c) carbon monoxide poisoning of anode electrocatalysts in the PEFC -- the problem and possible solutions. 13 refs.

Derouin, C.R.; Springer, T.E.; Uribe, F.A.; Valerio, J.A.; Wilson, M.S.; Zawodzinski, T.A.; Gottesfeld, S.

1992-01-01T23:59:59.000Z

317

Aqueous Chemical Growth of Advanced Nanostructured ... - TMS  

Science Conference Proceedings (OSTI)

Feb 1, 2002 ... A novel concept in materials chemistry have been developed as well as an aqueous low temperature thin film growth technique to create a new ...

318

Determination of optimum electrolyte composition for molten carbonate fuel cells  

DOE Green Energy (OSTI)

The objective of this study is to determine the optimum electrolyte composition for molten carbonate fuel cells. To accomplish this, the contractor will provide: (1) Comprehensive reports of on-going efforts to optimize carbonate composition. (2) A list of characteristics affected by electrolyte composition variations (e.g. ionic conductivity, vapor pressure, melting range, gas solubility, exchange current densities on NiO, corrosion and cathode dissolution effects). (3) Assessment of the overall effects that these characteristics have on state-of-the-art cell voltage and lifetime.

Yuh, C.Y.; Pigeaud, A.

1987-01-01T23:59:59.000Z

319

Fuel cell system with separating structure bonded to electrolyte  

DOE Patents (OSTI)

A fuel cell assembly comprises a separating structure configured for separating a first reactant and a second reactant wherein the separating structure has an opening therein. The fuel cell assembly further comprises a fuel cell comprising a first electrode, a second electrode, and an electrolyte interposed between the first and second electrodes, and a passage configured to introduce the second reactant to the second electrode. The electrolyte is bonded to the separating structure with the first electrode being situated within the opening, and the second electrode being situated within the passage.

Bourgeois, Richard Scott (Albany, NY); Gudlavalleti, Sauri (Albany, NY); Quek, Shu Ching (Clifton Park, NY); Hasz, Wayne Charles (Pownal, VT); Powers, James Daniel (Santa Monica, CA)

2010-09-28T23:59:59.000Z

320

Sealed absorbed electrolyte battery with bulge compensating end cells  

Science Conference Proceedings (OSTI)

A sealed absorbed electrolyte battery is described comprising, in combination: a sealed container divided into working cells by internal partition walls; each working cell containing an electrode stack comprising positive and negative plates and substantially porous separators intimately contacting and separating the positive and negative plates; an electrolyte substantially completely absorbed in the plates and separators; the working cells being dimensioned to hold the plates and separators within the working cell in contact with each other; and bulge compensating auxiliary cells for accommodating gas pressure changes within the battery without substantially deforming the working cells.

Oswald, T.L.

1988-03-08T23:59:59.000Z

Note: This page contains sample records for the topic "aqueous electrolyte modeling" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Porous electrolyte retainer for molten carbonate fuel cell. [lithium aluminate  

DOE Patents (OSTI)

A porous tile for retaining molten electrolyte within a fuel cell is prepared by sintering particles of lithium aluminate into a stable structure. The tile is assembled between two porous metal plates which serve as electrodes with fuels gases such as H/sub 2/ and CO opposite to oxidant gases such as O/sub 2/ and CO/sub 2/. The tile is prepared with a porosity of 55 to 65% and a pore size distribution selected to permit release of sufficient molten electrolyte to wet but not to flood the adjacent electrodes.

Singh, R.N.; Dusek, J.T.

1979-12-27T23:59:59.000Z

322

Recent advances in solid polymer electrolyte fuel cell technology  

DOE Green Energy (OSTI)

With methods used to advance solid polymer electrolyte fuel cell technology, we are close to obtaining the goal of 1 A/cm/sup 2/ at 0.7. Higher power densities have been reported (2 A/cm/sup 2/ at 0.5 V) but only with high catalyst loading electrodes (2 mg/cm/sup 2/ and 4 mg/cm/sup 2/ at anode and cathode, respectively) and using a Dow membrane with a better conductivity and water retention characteristics. Work is in progress to ascertain performances of cells with Dow membrane impregnated electrodes and Dow membrane electrolytes. 5 refs., 6 figs.

Ticianelli, E.A.; Srinivasan, S.; Gonzalez, E.R.

1988-01-01T23:59:59.000Z

323

Process to remove rare earth from IFR electrolyte  

DOE Patents (OSTI)

The invention is a process for the removal of rare earths from molten chloride electrolyte salts used in the reprocessing of integrated fast reactor fuel (IFR). The process can be used either continuously during normal operation of the electrorefiner or as a batch process. The process consists of first separating the actinide values from the salt before purification by removal of the rare earths. After replacement of the actinides removed in the first step, the now-purified salt electrolyte has the same uranium and plutonium concentration and ratio as when the salt was removed from the electrorefiner.

Ackerman, John P. (Downers Grove, IL); Johnson, Terry R. (Wheaton, IL)

1994-01-01T23:59:59.000Z

324

Process to remove rare earth from IFR electrolyte  

DOE Patents (OSTI)

The invention is a process for the removal of rare earths from molten chloride electrolyte salts used in the reprocessing of integrated fast reactor fuel (IFR). The process can be used either continuously during normal operation of the electrorefiner or as a batch process. The process consists of first separating the actinide values from the salt before purification by removal of the rare earths. After replacement of the actinides removed in the first step, the now-purified salt electrolyte has the same uranium and plutonium concentration and ratio as when the salt was removed from the electrorefiner. 1 fig.

Ackerman, J.P.; Johnson, T.R.

1994-08-09T23:59:59.000Z

325

Process to remove rare earth from IFR electrolyte  

DOE Patents (OSTI)

The invention is a process for the removal of rare earths from molten chloride electrolyte salts used in the reprocessing of integrated fast reactor fuel (IFR). The process can be used either continuously during normal operation of the electrorefiner or as a batch process. The process consists of first separating the actinide values from the salt before purification by removal of the rare earths. After replacement of the actinides removed in the first step, the now-purified salt electrolyte has the same uranium and plutonium concentration and ratio as when the salt was removed from the electrorefiner.

Ackerman, J.P.; Johnson, T.R.

1992-01-01T23:59:59.000Z

326

Modeling Water Management in Polymer-Electrolyte Fuel Cells  

Science Conference Proceedings (OSTI)

Fuel cells may become the energy-delivery devices of the 21st century with realization of a carbon-neutral energy economy. Although there are many types of fuel cells, polymerelectrolyte fuel cells (PEFCs) are receiving the most attention for automotive and small stationary applications. In a PEFC, hydrogen and oxygen are combined electrochemically to produce water, electricity, and waste heat. During the operation of a PEFC, many interrelated and complex phenomena occur. These processes include mass and heat transfer, electrochemical reactions, and ionic and electronic transport. Most of these processes occur in the through-plane direction in what we term the PEFC sandwich as shown in Figure 1. This sandwich comprises multiple layers including diffusion media that can be composite structures containing a macroporous gas-diffusion layer (GDL) and microporous layer (MPL), catalyst layers (CLs), flow fields or bipolar plates, and a membrane. During operation fuel is fed into the anode flow field, moves through the diffusion medium, and reacts electrochemically at the anode CL to form hydrogen ions and electrons. The oxidant, usually oxygen in air, is fed into the cathode flow field, moves through the diffusion medium, and is electrochemically reduced at the cathode CL by combination with the generated protons and electrons. The water, either liquid or vapor, produced by the reduction of oxygen at the cathode exits the PEFC through either the cathode or anode flow field. The electrons generated at the anode pass through an external circuit and may be used to perform work before they are consumed at the cathode. The performance of a PEFC is most often reported in the form of a polarization curve, as shown in Figure 2. Roughly speaking, the polarization curve can be broken down into various regions. First, it should be noted that the equilibrium potential differs from the open-circuit voltage due mainly to hydrogen crossover through the membrane (i.e., a mixed potential on the cathode) and the resulting effects of the kinetic reactions. Next, at low currents, the behavior of a PEFC is dominated by kinetic losses. These losses mainly stem from the high overpotential of the oxygen-reduction reaction (ORR). As the current is increased, ohmic losses become a factor in lowering the overall cell potential. These ohmic losses are mainly from ionic losses in the electrodes and separator. At high currents, mass-transport limitations become increasingly important. These losses are due to reactants not being able to reach the electrocatalytic sites. Key among the issues facing PEFCs today is water management. Due to their low operating temperature (transfer limitations). Figure 3 displays experimental evidence of the effects of water management on performance. In Figure 3(a), a neutron image of water content displays flooding near the outlet of the cell due to accumulation of liquid water and a decrease in the gas flowrates. The serpentine flow field is clearly visible with the water mainly underneath the ribs. Figure 3(b) shows polarization performance at 0.4 and 0.8 V and high-frequency resistance at 0.8 V as a function of cathode humidification temperature. At low current densities, as the inlet air becomes more humid, the membrane resistance decreases, and the performance increases. At higher current densities, the same effect occurs; however, the higher temperatures and more humid air also results in a lower inlet oxygen partial pressure.

Department of Chemical Engineering, University of California, Berkeley; Weber, Adam; Weber, Adam Z.; Balliet, Ryan; Gunterman, Haluna P.; Newman, John

2007-09-07T23:59:59.000Z

327

Modeling Water Management in Polymer-Electrolyte Fuel Cells  

E-Print Network (OSTI)

2007). T. I. I. Toray Carbon Fiber Paper "TGP-H" Propertya GDL is comprised of carbon fibers which have been treatedpathways from through the carbon- fiber interces, and the

Weber, Adam; Department of Chemical Engineering, University of California, Berkeley

2008-01-01T23:59:59.000Z

328

Modeling Water Management in Polymer-Electrolyte Fuel Cells  

DOE Green Energy (OSTI)

Fuel cells may become the energy-delivery devices of the 21st century with realization of a carbon-neutral energy economy. Although there are many types of fuel cells, polymerelectrolyte fuel cells (PEFCs) are receiving the most attention for automotive and small stationary applications. In a PEFC, hydrogen and oxygen are combined electrochemically to produce water, electricity, and waste heat. During the operation of a PEFC, many interrelated and complex phenomena occur. These processes include mass and heat transfer, electrochemical reactions, and ionic and electronic transport. Most of these processes occur in the through-plane direction in what we term the PEFC sandwich as shown in Figure 1. This sandwich comprises multiple layers including diffusion media that can be composite structures containing a macroporous gas-diffusion layer (GDL) and microporous layer (MPL), catalyst layers (CLs), flow fields or bipolar plates, and a membrane. During operation fuel is fed into the anode flow field, moves through the diffusion medium, and reacts electrochemically at the anode CL to form hydrogen ions and electrons. The oxidant, usually oxygen in air, is fed into the cathode flow field, moves through the diffusion medium, and is electrochemically reduced at the cathode CL by combination with the generated protons and electrons. The water, either liquid or vapor, produced by the reduction of oxygen at the cathode exits the PEFC through either the cathode or anode flow field. The electrons generated at the anode pass through an external circuit and may be used to perform work before they are consumed at the cathode. The performance of a PEFC is most often reported in the form of a polarization curve, as shown in Figure 2. Roughly speaking, the polarization curve can be broken down into various regions. First, it should be noted that the equilibrium potential differs from the open-circuit voltage due mainly to hydrogen crossover through the membrane (i.e., a mixed potential on the cathode) and the resulting effects of the kinetic reactions. Next, at low currents, the behavior of a PEFC is dominated by kinetic losses. These losses mainly stem from the high overpotential of the oxygen-reduction reaction (ORR). As the current is increased, ohmic losses become a factor in lowering the overall cell potential. These ohmic losses are mainly from ionic losses in the electrodes and separator. At high currents, mass-transport limitations become increasingly important. These losses are due to reactants not being able to reach the electrocatalytic sites. Key among the issues facing PEFCs today is water management. Due to their low operating temperature (< 100 C), water exists in both liquid and vapor phases. Furthermore, state-of-the-art membranes require the use of water to provide high conductivity and fast proton transport. Thus, there is a tradeoff between having enough water for proton conduction (ohmic losses), but not too much or else the buildup of liquid water will cause a situation in which the reactant-gas-transport pathways are flooded (mass-transfer limitations). Figure 3 displays experimental evidence of the effects of water management on performance. In Figure 3(a), a neutron image of water content displays flooding near the outlet of the cell due to accumulation of liquid water and a decrease in the gas flowrates. The serpentine flow field is clearly visible with the water mainly underneath the ribs. Figure 3(b) shows polarization performance at 0.4 and 0.8 V and high-frequency resistance at 0.8 V as a function of cathode humidification temperature. At low current densities, as the inlet air becomes more humid, the membrane resistance decreases, and the performance increases. At higher current densities, the same effect occurs; however, the higher temperatures and more humid air also results in a lower inlet oxygen partial pressure.

Department of Chemical Engineering, University of California, Berkeley; Weber, Adam; Weber, Adam Z.; Balliet, Ryan; Gunterman, Haluna P.; Newman, John

2007-09-07T23:59:59.000Z

329

Modeling Water Management in Polymer-Electrolyte Fuel Cells  

E-Print Network (OSTI)

67   3.2.3 Temperature-gradient (heat-pipe)water management ( e.g . , heat-pipe effect), examination ofsubstantially due to this heat-pipe effect. Due to the

Weber, Adam; Department of Chemical Engineering, University of California, Berkeley

2008-01-01T23:59:59.000Z

330

Virus-assembled flexible electrode-electrolyte interfaces for enhanced polymer-based battery applications  

Science Conference Proceedings (OSTI)

High-aspect-ratio cobalt-oxide-coated Tobacco mosaic virus (TMV-) assembled polytetrafluoroethylene (PTFE) nonstick surfaces were integrated with a solvent-free polymer electrolyte to create an anode-electrolyte interface for use in lithium-ion batteries. ...

Ayan Ghosh, Juchen Guo, Adam D. Brown, Elizabeth Royston, Chunsheng Wang, Peter Kofinas, James N. Culver

2012-01-01T23:59:59.000Z

331

Device for equalizing molten electrolyte content in a fuel cell stack  

DOE Patents (OSTI)

A device for equalizing the molten electrolyte content throughout the height of a fuel cell stack is disclosed. The device includes a passageway for electrolyte return with electrolyte wettable wicking material in the opposite end portions of the passageway. One end portion is disposed near the upper, negative end of the stack where electrolyte flooding occurs. The second end portion is placed near the lower, positive end of the stack where electrolyte is depleted. Heating means are provided at the upper portion of the passageway to increase electrolyte vapor pressure in the upper wicking material. The vapor is condensed in the lower passageway portion and conducted as molten electrolyte in the lower wick to the positive end face of the stack. An inlet is provided to inject a modifying gas into the passageway and thereby control the rate of electrolyte return.

Smith, James L. (Lemont, IL)

1987-01-01T23:59:59.000Z

332

Fuel cell and system for supplying electrolyte thereto utilizing cascade feed  

DOE Patents (OSTI)

An electrolyte distribution supply system for use with a fuel cell having a wicking medium for drawing electrolyte therein is formed by a set of containers of electrolyte joined to respective fuel cells or groups thereof in a stack of such cells. The electrolyte is separately stored so as to provide for electrical isolation between electrolytes of the individual cells or groups of cells of the stack. Individual storage compartments are coupled by individual tubes, the ends of the respective tubes terminating on the wicking medium in each of the respective fuel cells. The individual compartments are filled with electrolyte by allowing the compartments to overflow such as in a cascading fashion thereby maintaining the requisite depth of electrolyte in each of the storage compartments. The individual compartments can also contain packed carbon fibers to provide a three stage electrolyte distribution system.

Feigenbaum, Haim (Highland Park, NJ)

1984-01-01T23:59:59.000Z

333

Alternative flow-field and backing concepts for polymer electrolyte fuel cells  

DOE Green Energy (OSTI)

New concepts for potentially low cost flow-field and electrode backing components for polymer electrolyte fuel cells are investigated.

Wilson, M.S.; Springer, T.E.; Davey, J.R.; Gottesfeld, S.

1995-09-01T23:59:59.000Z

334

Improved electrolytes for fuel cells. Final report, June 16, 1988--June 15, 1990  

DOE Green Energy (OSTI)

Present day fuel cells based upon hydrogen and oxygen have limited performance due to the use of phosphoric acid as an electrolyte. Improved performance is desirable in electrolyte conductivity, electrolyte management, oxygen solubility, and the kinetics of the reduction of oxygen. Attention has turned to fluorosulfonic acids as additives or substitute electrolytes to improve fuel cell performance. The purpose of this project is to synthesize and electrochemically evaluate new fluorosulfonic acids as superior alternatives to phosphoric acid in fuel cells. (VC)

Gard, G.L.; Roe, D.K.

1991-06-01T23:59:59.000Z

335

Modeling of Mechano-chemical Degradation of Polymer Membranes ...  

Science Conference Proceedings (OSTI)

Abstract Scope, A transient, non-isothermal, two-dimensional (2D) model for the mechano-chemical degradation of a polymer membrane in a polymer electrolyte

336

Electrolytic hydrogen production: an analysis and review  

SciTech Connect

The thermodynamics of water electrolysis cells is presented, followed by a review of current and future technology of commercial cells. The irreversibilities involved are analyzed and the resulting equations assembled into a computer simulation model of electrolysis cell efficiency. The model is tested by comparing predictions based on the model to actual commercial cell performance, and a parametric investigation of operating conditions is performed. Finally, the simulation model is applied to a study of electrolysis cell dynamics through consideration of an ideal pulsed electrolyzer. (Author) (GRA)

Evangelista, J.; Phillips, B.; Gordon, L.

1975-12-01T23:59:59.000Z

337

Lithium/V6O13 cells using silica nanoparticle-based composite electrolyte  

E-Print Network (OSTI)

Lithium/V6O13 cells using silica nanoparticle-based composite electrolyte Yangxing Li, Peter S) both in liquid electrolyte consisting of oligomeric poly(ethyleneglycol)dimethylether'/lithium bis of suppressing lithium dendrite growth due to the rigidity and immobility of the electrolyte structure

Khan, Saad A.

338

Adsorption analysis of ammonia in an aqueous solution  

SciTech Connect

An analysis is carried out to determine the effects of the diffusional resistance on the rate of the adsorption of ammonia in an aqueous solution. A performance prediction model is developed to calculate the local rate of heat and mass transfer, including physical and thermodynamic property calculations of the mixture. An algorithm is developed for calculating the interfacial conditions. The local heat- and mass-transfer calculation is then incorporated into the performance prediction method for adsorption for a given geometry.

Arman, B.; Panchal, C.B.

1993-08-01T23:59:59.000Z

339

REMOVAL OF CHLORIDE FROM AQUEOUS SOLUTIONS  

DOE Patents (OSTI)

The removal of chlorides from aqueons solutions is described. The process involves contacting the aqueous chloride containing solution with a benzene solution about 0.005 M in phenyl mercuric acetate whereby the chloride anions are taken up by the organic phase and separating the organic phase from the aqueous solutions.

Schulz, W.W.

1959-08-01T23:59:59.000Z

340

Proton Channel Orientation in Block-Copolymer Electrolyte Membranes  

NLE Websites -- All DOE Office Websites (Extended Search)

Proton Channel Orientation in Block-Copolymer Electrolyte Membranes Print Proton Channel Orientation in Block-Copolymer Electrolyte Membranes Print Fuel cells have the potential to provide power for a wide variety of applications ranging from electronic devices to transportation vehicles. Cells operating with H2 and air as inputs and electric power and water as the only outputs are of particular interest because of their ability to produce power without degrading the environment. Polymer electrolyte membranes (PEMs), with hydrophilic, proton-conducting channels embedded in a structurally sound hydrophobic matrix, play a central role in the operation of polymer electrolyte fuel cells. PEMs are humidified by contact with air (the presence of water in PEMs is essential for proton transport). In addition, PEMs must transport protons to catalyst sites, which are typically crystalline solids such as platinum. The arrangement of the hydrophilic domains in the vicinity of both air and solid substrates is thus crucial. A University of California, Berkeley, and Berkeley Lab group has now provided the first set of data on morphology of PEMs at interfaces by a combination of x-ray scattering and microscopy.

Note: This page contains sample records for the topic "aqueous electrolyte modeling" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Proton Channel Orientation in Block-Copolymer Electrolyte Membranes  

NLE Websites -- All DOE Office Websites (Extended Search)

Proton Channel Orientation in Block-Copolymer Electrolyte Membranes Print Proton Channel Orientation in Block-Copolymer Electrolyte Membranes Print Fuel cells have the potential to provide power for a wide variety of applications ranging from electronic devices to transportation vehicles. Cells operating with H2 and air as inputs and electric power and water as the only outputs are of particular interest because of their ability to produce power without degrading the environment. Polymer electrolyte membranes (PEMs), with hydrophilic, proton-conducting channels embedded in a structurally sound hydrophobic matrix, play a central role in the operation of polymer electrolyte fuel cells. PEMs are humidified by contact with air (the presence of water in PEMs is essential for proton transport). In addition, PEMs must transport protons to catalyst sites, which are typically crystalline solids such as platinum. The arrangement of the hydrophilic domains in the vicinity of both air and solid substrates is thus crucial. A University of California, Berkeley, and Berkeley Lab group has now provided the first set of data on morphology of PEMs at interfaces by a combination of x-ray scattering and microscopy.

342

Proton Channel Orientation in Block-Copolymer Electrolyte Membranes  

NLE Websites -- All DOE Office Websites (Extended Search)

Proton Channel Orientation in Block-Copolymer Electrolyte Membranes Print Proton Channel Orientation in Block-Copolymer Electrolyte Membranes Print Fuel cells have the potential to provide power for a wide variety of applications ranging from electronic devices to transportation vehicles. Cells operating with H2 and air as inputs and electric power and water as the only outputs are of particular interest because of their ability to produce power without degrading the environment. Polymer electrolyte membranes (PEMs), with hydrophilic, proton-conducting channels embedded in a structurally sound hydrophobic matrix, play a central role in the operation of polymer electrolyte fuel cells. PEMs are humidified by contact with air (the presence of water in PEMs is essential for proton transport). In addition, PEMs must transport protons to catalyst sites, which are typically crystalline solids such as platinum. The arrangement of the hydrophilic domains in the vicinity of both air and solid substrates is thus crucial. A University of California, Berkeley, and Berkeley Lab group has now provided the first set of data on morphology of PEMs at interfaces by a combination of x-ray scattering and microscopy.

343

Proton Channel Orientation in Block-Copolymer Electrolyte Membranes  

NLE Websites -- All DOE Office Websites (Extended Search)

Proton Channel Orientation in Block-Copolymer Electrolyte Membranes Print Proton Channel Orientation in Block-Copolymer Electrolyte Membranes Print Fuel cells have the potential to provide power for a wide variety of applications ranging from electronic devices to transportation vehicles. Cells operating with H2 and air as inputs and electric power and water as the only outputs are of particular interest because of their ability to produce power without degrading the environment. Polymer electrolyte membranes (PEMs), with hydrophilic, proton-conducting channels embedded in a structurally sound hydrophobic matrix, play a central role in the operation of polymer electrolyte fuel cells. PEMs are humidified by contact with air (the presence of water in PEMs is essential for proton transport). In addition, PEMs must transport protons to catalyst sites, which are typically crystalline solids such as platinum. The arrangement of the hydrophilic domains in the vicinity of both air and solid substrates is thus crucial. A University of California, Berkeley, and Berkeley Lab group has now provided the first set of data on morphology of PEMs at interfaces by a combination of x-ray scattering and microscopy.

344

Proton Channel Orientation in Block-Copolymer Electrolyte Membranes  

NLE Websites -- All DOE Office Websites (Extended Search)

Proton Channel Orientation in Block-Copolymer Electrolyte Membranes Print Proton Channel Orientation in Block-Copolymer Electrolyte Membranes Print Fuel cells have the potential to provide power for a wide variety of applications ranging from electronic devices to transportation vehicles. Cells operating with H2 and air as inputs and electric power and water as the only outputs are of particular interest because of their ability to produce power without degrading the environment. Polymer electrolyte membranes (PEMs), with hydrophilic, proton-conducting channels embedded in a structurally sound hydrophobic matrix, play a central role in the operation of polymer electrolyte fuel cells. PEMs are humidified by contact with air (the presence of water in PEMs is essential for proton transport). In addition, PEMs must transport protons to catalyst sites, which are typically crystalline solids such as platinum. The arrangement of the hydrophilic domains in the vicinity of both air and solid substrates is thus crucial. A University of California, Berkeley, and Berkeley Lab group has now provided the first set of data on morphology of PEMs at interfaces by a combination of x-ray scattering and microscopy.

345

Proton Channel Orientation in Block-Copolymer Electrolyte Membranes  

NLE Websites -- All DOE Office Websites (Extended Search)

Proton Channel Orientation in Proton Channel Orientation in Block-Copolymer Electrolyte Membranes Proton Channel Orientation in Block-Copolymer Electrolyte Membranes Print Wednesday, 27 January 2010 00:00 Fuel cells have the potential to provide power for a wide variety of applications ranging from electronic devices to transportation vehicles. Cells operating with H2 and air as inputs and electric power and water as the only outputs are of particular interest because of their ability to produce power without degrading the environment. Polymer electrolyte membranes (PEMs), with hydrophilic, proton-conducting channels embedded in a structurally sound hydrophobic matrix, play a central role in the operation of polymer electrolyte fuel cells. PEMs are humidified by contact with air (the presence of water in PEMs is essential for proton transport). In addition, PEMs must transport protons to catalyst sites, which are typically crystalline solids such as platinum. The arrangement of the hydrophilic domains in the vicinity of both air and solid substrates is thus crucial. A University of California, Berkeley, and Berkeley Lab group has now provided the first set of data on morphology of PEMs at interfaces by a combination of x-ray scattering and microscopy.

346

Transpassive electrodissolution of depleted uranium in alkaline electrolytes  

SciTech Connect

To aid in removal of oralloy from the nuclear weapons stockpile, scientists at the Los Alamos National Laboratory Plutonium Facility are decontaminating oralloy parts by electrodissolution in neutral to alkaline electrolytes composed of sodium nitrate and sodium sulfate. To improve the process, electrodissolution experiments were performed with depleted uranium to understand the effects of various operating parameters. Sufficient precipitate was also produced to evaluate the feasibility of using ultrafiltration to separate the uranium oxide precipitates from the electrolyte before it enters the decontamination fixture. In preparation for the experiments, a potential-pH diagram for uranium was constructed from thermodynamic data for fully hydrated species. Electrodissolution in unstirred solutions showed that uranium dissolution forms two layers, an acidic bottom layer rich in uranium and an alkaline upper layer. Under stirred conditions results are consistent with the formation of a yellow precipitate of composition UO{sub 3}{center_dot}2H{sub 2}O, a six electron process. Amperometric experiments showed that current efficiency remained near 100% over a wide range of electrolytes, electrolyte concentrations, pH, and stirring conditions.

Weisbrod, K.R.; Schake, A.R.; Morgan, A.N.; Purdy, G.M.; Martinez, H.E.; Nelson, T.O.

1998-03-01T23:59:59.000Z

347

Method of making a mat-immobilized-electrolyte battery  

SciTech Connect

A method is described of assembling and preparing a mat-immobilized-electrolyte, Pb-acid storage battery for service comprising the steps of: alternatively stacking a plurality of positive and negative polarity electrodes together so as to provide a cell element having an inter-electrode gap between adjacent electrodes during the operation of the battery; positioning a separator in each said gap, said separator comprising a mat of randomly oriented, resilient glass fibers and a binder holding said mat in a stressed state at a compressed thickness which is at least about 10 percent less than said gap, said mat, in its uncompressed state, having a thickness greater than said gap, and said binder comprising a resin which is substantially insoluable in the battery's electrolyte but is sufficiently degradable therein under battery formation conditions as to free said mat from said stressed state during formation; positioning the stacked electrodes and separators in a battery container; introducing said electrolyte into said container such that it quickly flows between said electrodes substantially unencumbered by said compressed mat; allowing said battery to stand for a time sufficient to pickle said electrodes; and thereafter electrolytically forming said battery so as to initially charge said battery and so degrade said binder that said mat expands into tight engagement with the electrodes adjacent thereto.

Willmann, N.L.; Eisenhut, N.R.; Limbert, J.L.

1993-08-31T23:59:59.000Z

348

On-site production of electrolytic hydrogen for generator cooling  

SciTech Connect

Hydrogen produced by water electrolysis could be cost effective over the merchant hydrogen used for generator cooling. Advanced water electrolyzers are being developed specifically for this utility application. These designs are based on solid-polymer-electrolyte and alkaline water electrolysis technologies. This paper describes the status of electrolyzer development and demonstration projects.

Mehta, B.

1982-08-01T23:59:59.000Z

349

Low hydrostatic head electrolyte addition to fuel cell stacks  

DOE Patents (OSTI)

A fuel cell and system for supply electrolyte, as well as fuel and an oxidant to a fuel cell stack having at least two fuel cells, each of the cells having a pair of spaced electrodes and a matrix sandwiched therebetween, fuel and oxidant paths associated with a bipolar plate separating each pair of adjacent fuel cells and an electrolyte fill path for adding electrolyte to the cells and wetting said matrices. Electrolyte is flowed through the fuel cell stack in a back and forth fashion in a path in each cell substantially parallel to one face of opposite faces of the bipolar plate exposed to one of the electrodes and the matrices to produce an overall head uniformly between cells due to frictional pressure drop in the path for each cell free of a large hydrostatic head to thereby avoid flooding of the electrodes. The bipolar plate is provided with channels forming paths for the flow of the fuel and oxidant on opposite faces thereof, and the fuel and the oxidant are flowed along a first side of the bipolar plate and a second side of the bipolar plate through channels formed into the opposite faces of the bipolar plate, the fuel flowing through channels formed into one of the opposite faces and the oxidant flowing through channels formed into the other of the opposite faces.

Kothmann, Richard E. (Churchill Boro, PA)

1983-01-01T23:59:59.000Z

350

Electrolytic production of high purity aluminum using inert anodes  

DOE Patents (OSTI)

A method of producing commercial purity aluminum in an electrolytic reduction cell comprising inert anodes is disclosed. The method produces aluminum having acceptable levels of Fe, Cu and Ni impurities. The inert anodes used in the process preferably comprise a cermet material comprising ceramic oxide phase portions and metal phase portions.

Ray, Siba P. (Murrysville, PA); Liu, Xinghua (Monroeville, PA); Weirauch, Jr., Douglas A. (Murrysville, PA)

2001-01-01T23:59:59.000Z

351

Electrolytic production of high purity aluminum using ceramic inert anodes  

DOE Patents (OSTI)

A method of producing commercial purity aluminum in an electrolytic reduction cell comprising ceramic inert anodes is disclosed. The method produces aluminum having acceptable levels of Fe, Cu and Ni impurities. The ceramic inert anodes used in the process may comprise oxides containing Fe and Ni, as well as other oxides, metals and/or dopants.

Ray, Siba P. (Murrysville, PA); Liu, Xinghua (Monroeville, PA); Weirauch, Douglas A. (Murrysville, PA); DiMilia, Robert A. (Baton Rouge, LA); Dynys, Joseph M. (New Kensington, PA); Phelps, Frankie E. (Apollo, PA); LaCamera, Alfred F. (Trafford, PA)

2002-01-01T23:59:59.000Z

352

Integrated photoelectrochemical cell and system having a liquid electrolyte  

DOE Patents (OSTI)

An integrated photoelectrochemical (PEC) cell generates hydrogen and oxygen from water while being illuminated with radiation. The PEC cell employs a liquid electrolyte, a multi-junction photovoltaic electrode, and a thin ion-exchange membrane. A PEC system and a method of making such PEC cell and PEC system are also disclosed.

Deng, Xunming (Sylvania, OH); Xu, Liwei (Sylvania, OH)

2010-07-06T23:59:59.000Z

353

New electrolytes for direct methane fuel cells. Final report, January 10,1977-January 9, 1979. [Methanesulfonic acids  

DOE Green Energy (OSTI)

The program is aimed at developing a fuel cell electrolyte for the direct oxidation of CH/sub 4/ and/or impure H/sub 2/ fuels. Of interest are di- and tribasic methanesulfonic acids CX/sub 2/(SO/sub 3/H)/sub 2/ and CX(SO/sub 3/H)/sub 3/ where X is H, F, or C1. Synthetic routes to CH/sub 2/(SO/sub 3/H)/sub 2/, CH(SO/sub 3/H)/sub 3/, CCl/sub 2/(SO/sub 3/H)/sub 2/, and CCl(SO/sub 3/H)/sub 3/ have been identified and optimized. The diphenyl ester of CF/sub 2/(SO/sub 3/H)/sub 2/ has been prepared for the first time and various approaches to CF(SO/sub 3/H)/sub 3/ have been investigated. In parallel with the synthetic program, apparatus was designed and fabricated for the testing of the electrolytes under fuel cell conditions. A new PTFE test cell was developed for testing small amounts of electrolyte. Electrodes with low Pt loading were developed for use in electrolyte evaluation. Optimum performance with H/sub 3/PO/sub 4/ was achieved using 1 mg Pt/cm/sup 2/ and 1 mg TFE 30/cm/sup 2/ deposited on TFE tape, supported on a Au plated Ta screen, and sintered. Preliminary half cell tests using CH/sub 2/(SO/sub 3/H)/sub 2/ and CH(SO/sub 3/H)/sub 3/ indicated that these acids are insufficiently stable for use as fuel cell electrolytes. However, tests using CCl/sub 2/(SO/sub 3/H/sub 2/) and CCl(SO/sub 3/H)/sub 3/ were encouraging, yielding H/sub 2/ oxidation rates equal to or better than those using H/sub 3/PO/sub 4/. Stability tests were conducted by heating a sample of each acid at 130/sup 0/ for 30 days under atmospheres of N/sub 2/, O/sub 2/, and H/sub 2/. At the end of the test, each sample was analyzed for decomposition. In no case did IR analysis indicate significant decomposition and, in the case of the chloroacids, only a trace amount of free Cl/sup -/ was observed. Conductivity measurements showed the aqueous acids to be of the same conductivty as aqueous H/sub 3/PO/sub 4/. The dihydrate of CH/sub 2/(SO/sub 3/H)/sub 2/ was found to be more conductive than CF/sub 3/SO/sub 3/H.H/sub 2/O but less conductive than 100% H/sub 3/PO/sub 4/.

Brummer, S.B.; Foos, J.; McHardy, J.; McVeigh, J.; Toland, D.; Turner, M.

1979-05-01T23:59:59.000Z

354

Lithium Ion Transport Mechanism in Ternary Polymer Electrolyte-Ionic Liquid Mixtures - A Molecular Dynamics Simulation Study  

E-Print Network (OSTI)

The lithium transport mechanism in ternary polymer electrolytes, consisting of PEO/LiTFSI and various fractions of the ionic liquid N-methyl-N-propylpyrrolidinium bis(trifluoromethane)sulfonimide, are investigated by means of MD simulations. This is motivated by recent experimental findings [Passerini et al., Electrochim. Acta 2012, 86, 330-338], which demonstrated that these materials display an enhanced lithium mobility relative to their binary counterpart PEO/LiTFSI. In order to grasp the underlying microscopic scenario giving rise to these observations, we employ an analytical, Rouse-based cation transport model [Maitra at al., PRL 2007, 98, 227802], which has originally been devised for conventional polymer electrolytes. This model describes the cation transport via three different mechanisms, each characterized by an individual time scale. It turns out that also in the ternary electrolytes essentially all lithium ions are coordinated by PEO chains, thus ruling out a transport mechanism enhanced by the presence of ionic-liquid molecules. Rather, the plasticizing effect of the ionic liquid contributes to the increased lithium mobility by enhancing the dynamics of the PEO chains and consequently also the motion of the attached ions. Additional focus is laid on the prediction of lithium diffusion coefficients from the simulation data for various chain lengths and the comparison with experimental data, thus demonstrating the broad applicability of our approach.

Diddo Diddens; Andreas Heuer

2012-11-14T23:59:59.000Z

355

Method for processing aqueous wastes  

DOE Patents (OSTI)

This invention is comprised of a method for treating waste water such as that from an industrial processing facility comprising the separation of the waste water into a dilute waste stream and a concentrated waste stream. The concentrated waste stream is treated chemically to enhance precipitation and then allowed to separate into a sludge and a supernate. The supernate is skimmed or filtered from the sludge and blended with the dilute waste stream to form a second dilute waste stream. The sludge remaining is mixed with cementitious material, rinsed to dissolve soluble components, then pressed to remove excess water and dissolved solids before being allowed to cure. The dilute waste stream is also chemically treated to decompose carbonate complexes and metal ions and then mixed with cationic polymer to cause the precipitated solids to flocculate. Filtration of the flocculant removes sufficient solids to allow the waste water to be discharged to the surface of a stream. The filtered material is added to the sludge of the concentrated waste stream. The method is also applicable to the treatment and removal of soluble uranium from aqueous streams, such that the treated stream may be used as a potable water supply.

Pickett, J.B.; Martin, H.L.; Langton, C.A.; Harley, W.W.

1992-12-31T23:59:59.000Z

356

Method for processing aqueous wastes  

DOE Patents (OSTI)

A method is presented for treating waste water such as that from an industrial processing facility comprising the separation of the waste water into a dilute waste stream and a concentrated waste stream. The concentrated waste stream is treated chemically to enhance precipitation and then allowed to separate into a sludge and a supernate. The supernate is skimmed or filtered from the sludge and blended with the dilute waste stream to form a second dilute waste stream. The sludge remaining is mixed with cementitious material, rinsed to dissolve soluble components, then pressed to remove excess water and dissolved solids before being allowed to cure. The dilute waste stream is also chemically treated to decompose carbonate complexes and metal ions and then mixed with cationic polymer to cause the precipitated solids to flocculate. Filtration of the flocculant removes sufficient solids to allow the waste water to be discharged to the surface of a stream. The filtered material is added to the sludge of the concentrated waste stream. The method is also applicable to the treatment and removal of soluble uranium from aqueous streams, such that the treated stream may be used as a potable water supply. 4 figures.

Pickett, J.B.; Martin, H.L.; Langton, C.A.; Harley, W.W.

1993-12-28T23:59:59.000Z

357

Method for processing aqueous wastes  

DOE Patents (OSTI)

A method for treating waste water such as that from an industrial processing facility comprising the separation of the waste water into a dilute waste stream and a concentrated waste stream. The concentrated waste stream is treated chemically to enhance precipitation and then allowed to separate into a sludge and a supernate. The supernate is skimmed or filtered from the sludge and blended with the dilute waste stream to form a second dilute waste stream. The sludge remaining is mixed with cementitious material, rinsed to dissolve soluble components, then pressed to remove excess water and dissolved solids before being allowed to cure. The dilute waste stream is also chemically treated to decompose carbonate complexes and metal ions and then mixed with cationic polymer to cause the precipitated solids to flocculate. Filtration of the flocculant removes sufficient solids to allow the waste water to be discharged to the surface of a stream. The filtered material is added to the sludge of the concentrated waste stream. The method is also applicable to the treatment and removal of soluble uranium from aqueous streams, such that the treated stream may be used as a potable water supply.

Pickett, John B. (3922 Wood Valley Dr., Aiken, SC 29803); Martin, Hollis L. (Rt. 1, Box 188KB, McCormick, SC 29835); Langton, Christine A. (455 Sumter St. SE., Aiken, SC 29801); Harley, Willie W. (110 Fairchild St., Batesburg, SC 29006)

1993-01-01T23:59:59.000Z

358

Control of electrolyte fill to fuel cell stack  

DOE Patents (OSTI)

A fuel cell stack which can be operated with cells in a horizontal position so that the fuel cell stack does not have to be taken out of operation when adding an electrolyte such as an acid. Acid is supplied to each matrix in a stack of fuel cells at a uniform, low pressure so that the matrix can either be filled initially or replenished with acid lost in operation of the cell, without exceeding the bubble pressure of the matrix or the flooding pressure of the electrodes on either side of the matrix. Acid control to each cell is achieved by restricting and offsetting the opening of electrolyte fill holes in the matrix relative to openings in the plates which sandwich the matrix and electrodes therebetween.

Pollack, William (Scott Township, Allegheny County, PA)

1982-01-01T23:59:59.000Z

359

ELECTROLYTIC DISINTEGRATION OF ZIRCALOY-2 IN NITRIC ACID SOLUTIONS  

SciTech Connect

Zircaloy-2 is anodically converted to scaly ZrO/sub 2/ at 60 deg C in 8 M HNO/sub 3/. About 0.5 mole of acid is consumed per faraday, and after saturation of the electrolyte with nitrogen oxides about 0.3 mole of gas is evolved per faraday. The nitric acid is reduced to hydrogen, NO, and N0/sub 2/, with hydrogen predominating if the cathode is Zircaloy and NO if the cathode is platinum. Corrosion specimens of HRT metals were exposed to the electrolysis conditions. From determinations of the decomposition potential of nitric acid it appears that a metal container for the electrolytic process can be protected from stray-current corrosion by holdlng it at a potential --0.5 volt positive to a platinum cathode operating at a current density of 5 to 10 ma/cm/sup 2/. Practical laboratory experiments tended to confirm this conclusion. (auth)

Clark, W.E.; Peterson, S.

1959-11-27T23:59:59.000Z

360

Stationary power applications for polymer electrolyte fuel cells  

DOE Green Energy (OSTI)

The benefits provided by Polymer Electrolyte Fuel Cells (PEFC) for power generation (e.g. low operating temperatures, and non-corrosive and stable electrolyte), as well as advances in recent years in lowering their cost and improving anode poisoning tolerance, are stimulating interest in the system for stationary power applications. A significant market potentially exists for PEFCs in certain stationary applications where PEFC technology is a more attractive alternative to other fuel cell technologies. A difficulty with the PEFC is its operation on reformed fuels containing CO, which poisons the anode catalyst. This difficulty can be alleviated in several ways. One possible approach is described whereby the product reformate is purified using a relatively low cost, high-throughput hydrogen permselective separator. Preliminary experiments demonstrate the utility of the concept.

Wilson, M.S.; Zawodzinski, C.; Gottesfeld, S. [Los Alamos National Lab., NM (United States); Landgrebe, A.R. [Dept. of Energy, Washington, DC (United States)

1996-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "aqueous electrolyte modeling" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Solid polymer battery electrolyte and reactive metal-water battery  

SciTech Connect

In one implementation, a reactive metal-water battery includes an anode comprising a metal in atomic or alloy form selected from the group consisting of periodic table Group 1A metals, periodic table Group 2A metals and mixtures thereof. The battery includes a cathode comprising water. Such also includes a solid polymer electrolyte comprising a polyphosphazene comprising ligands bonded with a phosphazene polymer backbone. The ligands comprise an aromatic ring containing hydrophobic portion and a metal ion carrier portion. The metal ion carrier portion is bonded at one location with the polymer backbone and at another location with the aromatic ring containing hydrophobic portion. The invention also contemplates such solid polymer electrolytes use in reactive metal/water batteries, and in any other battery.

Harrup, Mason K. (Idaho Falls, ID); Peterson, Eric S. (Idaho Falls, ID); Stewart, Frederick F. (Idaho Falls, ID)

2000-01-01T23:59:59.000Z

362

Improved Electrodes and Electrolytes for Dye-Based Solar Cells  

SciTech Connect

The most important factor in limiting the stability of dye-sensitized solar cells is the use of volatile liquid solvents in the electrolytes, which causes leakage during extended operation especially at elevated temperatures. This, together with the necessary complex sealing of the cells, seriously hampers the industrial-scale manufacturing and commercialization feasibilities of DSSCs. The objective of this program was to bring about a significant improvement in the performance and longevity of dye-based solar cells leading to commercialization. This had been studied in two ways first through development of low volatility solid, gel or liquid electrolytes, second through design and fabrication of TiO2 sculptured thin film electrodes.

Harry R. Allcock; Thomas E. Mallouk; Mark W. Horn

2011-10-26T23:59:59.000Z

363

Highly conductive electrolyte composites and method of fabrication thereof  

DOE Patents (OSTI)

An electrolyte composite is manufactured by pressurizing a mixture of ionically conductive glass and an ionically conductive compound at between 12,000 and 24,000 pounds per square inch to produce a pellet. The resulting pellet is then sintered at relatively lower temperatures (800{degrees}C--1200{degrees}C), for example 1000{degrees}C, than are typically required (1400{degrees}C) when fabricating single constituent ceramic electrolytes. The resultant composite is 100 percent conductive at 250{degrees}C with conductivity values of 2.5 to 4 {times} 10{sup {minus}2} (ohm-cm){sup {minus}1}. The matrix exhibits chemical stability against sodium for 100 hours at 250 to 300{degrees}C.

Hash, M.C.; Bloom, I.D.

1990-07-17T23:59:59.000Z

364

Process for reducing aqueous nitrate to ammonia  

DOE Patents (OSTI)

Powdered aluminum is added to a nitrate-containing alkaline, aqueous solution to reduce the nitrate and/or nitrite to ammonia and co-produce a sinterable ceramic product.

Mattus, Alfred J. (Oak Ridge, TN)

1993-01-01T23:59:59.000Z

365

Radiation Chemistry of MTBE in Aqueous Solution  

NLE Websites -- All DOE Office Websites (Extended Search)

Methyl-tert-Butyl Ether (MTBE) in Aqueous Solution Stephen P. Mezyk, Jace Jones, William J. Cooper, Thomas Tobien, Michael G. Nickelsen, J. Wesley Adams, Kevin E. O'Shea, David M....

366

Process for reducing aqueous nitrate to ammonia  

DOE Patents (OSTI)

Powdered aluminum is added to a nitrate-containing alkaline, aqueous solution to reduce the nitrate and/or nitrite to ammonia and co-produce a sinterable ceramic product. 3 figures.

Mattus, A.J.

1993-11-30T23:59:59.000Z

367

Summary of aqueous mobile battery development  

SciTech Connect

Progress at ANL in developing improved aqueous battery technology for use in electric vehicles is briefly described. Research directed at improving the lead-acid, nickel/iron, and nickel/zinc technologies is emphasized. (WHK)

Christianson, C.C.; Yao, N.P.; Rajan, J.; Miller, J.; Lee, J.; Choi, K.

1982-01-01T23:59:59.000Z

368

Electrolytic recovery of mercury enriched in isotopic abundance  

DOE Patents (OSTI)

The present invention is directed to a method of electrolytically extracting liquid mercury from HgO or Hg.sub.2 Cl.sub.2. Additionally there are disclosed two related techniques associated with the present invention, namely (1) a technique for selectively removing product from different regions of a long photochemical reactor (photoreactor) and (2) a method of accurately measuring the total quantity of mercury formed as either HgO or Hg.sub.2 Cl.sub.2.

Grossman, Mark W. (Belmont, MA)

1991-01-01T23:59:59.000Z

369

Solid lithium ion conducting electrolytes and methods of preparation  

SciTech Connect

A composition comprised of nanoparticles of lithium ion conducting solid oxide material, wherein the solid oxide material is comprised of lithium ions, and at least one type of metal ion selected from pentavalent metal ions and trivalent lanthanide metal ions. Solution methods useful for synthesizing these solid oxide materials, as well as precursor solutions and components thereof, are also described. The solid oxide materials are incorporated as electrolytes into lithium ion batteries.

Narula, Chaitanya K; Daniel, Claus

2013-05-28T23:59:59.000Z

370

A van der Waals free energy in electrolytes revisited  

E-Print Network (OSTI)

A system of three electrolytes separated by two parallel planes is considered. Each region is described by a dielectric constant and a Coulomb fluid in the Debye-H\\"uckel regime. In their book Dispersion Forces, Mahanty and Ninham have given the van der Waals free energy of this system. We rederive this free energy by a different method, using linear response theory and the electrostatic Maxwell stress tensor for obtaining the dispersion force.

B. Jancovici

2005-09-15T23:59:59.000Z

371

Protective interlayer for high temperature solid electrolyte electrochemical cells  

DOE Patents (OSTI)

The invention is comprised of an electrically conducting doped or admixed cerium oxide composition with niobium oxide and/or tantalum oxide for electrochemical devices, characterized by the general formula: Nb{sub x}Ta{sub y}Ce{sub 1{minus}x{minus}y}O{sub 2} where x is about 0.0 to 0.05, y is about 0.0 to 0.05, and x+y is about 0.02 to 0.05, and where x is preferably about 0.02 to 0.05 and y is 0, and a method of making the same is also described. This novel composition is particularly applicable in forming a protective interlayer of a high temperature, solid electrolyte electrochemical cell, characterized by a first electrode; an electrically conductive interlayer of niobium and/or tantalum doped cerium oxide deposited over at least a first portion of the first electrode; an interconnect deposited over the interlayer; a solid electrolyte deposited over a second portion of the first electrode, the first portion being discontinuous from the second portion; and, a second electrode deposited over the solid electrolyte. The interlayer is characterized as being porous and selected from the group consisting of niobium doped cerium oxide, tantalum doped cerium oxide, and niobium and tantalum doped cerium oxide or admixtures of the same. The first electrode, an air electrode, is a porous layer of doped lanthanum manganite, the solid electrolyte layer is a dense yttria stabilized zirconium oxide, the interconnect layer is a dense, doped lanthanum chromite, and the second electrode, a fuel electrode, is a porous layer of nickel-zirconium oxide cermet. The electrochemical cell can take on a plurality of shapes such as annular, planar, etc. and can be connected to a plurality of electrochemical cells in series and/or in parallel to generate electrical energy. 5 figs.

Singh, P.; Vasilow, T.R.; Richards, V.L.

1996-05-14T23:59:59.000Z

372

Protective interlayer for high temperature solid electrolyte electrochemical cells  

DOE Patents (OSTI)

The invention comprises of an electrically conducting doped or admixed cerium oxide composition with niobium oxide and/or tantalum oxide for electrochemical devices, characterized by the general formula: Nb.sub.x Ta.sub.y Ce.sub.1-x-y O.sub.2 where x is about 0.0 to 0.05, y is about 0.0 to 0.05, and x+y is about 0.02 to 0.05, and where x is preferably about 0.02 to 0.05 and y is 0, and a method of making the same. This novel composition is particularly applicable in forming a protective interlayer of a high temperature, solid electrolyte electrochemical cell (10), characterized by a first electrode (12); an electrically conductive interlayer (14) of niobium and/or tantalum doped cerium oxide deposited over at least a first portion (R) of the first electrode; an interconnect (16) deposited over the interlayer; a solid electrolyte (18) deposited over a second portion of the first electrode, the first portion being discontinuous from the second portion; and, a second electrode (20) deposited over the solid electrolyte. The interlayer (14) is characterized as being porous and selected from the group consisting of niobium doped cerium oxide, tantalum doped cerium oxide, and niobium and tantalum doped cerium oxide or admixtures of the same. The first electrode (12), an air electrode, is a porous layer of doped lanthanum manganite, the solid electrolyte layer (18) is a dense yttria stabilized zirconium oxide, the interconnect layer (16) is a dense, doped lanthanum chromite, and the second electrode (20), a fuel electrode, is a porous layer of nickel-zirconium oxide cermet. The electrochemical cell (10) can take on a plurality of shapes such as annular, planar, etc. and can be connected to a plurality of electrochemical cells in series and/or in parallel to generate electrical energy.

Singh, Prabhakar (Export, PA); Vasilow, Theodore R. (Manor, PA); Richards, Von L. (Angola, IN)

1996-01-01T23:59:59.000Z

373

AQUEOUS HOMOGENEOUS REACTORTECHNICAL PANEL REPORT  

Science Conference Proceedings (OSTI)

Considerable interest has been expressed for developing a stable U.S. production capacity for medical isotopes and particularly for molybdenum- 99 (99Mo). This is motivated by recent re-ductions in production and supply worldwide. Consistent with U.S. nonproliferation objectives, any new production capability should not use highly enriched uranium fuel or targets. Conse-quently, Aqueous Homogeneous Reactors (AHRs) are under consideration for potential 99Mo production using low-enriched uranium. Although the Nuclear Regulatory Commission (NRC) has guidance to facilitate the licensing process for non-power reactors, that guidance is focused on reactors with fixed, solid fuel and hence, not applicable to an AHR. A panel was convened to study the technical issues associated with normal operation and potential transients and accidents of an AHR that might be designed for isotope production. The panel has produced the requisite AHR licensing guidance for three chapters that exist now for non-power reactor licensing: Reac-tor Description, Reactor Coolant Systems, and Accident Analysis. The guidance is in two parts for each chapter: 1) standard format and content a licensee would use and 2) the standard review plan the NRC staff would use. This guidance takes into account the unique features of an AHR such as the fuel being in solution; the fission product barriers being the vessel and attached systems; the production and release of radiolytic and fission product gases and their impact on operations and their control by a gas management system; and the movement of fuel into and out of the reactor vessel.

Diamond, D.J.; Bajorek, S.; Bakel, A.; Flanagan, G.; Mubayi, V.; Skarda, R.; Staudenmeier, J.; Taiwo, T.; Tonoike, K.; Tripp, C.; Wei, T.; Yarsky, P.

2010-12-03T23:59:59.000Z

374

aqueous and electrochemical processing ii  

Science Conference Proceedings (OSTI)

A Dynamic LCA Model For Assessing The Impact Of Lead Free Solder [pp. .... For Recycling Of Spent Nickel-Metal Hydride Secondary Battery (Invited) [pp.

375

Study of anion adsorption at the gold--aqueous solution interface by atomic force microscopy  

SciTech Connect

The forces between a gold coated colloidal silica sphere and a pure gold plate have been measured in aqueous solution as a function of electrolyte concentration using an atomic force microscope (AFM). Forces in the presence of gold(III) chloride (HAuCl[sub 4]), sodium chloride, and trisodium citrate were recorded as a function of concentration. Each of these anion species is present during the formation of colloidal gold by the reduction of gold(III) chloride with trisodium citrate. In pure water the force between the gold surfaces was exclusively attractive. In sodium chloride or trisodium citrate solution a repulsive interaction was observed which is attributed to the adsorption of these anions at the gold/water interface. The observed interaction force in gold(III) chloride solution was always attractive, the surface potential never exceeding 20 mV. Data taken in aqueous solutions of citrate and chloride ions together suggested that the citrate ions were preferentially adsorbed to the surface of the gold. Addition of gold(III) chloride to the AFM liquid cell after the pre-adsorption of citrate anions caused the force of interaction to change from a repulsvie force to an attractive one initially as the gold(III) chloride was reduced to gold by the citrate anions. 33 refs., 11 figs.

Biggs, S.; Mulvaney, P.; Grieser, F. (Univ. of Melbourne (Australia)); Zukoski, C.F. (Univ. of Illinois, Urbana, IL (United States))

1994-10-05T23:59:59.000Z

376

CHARACTERIZATION OF LOW-FLAMMABILITY ELECTROLYTES FOR LITHIUM-ION BATTERIES  

DOE Green Energy (OSTI)

In an effort to develop low-flammability electrolytes for a new generation of Li-ion batteries, we have evaluated physical and electrochemical properties of electrolytes with two proprietary phosphazene additives. We have studied performance quantities including conductivity, viscosity, flash point, and electrochemical window of electrolytes as well as formation of solid electrolyte interphase (SEI) films. In the course of study, the necessity for a simple method of SEI characterization was realized. Therefore, a new method and new criteria were developed and validated on 10 variations of electrolyte/electrode substrates. Based on the summation of determined physical and electrochemical properties of phosphazene-based electrolytes, one structure of phosphazene compound was found better than the other. This capability helps to direct our further synthetic work in phosphazene chemistry.

Sergiy V. Sazhin; Mason K. Harrup; Kevin L. Gering

2011-04-01T23:59:59.000Z

377

Electro-osmotic drag coefficient of water and methanol in polymer electrolytes at elevated temperatures  

Science Conference Proceedings (OSTI)

The electro-osmotic drag coefficient of water in two polymer electrolytes was experimentally determined as a function of water activity and current density for temperatures up to 200 C. The results show that the electro-osmotic drag coefficient varies from 0.2 to 0.6 in Nafion{reg_sign}/H{sub 3}PO{sub 4} membrane electrolyte, but is essentially zero in phosphoric acid-doped PBI (polybenzimidazole) membrane electrolyte over the range of water activity considered. The near-zero electro-osmotic drag coefficient found in PBI indicates that this electrolyte should lessen the problems associated with water redistribution in proton exchange membrane fuel cells.

Weng, D.; Wainright, J.S.; Landau, U.; Savinell, R.F. [Case Western Reserve Univ., Cleveland, OH (United States)

1996-04-01T23:59:59.000Z

378

High-Rate Oxygen Reduction in Mixed Nonaqueous Electrolyte Containing Acetonitrile  

SciTech Connect

A mixed nonaqueous electrolyte that contains acetonitrile and propylene carbonate (PC) was found to be suitable for a LiO2 battery with a metallic Li anode. Both the concentration and diffusion coefficient for the dissolved O2 are significantly higher in the mixed electrolyte than those in the pure PC electrolyte. A powder microelectrode was used to investigate the O2 solubility and diffusion coefficient. A 10 mA?cm-2 discharge rate on a gas-diffusion electrode is demonstrated by using the mixed electrolyte in a LiO2 cell.

Zheng D.; Yang X.; Qu D.

2011-12-02T23:59:59.000Z

379

Investigation of Electric Conductivity on Electrolyte-free Fuel Cells by ...  

Science Conference Proceedings (OSTI)

Abstract Scope, Single-component electrolyte-free fuel cells possess a similar function to the traditional fuel ... Composite Membranes for Hydrogen Production.

380

SEPARATION OF RUTHENIUM FROM AQUEOUS SOLUTIONS  

DOE Patents (OSTI)

>The separation of ruthenium from aqueous solutions containing uranium plutonium, ruthenium, and fission products is described. The separation is accomplished by providing a nitric acid solution of plutonium, uranium, ruthenium, and fission products, oxidizing plutonium to the hexavalent state with sodium dichromate, contacting the solution with a water-immiscible organic solvent, such as hexone, to extract plutonyl, uranyl, ruthenium, and fission products, reducing with sodium ferrite the plutonyl in the solvent phase to trivalent plutonium, reextracting from the solvent phase the trivalent plutonium, ruthenium, and some fission products with an aqueous solution containing a salting out agent, introducing ozone into the aqueous acid solution to oxidize plutonium to the hexavalent state and ruthenium to ruthenium tetraoxide, and volatizing off the ruthenium tetraoxide.

Callis, C.F.; Moore, R.L.

1959-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "aqueous electrolyte modeling" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Electrolytic production of metals using a resistant anode  

DOE Patents (OSTI)

An electrolytic process is described comprising evolving oxygen on an anode in a molten salt, the anode comprising an alloy comprising a first metal and a second metal, both metals forming oxides, the oxide of the first metal being more resistant than the second metal to attack by the molten salt, the oxide of the second metal being more resistant than the first metal to the diffusion of oxygen. The electrode may also be formed of CuAlO[sub 2] and/or Cu[sub 2]O. 2 figs.

Tarcy, G.P.; Gavasto, T.M.; Ray, S.P.

1986-11-04T23:59:59.000Z

382

Summary of Electrolytic Hydrogen Production: Milestone Completion Report  

SciTech Connect

This report provides an overview of the current state of electrolytic hydrogen production technologies and an economic analysis of the processes and systems available as of December 2003. The operating specifications of commercially available electrolyzers from five manufacturers, i.e., Stuart, Teledyne, Proton, Norsk Hydro, and Avalence, are summarized. Detailed economic analyses of three systems for which cost and economic data were available were completed. The contributions of the cost of electricity, system efficiency, and capital costs to the total cost of electrolysis are discussed.

Ivy, J.

2004-09-01T23:59:59.000Z

383

Summary of Electrolytic Hydrogen Production: Milestone Completion Report  

SciTech Connect

This report provides an overview of the current state of electrolytic hydrogen production technologies and an economic analysis of the processes and systems available as of December 2003. The operating specifications of commercially available electrolyzers from five manufacturers, i.e., Stuart, Teledyne, Proton, Norsk Hydro, and Avalence, are summarized. Detailed economic analyses of three systems for which cost and economic data were available were completed. The contributions of the cost of electricity, system efficiency, and capital costs to the total cost of electrolysis are discussed.

Ivy, J.

2004-04-01T23:59:59.000Z

384

METHOD AND MEANS FOR ELECTROLYTIC PURIFICATION OF PLUTONIUM  

DOE Patents (OSTI)

The technique of electrodepositing pure plutonium from a fused salt electrolyte of PuCl/sub 3/ and aixati metal halides is described. When an iron cathode is used, the plutonium deposit alloys therewith in the liquid state at the 400 to 600 deg C operating temperature, such liquid being allowed to drip through holes in the cathode and collect in a massive state in a tantallum cup. The process is adaptable to continuous processing by the use of depleted plutonium fuel as the anode: good to excellent separation from fission products is obtained with a Pu--Fe "fission" anode containing representative fractions of Ce, Ru, Zr, La, Mo, and Nb.

Bjorklund, C.W.; Benz, R.; Maraman, W.J.; Leary, J.A.; Walsh, K.A.

1960-02-01T23:59:59.000Z

385

Molten salt bath circulation design for an electrolytic cell  

DOE Patents (OSTI)

An electrolytic cell for reduction of a metal oxide to a metal and oxygen has an inert anode and an upwardly angled roof covering the inert mode. The angled roof diverts oxygen bubbles into an upcomer channel, thereby agitating a molten salt bath in the upcomer channel and improving dissolution of a metal oxide in the molten salt bath. The molten salt bath has a lower velocity adjacent the inert anode in order to minimize corrosion by substances in the bath. A particularly preferred cell produces aluminum by electrolysis of alumina in a molten salt bath containing aluminum fluoride and sodium fluoride.

Dawless, Robert K. (Monroeville, PA); LaCamera, Alfred F. (Trafford, PA); Troup, R. Lee (Murrysville, PA); Ray, Siba P. (Murrysville, PA); Hosler, Robert B. (Sarver, PA)

1999-01-01T23:59:59.000Z

386

Molten salt bath circulation design for an electrolytic cell  

DOE Patents (OSTI)

An electrolytic cell for reduction of a metal oxide to a metal and oxygen has an inert anode and an upwardly angled roof covering the inert mode. The angled roof diverts oxygen bubbles into an upcomer channel, thereby agitating a molten salt bath in the upcomer channel and improving dissolution of a metal oxide in the molten salt bath. The molten salt bath has a lower velocity adjacent the inert anode in order to minimize corrosion by substances in the bath. A particularly preferred cell produces aluminum by electrolysis of alumina in a molten salt bath containing aluminum fluoride and sodium fluoride. 4 figs.

Dawless, R.K.; LaCamera, A.F.; Troup, R.L.; Ray, S.P.; Hosler, R.B.

1999-08-17T23:59:59.000Z

387

Electrolytic production of metals using a resistant anode  

DOE Patents (OSTI)

An electrolytic process comprising evolving oxygen on an anode in a molten salt, the anode comprising an alloy comprising a first metal and a second metal, both metals forming oxides, the oxide of the first metal being more resistant than the second metal to attack by the molten salt, the oxide of the second metal being more resistant than the first metal to the diffusion of oxygen. The electrode may also be formed of CuAlO.sub.2 and/or Cu.sub.2 O.

Tarcy, Gary P. (Plum Borough, PA); Gavasto, Thomas M. (New Kensington, PA); Ray, Siba P. (Plum Borough, PA)

1986-01-01T23:59:59.000Z

388

THE TREATMENT OF LOW ACTIVITY AQUEOUS WASTES  

SciTech Connect

The equipment and treatment methods for processing low-activity aqueous wastes at the Latina nuclear power station are discussed. The effluent treatment plant serves two purposes: purification of cooling pond water and decontamination of aqueous wastes from such outlets as regenerant solutions, active laundry and change houses, decontamination center, coffin washing, and charge machine washing. The treatment process consists of chemical precipitation followed by filtration of the sludges thus produced. The process is then followed by ion exchange on a natural inorganic material such as vermiculite and evaporation. This process produces a decontamination factor of l0/sup 3/ to 10/ sup 4/. (N.W.R.)

Cartwright, A.C.

1962-01-01T23:59:59.000Z

389

Biomimetic oxidation studies. 11: Alkane functionalization in aqueous solution utilizing in situ formed [Fe{sub 2}O({eta}{sup 1}-H{sub 2}O)({eta}{sup 1}-OAc)(TPA){sub 2}]{sup 3+}, as an MMO model precatalyst, embedded in surface-derivatized silica and contained in micelles  

Science Conference Proceedings (OSTI)

The biomimetic, methane monooxygenase enzyme (MMO) precatalyst, [Fe{sub 2}O({eta}{sup 1}-H{sub 2}O)({eta}{sup 1}-OAc)(TPA){sub 2}]{sup 3+} (TPA = tris[(2-pyridyl)methyl]amine), 1, formed in situ at pH 4.2 from [Fe{sub 2}O({mu}-OAc)(TPA){sub 2}]{sup 3+}, 2, was embedded in an amorphous silicate surface modified by a combination of hydrophilic poly(ethylene oxide) and hydrophobic poly(propylene oxide). The resulting catalytic assembly was found to be a biomimetic model for the MMO active site within a hydrophobic macroenvironment, allowing alkane functionalization with tert-butyl hydroperoxide (TBHP)/O{sub 2} in an aqueous reaction medium (pH 4.2). For example, cyclohexane was oxidized to a mixture of cyclohexanone, cyclohexanol, and cyclohexyl-tert-butyl peroxide, in a ratio of {approximately}3:1:2. The balance between poly(ethylene oxide) and poly(propylene oxide), tethered on the silica surface, was crucial for maximizing the catalytic activity. The silica-based catalytic assembly showed reactivity somewhat higher in comparison to an aqueous micelle system utilizing the surfactant, cetyltrimethylammonium hydrogen sulfate at its critical micelle concentration, in which functionalization of cyclohexane with TBHP/O{sub 2} in the presence of 1 was also studied at pH 4.2 and was found to provide similar products: cyclohexanol, cyclohexanone, and cyclohexyl-tert-butyl peroxide, in a ratio of {approximately}2:3:1. Moreover, the mechanism for both the silica-based catalytic assembly and the aqueous micelle system was found to occur via the Haber-Weiss process, in which redox chemistry between 1 and TBHP provides both the t-BuO{sup {sm_bullet}} and t-BuOO{sup {sm_bullet}} radicals. The t-BuO{sup {sm_bullet}} radical initiates the C-H functionalization reaction to form the carbon radical, followed by O{sub 2} trapping, to provide cyclohexyl hydroperoxide, which produces the cyclohexanol and cyclohexanone in the presence of 1, whereas the coupling product emanates from t-BuOO{sup {sm_bullet}} and cyclohexyl radicals. A discussion concerning both approaches for alkane functionalization in water will be presented.

Neimann, K.; Neumann, R. [Hebrew Univ., Jerusalem (Israel); Rabion, A. [Lawrence Berkeley National Lab., CA (United States)]|[Groupement de Recherche de Lacq, Artix (France); Buchanan, R.M. [Univ. of Louisville, KY (United States). Dept. of Chemistry; Fish, R.H. [Lawrence Berkeley National Lab., CA (United States)

1999-07-26T23:59:59.000Z

390

Solid Electrolyte/Electrode Interfaces: Atomistic Behavior Analyzed Via UHV-AFM, Surface Spectroscopies, and Computer Simulations Computational and Experimental Studies of the Cathode/Electrolyte Interface in Oxide Thin Film Batteries  

DOE Green Energy (OSTI)

The goals of the research were to understand the structural, dynamic, and chemical properties of solid electrolyte surfaces and the cathode/electrolyte interface at an atomistic and nanometer level using both computational and experimental techniques.

Garofalini, Stephen H.

2012-03-21T23:59:59.000Z

391

Sulfide ceramics in molten-salt electrolyte batteries  

DOE Green Energy (OSTI)

Sulfide ceramics are finding application in the manufacture of advanced batteries with molten salt electrolyte. Use of these ceramics as a peripheral seal component has permitted development of bipolar Li/FeS{sub 2} batteries. This bipolar battery has a molten lithium halide electrolyte and operates at 400 to 450C. Initial development and physical properties evaluations indicate the ability to form metal/ceramic bonded seal (13-cm ID) components for use in high-temperature corrosive environments. These sealants are generally CaAl{sub 2}S{sub 4}-based ceramics. Structural ceramics (composites with oxide or nitride fillers), highly wetting sealant formulations, and protective coatings are also being developed. Sulfide ceramics show great promise because of their relatively low melting point, high-temperature viscous flow, chemical stability, high-strength bonding, and tailored coefficients of thermal expansion. Our methodology of generating laminated metal/ceramic pellets (e.g., molybdenum/sulfide ceramic/molybdenum) with which to optimize materials formulation and seal processing is described.

Kaun, T.D.; Hash, M.C.; Simon, D.R.

1995-06-01T23:59:59.000Z

392

Electrolytic hydrogen production infrastructure options evaluation. Final subcontract report  

DOE Green Energy (OSTI)

Fuel-cell electric vehicles have the potential to provide the range, acceleration, rapid refueling times, and other creature comforts associated with gasoline-powered vehicles, but with virtually no environmental degradation. To achieve this potential, society will have to develop the necessary infrastructure to supply hydrogen to the fuel-cell vehicles. Hydrogen could be stored directly on the vehicle, or it could be derived from methanol or other hydrocarbon fuels by on-board chemical reformation. This infrastructure analysis assumes high-pressure (5,000 psi) hydrogen on-board storage. This study evaluates one approach to providing hydrogen fuel: the electrolysis of water using off-peak electricity. Other contractors at Princeton University and Oak Ridge National Laboratory are investigating the feasibility of producing hydrogen by steam reforming natural gas, probably the least expensive hydrogen infrastructure alternative for large markets. Electrolytic hydrogen is a possible short-term transition strategy to provide relatively inexpensive hydrogen before there are enough fuel-cell vehicles to justify building large natural gas reforming facilities. In this study, the authors estimate the necessary price of off-peak electricity that would make electrolytic hydrogen costs competitive with gasoline on a per-mile basis, assuming that the electrolyzer systems are manufactured in relatively high volumes compared to current production. They then compare this off-peak electricity price goal with actual current utility residential prices across the US.

Thomas, C.E.; Kuhn, I.F. Jr. [Directed Technologies, Inc., Arlington, VA (United States)

1995-09-01T23:59:59.000Z

393

Photolysis of RDX and HMX in aqueous and organic solvents  

E-Print Network (OSTI)

Direct photolysis of high explosives (HEs) is one of the most promising alternative methods for HE disposal. The procedure is fast and safe because it accomplishes almost a complete mineralization of Hes in a very short period of time. Conventionally, the first order kinetics has been adopted to the photolytic degradation of HEs at various initial concentration and it is reported that the reaction rate also depends on the initial concentration of HEs. In this study, the kinetics of photolysis of RDX and HMX has been extensively investigated through statistical analysis. Based on two nonlinear regression results, the best kinetic model was selected, and the selected kinetic model was tested using the lack of fit test to determine whether the model had a significant amount of lack-of-fit when it was applied to empirical data. Using the selected kinetic model, solvent parameters and the initial concentration of HEs were studied to see their effects on the photolysis rate. Solution pH, buffers, ionic strength and artificial ground water, which contains many cations, were selected as aqueous solution parameters and methanol and isopropanol were chosen as organic solvents. The characteristics of photolysis products were identified using the UV absorbance spectra data of RDX and HMX. Through statistical analyses, the first order kinetic model was chosen to be the best model for the photolysis of RDX and HMX at the initial concentration of 30ppm and 20ppm respectively. Though it follows the first order kinetics, it was detected that the degradation rate depends on the initial concentration of HEs. Na?HPO?, which was used as a buffering agent, increased the photolysis rate of RDX. The first order degradation constant of RDX became high in acidic solution. Ionic strength had negative effects on the photolysis rate. The photolysis rate of RDX was slowest in AGW among all aqueous solutions, and the degradation rate of both RDX and HMX increased in organic solvents. HMX was less susceptible to the photodegradation than RDX.

Choi, Jihyun

2000-01-01T23:59:59.000Z

394

An Insoluble Titanium-Lead Anode for Sulfate Electrolytes  

SciTech Connect

The project is devoted to the development of novel insoluble anodes for copper electrowinning and electrolytic manganese dioxide (EMD) production. The anodes are made of titanium-lead composite material produced by techniques of powder metallurgy, compaction of titanium powder, sintering and subsequent lead infiltration. The titanium-lead anode combines beneficial electrochemical behavior of a lead anode with high mechanical properties and corrosion resistance of a titanium anode. In the titanium-lead anode, the titanium stabilizes the lead, preventing it from spalling, and the lead sheathes the titanium, protecting it from passivation. Interconnections between manufacturing process, structure, composition and properties of the titanium-lead composite material were investigated. The material containing 20-30 vol.% of lead had optimal combination of mechanical and electrochemical properties. Optimal process parameters to manufacture the anodes were identified. Prototypes having optimized composition and structure were produced for testing in operating conditions of copper electrowinning and EMD production. Bench-scale, mini-pilot scale and pilot scale tests were performed. The test anodes were of both a plate design and a flow-through cylindrical design. The cylindrical anodes were composed of cylinders containing titanium inner rods and fitting over titanium-lead bushings. The cylindrical design allows the electrolyte to flow through the anode, which enhances diffusion of the electrolyte reactants. The cylindrical anodes demonstrate higher mass transport capabilities and increased electrical efficiency compared to the plate anodes. Copper electrowinning represents the primary target market for the titanium-lead anode. A full-size cylindrical anode performance in copper electrowinning conditions was monitored over a year. The test anode to cathode voltage was stable in the 1.8 to 2.0 volt range. Copper cathode morphology was very smooth and uniform. There was no measurable anode weight loss during this time period. Quantitative chemical analysis of the anode surface showed that the lead content after testing remained at its initial level. No lead dissolution or transfer from the anode to the product occurred.A key benefit of the titanium-lead anode design is that cobalt additions to copper electrolyte should be eliminated. Cobalt is added to the electrolyte to help stabilize the lead oxide surface of conventional lead anodes. The presence of the titanium intimately mixed with the lead should eliminate the need for cobalt stabilization of the lead surface. The anode should last twice as long as the conventional lead anode. Energy savings should be achieved due to minimizing and stabilizing the anode-cathode distance in the electrowinning cells. The anode is easily substitutable into existing tankhouses without a rectifier change.The copper electrowinning test data indicate that the titanium-lead anode is a good candidate for further testing as a possible replacement for a conventional lead anode. A key consideration is the cost. Titanium costs have increased. One of the ways to get the anode cost down is manufacturing the anodes with fewer cylinders. Additional prototypes having different number of cylinders were constructed for a long-term commercial testing in a circuit without cobalt. The objective of the testing is to evaluate the need for cobalt, investigate the effect of decreasing the number of cylinders on the anode performance, and to optimize further the anode design in order to meet the operating requirements, minimize the voltage, maximize the life of the anode, and to balance this against a reasonable cost for the anode. It is anticipated that after testing of the additional prototypes, a whole cell commercial test will be conducted to complete evaluation of the titanium-lead anode costs/benefits.

Ferdman, Alla

2005-05-11T23:59:59.000Z

395

Low temperature aqueous desulfurization of coal  

DOE Patents (OSTI)

This invention describes a chemical process for desulfurizing coal, especially adaptable to the treatment of coal-water slurries, at temperatures as low as ambient, comprising treating the coal with aqueous titanous chloride whereby hydrogen sulfide is liberated and the desulfurized coal is separated with the conversion of titanous chloride to titanium oxides.

Slegeir, William A. (Hampton Bays, NY); Healy, Francis E. (Massapequa, NY); Sapienza, Richard S. (Shoreham, NY)

1985-01-01T23:59:59.000Z

396

Corrosion inhibitor for aqueous ammonia absorption system  

DOE Patents (OSTI)

A method of inhibiting corrosion and the formation of hydrogen and thus improving absorption in an ammonia/water absorption refrigeration, air conditioning or heat pump system by maintaining the hydroxyl ion concentration of the aqueous ammonia working fluid within a selected range under anaerobic conditions at temperatures up to 425.degree. F. This hydroxyl ion concentration is maintained by introducing to the aqueous ammonia working fluid an inhibitor in an amount effective to produce a hydroxyl ion concentration corresponding to a normality of the inhibitor relative to the water content ranging from about 0.015 N to about 0.2 N at 25.degree. C. Also, working fluids for inhibiting the corrosion of carbon steel and resulting hydrogen formation and improving absorption in an ammonia/water absorption system under anaerobic conditions at up to 425.degree. F. The working fluids may be aqueous solutions of ammonia and a strong base or aqueous solutions of ammonia, a strong base, and a specified buffer.

Phillips, Benjamin A. (Benton Harbor, MI); Whitlow, Eugene P. (St. Joseph, MI)

1998-09-22T23:59:59.000Z

397

Corrosion inhibitor for aqueous ammonia absorption system  

DOE Patents (OSTI)

A method is described for inhibiting corrosion and the formation of hydrogen and thus improving absorption in an ammonia/water absorption refrigeration, air conditioning or heat pump system by maintaining the hydroxyl ion concentration of the aqueous ammonia working fluid within a selected range under anaerobic conditions at temperatures up to 425 F. This hydroxyl ion concentration is maintained by introducing to the aqueous ammonia working fluid an inhibitor in an amount effective to produce a hydroxyl ion concentration corresponding to a normality of the inhibitor relative to the water content ranging from about 0.015 N to about 0.2 N at 25 C. Also, working fluids for inhibiting the corrosion of carbon steel and resulting hydrogen formation and improving absorption in an ammonia/water absorption system under anaerobic conditions at up to 425 F. The working fluids may be aqueous solutions of ammonia and a strong base or aqueous solutions of ammonia, a strong base, and a specified buffer. 5 figs.

Phillips, B.A.; Whitlow, E.P.

1998-09-22T23:59:59.000Z

398

Water & Aqueous Solutions. Final Progress Report  

SciTech Connect

The Gordon Research Conference (GRC) on Water & Aqueous Solutions was held at Holderness School, New Hampshire, 8/4/02 thru 8/9/02. Emphasis was placed on current unpublished research and discussion of the future target areas in this field.

2002-08-09T23:59:59.000Z

399

Method for aqueous radioactive waste treatment  

DOE Patents (OSTI)

Plutonium, strontium, and cesium found in aqueous waste solutions resulting from nuclear fuel processing are removed by contacting the waste solutions with synthetic zeolite incorporating up to about 5 wt % titanium as sodium titanate in an ion exchange system. More than 99.9% of the plutonium, strontium, and cesium are removed from the waste solutions. 3 figures.

Bray, L.A.; Burger, L.L.

1994-03-29T23:59:59.000Z

400

Method for aqueous radioactive waste treatment  

DOE Patents (OSTI)

Plutonium, strontium, and cesium found in aqueous waste solutions resulting from nuclear fuel processing are removed by contacting the waste solutions with synthetic zeolite incorporating up to about 5 wt % titanium as sodium titanate in an ion exchange system. More than 99.9% of the plutonium, strontium, and cesium are removed from the waste solutions.

Bray, Lane A. (Richland, WA); Burger, Leland L. (Richland, WA)

1994-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "aqueous electrolyte modeling" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Low temperature aqueous desulfurization of coal  

DOE Patents (OSTI)

This invention describes a chemical process for desulfurizing coal, especially adaptable to the treatment of coal-water slurries, at temperatures as low as ambient, comprising treating the coal with aqueous titanous chloride whereby hydrogen sulfide is liberated and the desulfurized coal is separated with the conversion of titanous chloride to titanium oxides.

Slegeir, W.A.; Healy, F.E.; Sapienza, R.S.

1985-04-18T23:59:59.000Z

402

Inhibition of Lithium Dendrites by Fumed Silica-Based Composite Electrolytes  

E-Print Network (OSTI)

Inhibition of Lithium Dendrites by Fumed Silica-Based Composite Electrolytes Xiang-Wu Zhang State University, Raleigh, North Carolina 27695-7905, USA Lithium dendrite formation is investigated via in situ microscopy in a liquid electrolyte containing polyethylene glycol dimethyl ether lithium bis

Khan, Saad A.

403

Method for producing electricity from a fuel cell having solid-oxide ionic electrolyte  

DOE Patents (OSTI)

Stabilized quadrivalent cation oxide electrolytes are employed in fuel cells at elevated temperatures with a carbon and/or hydrogen containing fuel anode and an oxygen cathode. The fuel cell is operated at elevated temperatures with conductive metallic coatings as electrodes and desirably having the electrolyte surface blackened. Of particular interest as the quadrivalent oxide is zirconia.

Mason, David M. (Los Altos, CA)

1984-01-01T23:59:59.000Z

404

Performance of Polymer Electrolyte Membrane Fuel Cell Based on New Polymeric Ionomers  

Science Conference Proceedings (OSTI)

In this paper, novel polymer electrolyte membranes (PEMs) based on new sulfonated polyimides have been prepared. These polymers have structure of rigid aromatic polymer backbone and flexible aliphatic side chain terminated with sulfonic acid group. Membrane ... Keywords: PEM fuel cell, polymer electrolyte membrane, proton conductivity, fuel cell performance

Yan Yin; Qing Du; Kenichi Okamoto

2010-12-01T23:59:59.000Z

405

ESS 2012 Peer Review - Organic and Inorganic Solid Electrolytes for Li-ion Batteries - Nader Hagh, NEI Corporation  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Organic and Inorganic Solid Electrolytes for Li-ion Batteries Organic and Inorganic Solid Electrolytes for Li-ion Batteries Background & Objectives * Lithium ion batteries widely used in consumer applications Solvent leakage and flammability of conventional liquid electrolytes * Current solid state electrolytes suffer from low ionic conductivity, inferior rate capability, and interfacial instability * Objective of the program is to develop solid state organic and inorganic electrolyte that has enhanced ionic conductivity * PEO based polymer electrolyte has poor room ionic conductivity due to crystallinity * The current program develops a PEO based hybrid copolymer that disrupts crystallization and at the same time provides mechanical integrity Abstract: The use of a solid polymer electrolyte instead of the conventional liquid or gel electrolyte can drastically improve the safety

406

Stabilization of Nickel Metal Catalysts for Aqueous Processing ...  

Search PNNL. PNNL Home; About; Research; Publications; Jobs; News; Contacts; Stabilization of Nickel Metal Catalysts for Aqueous Processing Systems. ...

407

Process and apparatus for the electrolytic production of hydrogen  

SciTech Connect

An electrolyzer is claimed for an alkaline aqueous solution and having an anode and a cathode where at least the cathode is made of a ternary alloy of nickel--beryllium--titanium, the proportions of beryllium and titanium being respectively 1 to 3% and 0.1 to 1% by weight. The electrolyzer is preferaly used at temperatures above 110/sup 0/C and at high current densities.

Verger, B.; Demange, P.

1979-05-15T23:59:59.000Z

408

Extraction of Biofuels and Biofeedstocks from Aqueous Solutions Using Ionic Liquids  

E-Print Network (OSTI)

Extraction of Biofuels and Biofeedstocks from Aqueous Solutions Using Ionic Liquids Luke D. Simoni-Butanol, Extraction, Liquid-Liquid Equilibrium, Excess Gibbs Energy Models, Biofuels #12;1 1. Introduction other organic compounds can be produced biologically, and thus can be considered as biofuel candidates

Stadtherr, Mark A.

409

Electrical contact structures for solid oxide electrolyte fuel cell  

DOE Patents (OSTI)

An improved electrical output connection means is provided for a high temperature solid oxide electrolyte type fuel cell generator. The electrical connection of the fuel cell electrodes to the electrical output bus, which is brought through the generator housing to be connected to an electrical load line maintains a highly uniform temperature distribution. The electrical connection means includes an electrode bus which is spaced parallel to the output bus with a plurality of symmetrically spaced transversely extending conductors extending between the electrode bus and the output bus, with thermal insulation means provided about the transverse conductors between the spaced apart buses. Single or plural stages of the insulated transversely extending conductors can be provided within the high temperatures regions of the fuel cell generator to provide highly homogeneous temperature distribution over the contacting surfaces.

Isenberg, Arnold O. (Forest Hills, PA)

1984-01-01T23:59:59.000Z

410

Pyrochemical process for extracting plutonium from an electrolyte salt  

DOE Patents (OSTI)

A pyrochemical process for extracting plutonium from a plutonium-bearing salt is disclosed. The process is particularly useful in the recovery of plutonium from electrolyte salts which are left over from the electrorefining of plutonium. In accordance with the process, the plutonium-bearing salt is melted and mixed with metallic calcium. The calcium reduces ionized plutonium in the salt to plutonium metal, and also causes metallic plutonium in the salt, which is typically present as finely dispersed metallic shot, to coalesce. The reduced and coalesced plutonium separates out on the bottom of the reaction vessel as a separate metallic phase which is readily separable from the overlying salt upon cooling of the mixture. Yields of plutonium are typically on the order of 95%. The stripped salt is virtually free of plutonium and may be discarded to low-level waste storage.

Mullins, Lawrence J. (Los Alamos, NM); Christensen, Dana C. (Los Alamos, NM)

1984-01-01T23:59:59.000Z

411

Electra-optical device including a nitrogen containing electrolyte  

DOE Patents (OSTI)

Described is a thin-film battery, especially a thin-film microbattery, and a method for making same having application as a backup or primary integrated power source for electronic devices. The battery includes a novel electrolyte which is electrochemically stable and does not react with the lithium anode and a novel vanadium oxide cathode. Configured as a microbattery, the battery can be fabricated directly onto a semiconductor chip, onto the semiconductor die or onto any portion of the chip carrier. The battery can be fabricated to any specified size or shape to meet the requirements of a particular application. The battery is fabricated of solid state materials and is capable of operation between {minus}15 C and 150 C.

Bates, J.B.; Dudney, N.J.; Gruzalski, G.R.; Luck, C.F.

1995-10-03T23:59:59.000Z

412

Method of making an electrolyte for an electrochemical cell  

DOE Patents (OSTI)

Described is a thin-film battery, especially a thin-film microbattery, and a method for making same having application as a backup or primary integrated power source for electronic devices. The battery includes a novel electrolyte which is electrochemically stable and does not react with the lithium anode and a novel vanadium oxide cathode. Configured as a microbattery, the battery can be fabricated directly onto a semiconductor chip, onto the semiconductor die or onto any portion of the chip carrier. The battery can be fabricated to any specified size or shape to meet the requirements of a particular application. The battery is fabricated of solid state materials and is capable of operation between {minus}15 C and 150 C. 9 figs.

Bates, J.B.; Dudney, N.J.

1996-04-30T23:59:59.000Z

413

Surface Tension of Electrolyte Solutions: A Self-consistent Theory  

E-Print Network (OSTI)

We study the surface tension of electrolyte solutions at the air/water and oil/water interfaces. Employing field-theoretical methods, and considering short-range interactions of anions with the surface, we expand the Helmholtz free energy to first-order in a loop expansion and calculate self-consistently the excess surface tension. We obtain analytically the surface-tension dependence on the ionic strength, ionic size and ion-surface interaction, as a direct generalization of the well-known Onsager-Samaras theory. Our theory fits well a wide range of concentrations for different salts using two fit parameters, reproducing the reverse Hofmeister series for anions at the air/water and oil/water interfaces.

Markovich, Tomer; Podgornik, Rudi

2013-01-01T23:59:59.000Z

414

Short protection device for stack of electrolytic cells  

DOE Patents (OSTI)

Electrical short protection is provided in an electrolytic cell stack by the combination of a thin, nonporous ceramic shield and a noble metal foil disposed on opposite sides of the sealing medium in a gas manifold gasket. The thin ceramic shield, such as alumina, is placed between the porous gasket and the cell stack face at the margins of the negative end plate to the most negative cells to impede ion current flow. The noble metal foil, for instance gold, is electrically coupled to the negative potential of the stack to collect positive ions at a harmless location away from the stack face. Consequently, corrosion products from the stack structure deposit on the foil rather than on the stack face to eliminate electrical shorting of cells at the negative end of the stack.

Katz, Murray (Newington, CT); Schroll, Craig R. (West Hartford, CT)

1985-10-22T23:59:59.000Z

415

PRODUCTION OF HEAVY WATER BY THE ELECTROLYTIC METHOD  

SciTech Connect

Two cell designs were tried for the production of high concentration heavy water. Iron was used as an electrode in both designs. The rectangular cell measured 38 cm x 54 cm x 24 cm and the cylindrical cell was 42 cm tall and 11 cm in diameter. The over-all current used was 150 amperes during the day and 75 amperes during the night (the current density on the electrodes was not given). The explosive hydrogen and oxygen mixture was passed through copper oxide kept at the optimum temperature for catalyzing the recombination of the gases into water. After six months of operation 20 cc each of 97% and 98% D/sub 2/O were obtained; the electrolytic separation coefficient was, throughout, approximately 5. (TTT)

Tai, Y.; Hsu, Y.

1960-01-01T23:59:59.000Z

416

Electra-optical device including a nitrogen containing electrolyte  

SciTech Connect

Described is a thin-film battery, especially a thin-film microbattery, and a method for making same having application as a backup or primary integrated power source for electronic devices. The battery includes a novel electrolyte which is electrochemically stable and does not react with the lithium anode and a novel vanadium oxide cathode Configured as a microbattery, the battery can be fabricated directly onto a semiconductor chip, onto the semiconductor die or onto any portion of the chip carrier. The battery can be fabricated to any specified size or shape to meet the requirements of a particular application. The battery is fabricated of solid state materials and is capable of operation between -15.degree. C. and 150.degree. C.

Bates, John B. (Oak Ridge, TN); Dudney, Nancy J. (Knoxville, TN); Gruzalski, Greg R. (Oak Ridge, TN); Luck, Christopher F. (Knoxville, TN)

1995-01-01T23:59:59.000Z

417

Method of making an electrolyte for an electrochemical cell  

SciTech Connect

Described is a thin-film battery, especially a thin-film microbattery, and a method for making same having application as a backup or primary integrated power source for electronic devices. The battery includes a novel electrolyte which is electrochemically stable and does not react with the lithium anode and a novel vanadium oxide cathode Configured as a microbattery, the battery can be fabricated directly onto a semiconductor chip, onto the semiconductor die or onto any portion of the chip carrier. The battery can be fabricated to any specified size or shape to meet the requirements of a particular application. The battery is fabricated of solid state materials and is capable of operation between -15.degree. C. and 150.degree. C.

Bates, John B. (Oak Ridge, TN); Dudney, Nancy J. (Knoxville, TN)

1996-01-01T23:59:59.000Z

418

Pyrochemical process for extracting plutonium from an electrolyte salt  

DOE Patents (OSTI)

A pyrochemical process for extracting plutonium from a plutonium-bearing salt is disclosed. The process is particularly useful in the recovery of plutonium for electrolyte salts which are left over from the electrorefining of plutonium. In accordance with the process, the plutonium-bearing salt is melted and mixed with metallic calcium. The calcium reduces ionized plutonium in the salt to plutonium metal, and also causes metallic plutonium in the salt, which is typically present as finely dispersed metallic shot, to coalesce. The reduced and coalesced plutonium separates out on the bottom of the reaction vessel as a separate metallic phase which is readily separable from the overlying salt upon cooling of the mixture. Yields of plutonium are typically on the order of 95%. The stripped salt is virtually free of plutonium and may be discarded to low-level waste storage.

Mullins, L.J.; Christensen, D.C.

1982-09-20T23:59:59.000Z

419

The Stirred Tank Reactor Polymer Electrolyte Membrane Fuel Cell  

E-Print Network (OSTI)

The design and operation of a differential Polymer Electrolyte Membrane (PEM) fuel cell is described. The fuel cell design is based on coupled Stirred Tank Reactors (STR); the gas phase in each reactor compartment was well mixed. The characteristic times for reactant flow, gas phase diffusion and reaction were chosen so that the gas compositions at both the anode and cathode are uniform. The STR PEM fuel cell is one-dimensional; the only spatial gradients are transverse to the membrane. The STR PEM fuel cell was employed to examine fuel cell start- up, and its dynamic responses to changes in load, temperature and reactant flow rates. Multiple time scales in systems response are found to correspond to water absorption by the membrane, water transport through the membrane and stress-related mechanical changes of the membrane.

Benziger, J; Karnas, E; Moxley, J; Teuscher, C; Kevrekidis, Yu G; Benziger, Jay

2003-01-01T23:59:59.000Z

420

Surface Tension of Electrolyte Solutions: A Self-consistent Theory  

E-Print Network (OSTI)

We study the surface tension of electrolyte solutions at the air/water and oil/water interfaces. Employing field-theoretical methods, and considering short-range interactions of anions with the surface, we expand the Helmholtz free energy to first-order in a loop expansion and calculate self-consistently the excess surface tension. We obtain analytically the surface-tension dependence on the ionic strength, ionic size and ion-surface interaction, as a direct generalization of the well-known Onsager-Samaras theory. Our theory fits well a wide range of concentrations for different salts using two fit parameters, reproducing the reverse Hofmeister series for anions at the air/water and oil/water interfaces.

Tomer Markovich; David Andelman; Rudi Podgornik

2013-05-14T23:59:59.000Z

Note: This page contains sample records for the topic "aqueous electrolyte modeling" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Bubble coalescence dynamics and supersaturation in electrolytic gas evolution  

SciTech Connect

The apparatus and procedures developed in this research permit the observation of electrolytic bubble coalescence, which heretofore has not been possible. The influence of bubble size, electrolyte viscosity, surface tension, gas type, and pH on bubble coalescence was examined. The Navier-Stokes equations with free surface boundary conditions were solved numerically for the full range of experimental variables that were examined. Based on this study, the following mechanism for bubble coalescence emerges: when two gas bubbles coalesce, the surface energy decreases as the curvature and surface area of the resultant bubble decrease, and the energy is imparted into the surrounding liquid. The initial motion is driven by the surface tension and slowed by the inertia and viscosity of the surrounding fluid. The initial velocity of the interface is approximately proportional to the square root of the surface tension and inversely proportional to the square root of the bubble radius. Fluid inertia sustains the oblate/prolate oscillations of the resultant bubble. The period of the oscillations varies with the bubble radius raised to the 3/2 power and inversely with the square root of the surface tension. Viscous resistance dampens the oscillations at a rate proportional to the viscosity and inversely proportional to the square of the bubble radius. The numerical simulations were consistent with most of the experimental results. The differences between the computed and measured saddle point decelerations and periods suggest that the surface tension in the experiments may have changed during each run. By adjusting the surface tension in the simulation, a good fit was obtained for the 150-{micro}m diameter bubbles. The simulations fit the experiments on larger bubbles with very little adjustment of surface tension. A more focused analysis should be done to elucidate the phenomena that occur in the receding liquid film immediately following rupture.

Stover, R.L. [Univ. of California, Berkeley, CA (United States). Dept. of Chemical Engineering]|[Lawrence Berkeley National Lab., CA (United States). Energy and Environment Div.

1996-08-01T23:59:59.000Z

422

Radiotracer Dilution Method for Mercury Inventory Study in Electrolytic Cells  

Science Conference Proceedings (OSTI)

Purpose of the experiment is to demonstrate feasibility the use of radiotracer to measure weight of mercury in electrolytic cells of soda industry. The weight of mercury in each cell of the plant is designed approximately 1700 kg. Radiotracer is prepared by mixing {sup 203}Hg radioactive mercury with 2400 g of inactive mercury in a bath. The respective precisely weighted mercury aliquots to be injected into the cells are prepared by pouring approximately 130 g of radioactive mercury taken from the bath into 13 standard vials, in accordance with the number of the cells tested. Four standard references prepared by further dilution of {+-}2 g active mercury taken from the bath to obtain the dilution factors range of 12,000 to 20,000 from which the calibration graph is constructed. The injection process is conducting by pouring the radioactive mercury from aliquots into the flowing mercury at the inlet side of the cell and allows them to mix thoroughly. It is assumed that the mass of the radiotracer injected into a closed system remains constant, at least during the period of the test. From this experiment it was observed that the mixing time is two days after injection of radioactive mercury. The inactive mercury in each electrolytic cell calculated by the radiotracer method is of the range 1351.529 kg to 1966.354 kg with maximum error (95% confidence) is 1.52 %. The accuracy of measurement of the present method is better than gravimetric one which accounts 4 % of error on average.

Sugiharto [Department of Physics, Faculty of Mathematics and Natural Sciences, Bandung Institute of Technology, Jl. Ganesha 10, Bandung 40132 (Indonesia); Centre for Application of Isotopes and Radiation Technology, National Nuclear Energy Agency, Jl. Lebak Bulus Raya No 49, Jakarta 12440 (Indonesia); Su'ud, Zaki; Kurniadi, Rizal; Waris, Abdul [Department of Physics, Faculty of Mathematics and Natural Sciences, Bandung Institute of Technology, Jl. Ganesha 10, Bandung 40132 (Indonesia); Santoso, Sigit Budi; Abidin, Zainal [Centre for Application of Isotopes and Radiation Technology, National Nuclear Energy Agency, Jl. Lebak Bulus Raya No 49, Jakarta 12440 (Indonesia); Santoso, Gatot Budi [PT. Industri Soda Indonesia, Jl. Raya Waru 31, Sidoarjo 61256 (Indonesia)

2010-06-22T23:59:59.000Z

423

Novel concepts in electrochemical solar cells. Second quarterly progress report, August 15, 1979-October 15, 1979. [Molten salt electrolytes  

DOE Green Energy (OSTI)

It is considered that the short term stability of n-GaAs PEC's in a ferrocene-based, ambient temperature molten salt electrolyte is reasonably good. However, longer term evaluation is required to determine the extent and significance of corrosion, stability, etc. Extremely few fundamental studies have been made of the semiconductor/molten salt interphase and experiments in this area would be most useful. Indeed, even the design parameters for PECs of any kind have not been quantitatively delineated and present consideration will be given to models for PEC solar cells and limitations caused by ion transport in the electrolyte. The MoSe/sub 2/ and MoS/sub 2/ electrodes appear to have substrate reproducibility and transport limitations that make them unsuitable candidates for efficient PEC's at this time. Similarly, the lack of availability of high quality CuInSe/sub 2/ and CuInS/sub 2/ substrates limits the quantitative experimental evaluation of their utility for PEC applications. We are presently focusing attention on CdSe/CdTe mixtures and CdS as electrodes as well as Si and GaAs in molten salt and polyelectrolyte solutions. The system for solar cell evaluation and network analysis of substrates and cells was mode operational. Preliminary work on economic and theoretical modelling was begun. Progress is reported. (WHK)

DuBow, J.; Job, R.; Krishnan, R.; Gale, B.

1979-01-01T23:59:59.000Z

424

Removal of metal ions from aqueous solution  

DOE Patents (OSTI)

A method of removing heavy metals from aqueous solution, a composition of matter used in effecting said removal, and apparatus used in effecting said removal. One or more of the polypeptides, poly ({gamma}-glutamylcysteinyl)glycines, is immobilized on an inert material in particulate form. Upon contact with an aqueous solution containing heavy metals, the polypeptides sequester the metals, removing them from the solution. There is selectivity of poly ({gamma}-glutamylcysteinyl)glycines having a particular number of monomer repeat units for particular metals. The polypeptides are easily regenerated by contact with a small amount of an organic acid, so that they can be used again to remove heavy metals from solution. This also results in the removal of the metals from the column in a concentrated form.

Jackson, P.J.; Delhaize, E.; Robinson, N.J.; Unkefer, C.J.; Furlong, C.

1988-08-26T23:59:59.000Z

425

Aqueous flooding methods for tertiary oil recovery  

DOE Patents (OSTI)

A method of aqueous flooding of subterranean oil bearing formation for tertiary oil recovery involves injecting through a well into the formation a low alkaline pH aqueous sodium bicarbonate flooding solution. The flooding solution's pH ranges from about 8.25 to 9.25 and comprises from 0.25 to 5 weight percent and preferably about 0.75 to 3.0 weight percent of sodium bicarbonate and includes a petroleum recovery surfactant of 0.05 to 1.0 weight percent and between 1 and 20 weight percent of sodium chloride. After flooding, an oil and water mixture is withdrawn from the well and the oil is separated from the oil and water mixture.

Peru, Deborah A. (Bartlesville, OK)

1989-01-01T23:59:59.000Z

426

Removal of metal ions from aqueous solution  

DOE Patents (OSTI)

A method of removing heavy metals from aqueous solution, a composition of matter used in effecting said removal, and apparatus used in effecting said removal. One or more of the polypeptides, poly (.gamma.-glutamylcysteinyl)glycines, is immobilized on an inert material in particulate form. Upon contact with an aqueous solution containing heavy metals, the polypeptides sequester the metals, removing them from the solution. There is selectivity of poly (.gamma.-glutamylcysteinyl)glycines having a particular number of monomer repeat units for particular metals. The polypeptides are easily regenerated by contact with a small amount of an organic acid, so that they can be used again to remove heavy metals from solution. This also results in the removal of the metals from the column in a concentrated form.

Jackson, Paul J. (Los Alamos, NM); Delhaize, Emmanuel (Los Alamos, NM); Robinson, Nigel J. (Durham, GB2); Unkefer, Clifford J. (Los Alamos, NM); Furlong, Clement (Seattle, WA)

1990-01-01T23:59:59.000Z

427

Removal of metal ions from aqueous solution  

DOE Patents (OSTI)

A method of removing heavy metals from aqueous solution, a composition of matter used in effecting said removal, and apparatus used in effecting said removal. One or more of the polypeptides, poly (.gamma.-glutamylcysteinyl)glycines, is immobilized on an inert material in particulate form. Upon contact with an aqueous solution containing heavy metals, the polypeptides sequester the metals, removing them from the solution. There is selectivity of poly (.gamma.-glutamylcysteinyl)glycines having a particular number of monomer repeat unit for particular metals. The polypeptides are easily regenerated by contact with a small amount of an organic acid, so that they can be used again to remove heayv metals from solution. This also results in the removal of the metals from the column in a concentrated form.

Jackson, Paul J. (both Los Alamos, NM); Delhaize, Emmanuel (both Los Alamos, NM); Robinson, Nigel J. (Durham, GB2); Unkefer, Clifford J. (Los Alamos, NM); Furlong, Clement (Seattle, WA)

1990-11-13T23:59:59.000Z

428

Behavior of americium in aqueous carbonate systems  

Science Conference Proceedings (OSTI)

The solubilities of crystalline Am(OH)/sub 3/ and AmOHCO/sub 3/ were measured at 25/sup 0/C in aqueous solutions of 0.1 M NaClO/sub 4/ by determination of the solution concentrations of Am. Prior to use in the measurements, the solid materials were characterized by their x-ray powder diffraction patterns. The solubility product quotients were calculated from the experimental data. The hydrolysis quotients of Am/sup 3 +/ were also estimated from the hydroxide solubility data. Using the thermodynamic data derived from these experiments and the recently reported formation constants for the Am/sup 3 +/ carbonate complexes, the solid phases and concentrations of solution species of americium in several aqueous carbonate systems were calculated using the computer code MINEQL. 20 references, 1 figure, 1 table.

Silva, R.J.

1983-11-01T23:59:59.000Z

429

Design, integration, and trade-off analyses of gasoline-fueled polymer electrolyte fuel cell systems for transportation.  

DOE Green Energy (OSTI)

Prototype fuel-cell-powered vehicles have recently been demonstrated in Japan, Europe, and North America. Conceptual designs and simulations of fuel-cell-powered vehicles have also been published [1-3]. Many of these simulations include detailed vehicle performance models, but they use relatively simplistic fuel-cell power system models. We have developed a comprehensive model of a polymer electrolyte fuel cell (PEFC) power system for automotive propulsion. This system simulation has been used to design and analyze fuel-cell systems and vehicles with gasoline (or other hydrocarbons) as the on-board fuel. The major objective of this analysis is to examine the influence of design parameters on system efficiency and performance, and component sizes.

Kumar, R.

1998-09-14T23:59:59.000Z

430

Thin-film electrolytes for reduced temperature solid oxide fuel cells  

DOE Green Energy (OSTI)

Solid oxide fuel cells produce electricity at very high efficiency and have very low to negligible emissions, making them an attractive option for power generation for electric utilities. However, conventional SOFC`s are operated at 1000{degrees}C or more in order to attain reasonable power density. The high operating temperature of SOFC`s leads to complex materials problems which have been difficult to solve in a cost-effective manner. Accordingly, there is much interest in reducing the operating temperature of SOFC`s while still maintaining the power densities achieved at high temperatures. There are several approaches to reduced temperature operation including alternative solid electrolytes having higher ionic conductivity than yttria stabilized zirconia, thin solid electrolyte membranes, and improved electrode materials. Given the proven reliability of zirconia-based electrolytes (YSZ) in long-term SOFC tests, the use of stabilized zirconia electrolytes in reduced temperature fuel cells is a logical choice. In order to avoid compromising power density at intermediate temperatures, the thickness of the YSZ electrolyte must be reduced from that in conventional cells (100 to 200 {mu}m) to approximately 4 to 10 {mu}m. There are a number of approaches for depositing thin ceramic films onto porous supports including chemical vapor deposition/electrochemical vapor deposition, sol-gel deposition, sputter deposition, etc. In this paper we describe an inexpensive approach involving the use of colloidal dispersions of polycrystalline electrolyte for depositing 4 to 10 {mu}m electrolyte films onto porous electrode supports in a single deposition step. This technique leads to highly dense, conductive, electrolyte films which exhibit near theoretical open circuit voltages in H{sub 2}/air fuel cells. These electrolyte films exhibit bulk ionic conductivity, and may see application in reduced temperature SOFC`s, gas separation membranes, and fast response sensors.

Visco, S.J.; Wang, L.S.; De Souza, S.; De Jonghe, L.C.

1994-11-01T23:59:59.000Z

431

Electrolytic electrodes having high durability and process for the production of same  

SciTech Connect

An electrolytic electrode having high durability for use in electrolysis where the generation of oxygen occurs, and a process for the production of the electrolytic electrode are disclosed. The electrolytic electrode comprises: an electrode substrate of titanium or a titanium-based alloy; an electrode coating of a metal oxide; and an intermediate layer comprising an electrically conductive oxide of tantalum and/or niobium, provided between the electrode substrate and the electrode coating, in a thickness calculated as the metal, of 0.001 to 2 g/m/sup 2/.

Asano, H.; Nitta, H.; Shimamune, T.

1984-08-28T23:59:59.000Z

432

Photographic study of the mechanism of heat transfer enhancement by electrolytic hydrogen gas  

SciTech Connect

A mechanism of promoting heat transfer, by which a remarkably high heat flux is obtained with a heat source having a small temperature difference is elucidated. The method consists of generating a small amount of electrolytic hydrogen gas from a heating surface undergoing nucleate boiling and natural convection. Photographs of a boiling process in the presence of electrolytic hydrogen gas evolution from the heating surface were taken. By analyzing high-speed motion pictures it is shown that the electrolytic hydrogen gas permits vapor bubble production with a small degree of superheat and increases the number of vapor bubble nuclei.

Nakayama, A.; Kano, M.

1983-06-01T23:59:59.000Z

433

Non-consumable anode and lining for aluminum electrolytic reduction cell  

DOE Patents (OSTI)

An oxidation resistant, non-consumable anode, for use in the electrolytic reduction of alumina to aluminum, has a composition comprising copper, nickel and iron. The anode is part of an electrolytic reduction cell comprising a vessel having an interior lined with metal which has the same composition as the anode. The electrolyte is preferably composed of a eutectic of AlF.sub.3 and either (a) NaF or (b) primarily NaF with some of the NaF replaced by an equivalent molar amount of KF or KF and LiF.

Beck, Theodore R. (Seattle, WA); Brooks, Richard J. (Seattle, WA)

1994-01-01T23:59:59.000Z

434

Method for treating electrolyte to remove Li.sub.2 O  

DOE Patents (OSTI)

A method of removing Li.sub.2 O present in an electrolyte predominantly of LiCl and KCl. The electrolyte is heated to a temperature not less than about 500.degree. C. and then Al is introduced into the electrolyte in an amount in excess of the stoichiometric amount needed to convert the Li.sub.2 O to a Li-Al alloy and lithium aluminate salt. The salt and aluminum are maintained in contact with agitation for a time sufficient to convert the Li.sub.2 O.

Tomczuk, Zygmunt (Lockport, IL); Miller, William E. (Naperville, IL); Johnson, Gerald K. (Downers Grove, IL); Willit, James L. (Batavia, IL)

1998-01-01T23:59:59.000Z

435

Method for treating electrolyte to remove Li{sub 2}O  

DOE Patents (OSTI)

A method is described for removing Li{sub 2}O present in an electrolyte predominantly of LiCl and KCl. The electrolyte is heated to a temperature not less than about 500 C and then Al is introduced into the electrolyte in an amount in excess of the stoichiometric amount needed to convert the Li{sub 2}O to a Li-Al alloy and lithium aluminate salt. The salt and aluminum are maintained in contact with agitation for a time sufficient to convert the Li{sub 2}O.

Tomczuk, Z.; Miller, W.E.; Johnson, G.K.; Willit, J.L.

1998-01-20T23:59:59.000Z

436

Heat and water transport in a polymer electrolyte fuel cell electrode  

SciTech Connect

In the present scenario of a global initiative toward a sustainable energy future, the polymer electrolyte fuel cell (PEFC) has emerged as one of the most promising alternative energy conversion devices for various applications. Despite tremendous progress in recent years, a pivotal performance limitation in the PEFC comes from liquid water transport and the resulting flooding phenomena. Liquid water blocks the open pore space in the electrode and the fibrous diffusion layer leading to hindered oxygen transport. The electrode is also the only component in the entire PEFC sandwich which produces waste heat from the electrochemical reaction. The cathode electrode, being the host to several competing transport mechanisms, plays a crucial role in the overall PEFC performance limitation. In this work, an electrode model is presented in order to elucidate the coupled heat and water transport mechanisms. Two scenarios are specifically considered: (1) conventional, Nafion{reg_sign} impregnated, three-phase electrode with the hydrated polymeric membrane phase as the conveyer of protons where local electro-neutrality prevails; and (2) ultra-thin, two-phase, nano-structured electrode without the presence of ionomeric phase where charge accumulation due to electro-statics in the vicinity of the membrane-CL interface becomes important. The electrode model includes a physical description of heat and water balance along with electrochemical performance analysis in order to study the influence of electro-statics/electro-migration and phase change on the PEFC electrode performance.

Mukherjee, Partha P [Los Alamos National Laboratory; Mukundan, Rangachary [Los Alamos National Laboratory; Borup, Rod L [Los Alamos National Laboratory; Ranjan, Devesh [TEXAS A& M UNIV

2010-01-01T23:59:59.000Z

437

Freezing and sorption/desorption of water confined in a Polymeric Electrolyte Membrane  

E-Print Network (OSTI)

Nafion is a perfluorosulfonated polymer, widely used in Proton Exchange Membrane Fuel Cells. This amphiphilic polymer adopts a structural organisation made of channels and cavities formed by the organisation of the sulfonate groups. Upon hydration, the cavities are filled with water in which are released the acidic protons to form a solution of hydronium ions in water, confined in the polymer matrix. Below 0OC, a phenomenon of water sorption/desorption occurs, whose origin is still an open question. Performing neutron diffraction, we monitored the quantity of ice formed during the sorption/desorption as a function of temperature down to 180 K. Upon cooling, we observe that ice forms outside of the membrane and crystallises in the hexagonal Ih form. Simultaneously, the membrane shrinks and dehydrate, leading to an increase of the hydronium ions concentration inside the matrix. Reversibly, the ice melts and the membrane re-hydrate upon heating. A model of solution, whose freezing point varies with the hydronium concentration, is proposed to calculate the quantity of ice formed as a function of temperature. The quantitative agreement between the model and experimental data explains the smooth and reversible behavior observed during the sorption or desorption of water, pointing out the origin of the phenomena. Other examples of water filled electrolyte nano-structures are eventually discussed, in the context of clarifying the conditions for water transport at low temperature.

Marie Plazanet; Renato Torre; Paolo Bartolini; Bruno Deme; Caterina Petrillo; Francesco Sacchetti

2013-05-02T23:59:59.000Z

438

Oxygen transfer in Bi{sub 2}O{sub 3}-based solid electrolytes  

Science Conference Proceedings (OSTI)

Materials with high oxygen conductivity are found in the system Bi{sub 2}O{sub 3}-Y{sub 2}O{sub 3}-ZrO{sub 2}. The values of conductivity are higher than those of the majority of bismuth oxide-based solid electrolytes that are thermo-dynamically stable at low temperatures. Doping of bismuth oxide-based solid electrolytes with calcium fluoride results in an increase of the rate of response of electrochemical oxygen sensors. No direct correlation between dynamic and electrochemical characteristics of the sensor has been observed. Utilization of intermediate layers made of materials with mixed oxygen and electronic conductivity between the electrode and the solid electrolyte does not lead to a substantial decrease in the polarization resistance, but increases the rate of response of potentiometric sensors. Electrochemical properties of several rare earth and strontium cobalties as electrodes for bismuth oxide-based solid electrolytes have been studied.

Kharton, V.V.; Naumovich, E.N. [Belarussian State Univ., Minsk (Belarus)

1993-12-01T23:59:59.000Z

439

Enabling multi-cation electrolyte usage in LMBs for lower cost and operating temperature  

E-Print Network (OSTI)

Alloy anodes form a promising path to the use of multi-cation electrolytes by increasing chemical stability. In this study, a lithium-magnesium alloy anode was developed such that lower cost and lower melting temperature ...

Blanchard, Allan (Allan B.)

2013-01-01T23:59:59.000Z

440

Anodic polymerization of vinyl ethylene carbonate in Li-Ion battery electrolyte  

E-Print Network (OSTI)

R.A. Sutula, F. McLamon, Battery Rsearch Pograms of theof Energy, in Selected Battery Topics. Proceedings of theEthylene Carbonate in Li-Ion Battery Electrolyte Guoying

Chen, Guoying; Zhuang, Guorong V.; Richardson, Thomas J.; Gao, Liu; Ross Jr., Philip N.

2005-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "aqueous electrolyte modeling" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Coordination Chemistry in magnesium battery electrolytes: how ligands affect their performance  

Science Conference Proceedings (OSTI)

Magnesium battery is potentially a safe, cost-effective, and high energy density technology for large scale energy storage. However, the development of magnesium battery has been hindered by the limited performance and the lack of fundamental understandings of electrolytes. Here, we present a coordination chemistry study of Mg(BH4)2 in ethereal solvents. The O donor denticity, i.e. ligand strength of the ethereal solvents which act as ligands to form solvated Mg complexes, plays a significant role in enhancing coulombic efficiency of the corresponding solvated Mg complex electrolytes. A new and safer electrolyte is developed based on Mg(BH4)2, diglyme and optimized LiBH4 additive. The new electrolyte demonstrates 100% coulombic efficiency, no dendrite formation, and stable cycling performance with the cathode capacity retention of ~90% for 300 cycles in a prototype magnesium battery.

Shao, Yuyan; Liu, Tianbiao L.; Li, Guosheng; Gu, Meng; Nie, Zimin; Engelhard, Mark H.; Xiao, Jie; Lu, Dongping; Wang, Chong M.; Zhang, Jiguang; Liu, Jun

2013-11-04T23:59:59.000Z

442

The design of a microfabricated air electrode for liquid electrolyte fuel cells  

E-Print Network (OSTI)

In this dissertation, the microfabricated electrode (MFE) concept was applied to the design of an air electrode for liquid electrolyte fuel cells. The catalyst layer of the electrode is envisioned to be fabricated by using ...

Pierre, Fritz, 1977-

2007-01-01T23:59:59.000Z

443

Market Potential of Electrolytic Hydrogen Production in Three Northeastern Utilities' Service Territories  

Science Conference Proceedings (OSTI)

Hydrogen produced by water electrolysis can be potentially cheaper than bottled industrial hydrogen. But in the Northeast, expensive electrolyzers, costly electricity, high interest rates, and excess hydrogen production capacity at existing plants make electrolytic hydrogen less attractive than bottled hydrogen.

1984-05-01T23:59:59.000Z

444

Novel hydrophobic ionic liquids electrolyte based on cyclic sulfonium used in dye-sensitized solar cells  

Science Conference Proceedings (OSTI)

A novel series of hydrophobic room temperature ionic liquids based on six cyclic sulfonium cations were first time synthesized and applied in dye-sensitized solar cells as pure solvents for electrolyte system. The chronoamperograms result showed that the length of substituent on sulfonium cations could inhibit the I{sub 3}{sup -} diffusion and the five-ring structure of sulfonium was benefit for fast triiodide ion diffusion. The electrochemical impendence spectra measurement of dye-sensitized solar cells with these ionic liquid electrolytes was carried out and the result indicated that the cations' structure had indeed influence on the cells' performance especially for the fill factor, which was further proved by the measurement result of I-V curves of these dye-sensitized solar cells. The conclusion was obtained that the electron exchange reaction on Pt counter electrode/electrolyte interface dominated the cells' performance for these ionic liquid electrolyte-based DSCs. (author)

Guo, Lei; Pan, Xu; Wang, Meng; Zhang, Changneng; Fang, Xiaqin; Chen, Shuanghong; Dai, Songyuan [Key Lab of Novel Thin Film Solar Cells, Institute of Plasma Physics, Chinese Academy of Sciences, P.O. Box 1126, Hefei, Anhui 230031 (China)

2011-01-15T23:59:59.000Z

445

Hydrogen production plants using electrolytic cells with low cost electrodes built into pressure tanks  

SciTech Connect

Electrolytic production method of generating hydrogen gas is briefly reviewed and critical components of electrolytic hydrogen production plants are listed. These components are then discussed and recommended approaches and arrangements cited. Recommended arrangement would be operated at moderate temperatures and gas pipe line pressures. A hypothetical 150 MW Hydrogen Plant is described, including estimates of cost and performance. Comments are made in regard to several possible generating systems which might be used to power hydrogen production plants. A comprehensive energy policy is appended.

Hall, F.F.

1978-02-01T23:59:59.000Z

446

Removal of uranium from aqueous HF solutions  

DOE Patents (OSTI)

This invention is a simple and effective method for removing uranium from aqueous HF solutions containing trace quantities of the same. The method comprises contacting the solution with particulate calcium fluoride to form uranium-bearing particulates, permitting the particulates to settle, and separting the solution from the settled particulates. The CaF.sub.2 is selected to have a nitrogen surface area in a selected range and is employed in an amount providing a calcium fluoride/uranium weight ratio in a selected range. As applied to dilute HF solutions containing 120 ppm uranium, the method removes at least 92% of the uranium, without introducing contaminants to the product solution.

Pulley, Howard (West Paducah, KY); Seltzer, Steven F. (Paducah, KY)

1980-01-01T23:59:59.000Z

447

NON-AQUEOUS DISSOLUTION OF MASSIVE PLUTONIUM  

DOE Patents (OSTI)

A method is presented for obtaining non-aqueous solutions or plutonium from massive forms of the metal. In the present invention massive plutonium is added to a salt melt consisting of 10 to 40 weight per cent of sodium chloride and the balance zinc chloride. The plutonium reacts at about 800 deg C with the zinc chloride to form a salt bath of plutonium trichloride, sodium chloride, and metallic zinc. The zinc is separated from the salt melt by forcing the molten mixture through a Pyrex filter.

Reavis, J.G.; Leary, J.A.; Walsh, K.A.

1959-05-12T23:59:59.000Z

448

Removal of uranium from aqueous HF solutions  

Science Conference Proceedings (OSTI)

This invention is a simple and effective method for removing uranium from aqueous HF solutions containing trace quantities of the same. The method comprises contacting the solution with particulate calcium fluoride to form uranium-bearing particulates, permitting the particulates to settle, and separating the solution from the settled particulates. The CaF2 is selected to have a nitrogen surface area in a selected range and is employed in an amount providing a calcium fluoride/uranium weight ratio in a selected range. As applied to dilute HF solutions containing 120 ppm uranium, the method removes at least 92% of the uranium without introducing contaminants to the product solution.

Pulley, H.; Seltzer, S.F.

1980-11-18T23:59:59.000Z

449

Novel Ternary Molten Salt Electrolytes for intermediate-temperature sodium/nickel chloride batteries  

SciTech Connect

The sodium-nickel chloride (ZEBRA) battery is typically operated at relatively high temperature (250~350°C) to achieve adequate electrochemical performance. Reducing the operating temperature in the range of 150 to 200°C can lead to enhanced cycle life by suppressing temperature related degradation mechanisms. The reduced temperature range also allows for lower cost materials of construction such as elastomeric sealants and gaskets. To achieve adequate electrochemical performance at lower operating temperatures requires an overall reduction in ohmic losses associated with temperature. This includes reducing the ohmic resistance of ?”-alumina solid electrolyte (BASE) and the incorporation of low melting point molten salt as the secondary electrolyte. In present work, planar-type Na/NiCl2 cells with a thin flat plate BASE (600 ?m) and low melting point secondary electrolyte were evaluated at reduced temperatures. Molten salt formulation for use as secondary electrolytes were fabricated by the partial replace of NaCl in the standard secondary electrolyte (NaAlCl4) with other lower melting point alkali metal salts such as NaBr, LiCl, and LiBr. Electrochemical characterization of the ternary molten salts demonstrated , improved ionic conductivity, and sufficient electrochemical window at reduced temperatures. Furthermore, Na/NiCl2 cells with 50 mol% NaBr-containing secondary electrolyte exhibited reduced polarizations at 175°C compared to the cell with the standard NaAlCl4 catholyte. The cells also exhibited stable cycling performance even at 150oC.

Li, Guosheng; Lu, Xiaochuan; Coyle, Christopher A.; Kim, Jin Yong; Lemmon, John P.; Sprenkle, Vincent L.; Yang, Zhenguo

2012-12-15T23:59:59.000Z

450

Hydrogen-fueled polymer electrolyte fuel cell systems for transportation.  

DOE Green Energy (OSTI)

The performance of a polymer electrolyte fuel cell (PEFC) system that is fueled directly by hydrogen has been evaluated for transportation vehicles. The performance was simulated using a systems analysis code and a vehicle analysis code. The results indicate that, at the design point for a 50-kW PEFC system, the system efficiency is above 50%. The efficiency improves at partial load and approaches 60% at 40% load, as the fuel cell operating point moves to lower current densities on the voltage-current characteristic curve. At much lower loads, the system efficiency drops because of the deterioration in the performance of the compressor, expander, and, eventually, the fuel cell. The results also indicate that the PEFC system can start rapidly from ambient temperatures. Depending on the specific weight of the fuel cell (1.6 kg/kW in this case), the system takes up to 180s to reach its design operating conditions. The PEFC system has been evaluated for three mid-size vehicles: the 1995 Chrysler Sedan, the near-term Ford AIV (Aluminum Intensive Vehicle) Sable, and the future P2000 vehicle. The results show that the PEFC system can meet the demands of the Federal Urban Driving Schedule and the Highway driving cycles, for both warm and cold start-up conditions. The results also indicate that the P2000 vehicle can meet the fuel economy goal of 80 miles per gallon of gasoline (equivalent).

Ahluwalia, R.; Doss, E.D.; Kumar, R.

1998-10-19T23:59:59.000Z

451

Sulfur gas sensor using a calcium fluoride solid electrolyte  

Science Conference Proceedings (OSTI)

The sulfur gas potentials in the H/sub 2/S + H/sub 2/ buffer gases were measured by a galvanic cell Ps/sub 2/(g),Au(Pt)/(MoS/sub 2/ + CaS)/CaF/sub 2//(Cu + Cu/sub 2/S + CaS)/Au(Pt) in the temperature range from 650/sup 0/ to 950/sup 0/C and Ps/sub 2/ region from 10/sup -2/ to 10/sup -10/ atm. A quick response time (within 5 to 10 min) in emf with the change of Ps/sub 2/ at a given temperature was observed by placing a MoS/sub 2/ and CaS mixed pellet auxiliary electrode at the bottom of the cylindrical single-crystal CaF/sub 2/ electrolyte. The observed emf's agreed well with with those calculated from the Nernst equation. Using this sensor, Ps/sub 2/ values in the SO/sub 2/ + H/sub 2/ + H/sub 2/S gas system were also evaluated from the measured emf at 827/sup 0/C and were found to be in close agreement with those calculated from the thermochemical tables.

Toniguchi, M.; Wakihara, M.; Uchida, T.; Hirakawa, K.; Nii, J.

1988-01-01T23:59:59.000Z

452

Polymer electrolyte fuel cells: Potential transportation and stationary applications  

DOE Green Energy (OSTI)

The application of the polymer electrolyte fuel cell (PEFC) as a primary power source in electric vehicles has received increasing attention during the last few years. This increased attention is the result of a combination of significant technical advances in this fuel cell technology and the initiation of some projects for the demonstration of a complete, PEFC-based power system a bus or in a passenger car. Such demonstration projects reflect an increase in industry`s faith in the potential of this technology for transportation applications, or, at least, in the need for a detailed evaluation of this potential. Nevertheless, large scale transportation applications of PEFCs require a continued concerted effort of research on catalysis, materials and components, combined with the engineering efforts addressing the complete power system. This is required to achieve a cost effective, highly performing PEFC stack and power system. A related set of technical and cost challenges arises in the context of potential applications of PEFCs for stationary power applications, although there are clearly some differences in their nature, particularly, to do with the different types of fuels to be employed for each of these applications. We describe in this contribution some recent results of work performed by the Core Research PEFC Program at Los Alamos National Laboratory, which has addressed materials, components and single cell testing of PEFCS. Also included are some recent observations and some insights regarding the potential of this fuel cell technology for stationary Power generation.

Gottesfeld, S.

1993-04-01T23:59:59.000Z

453

Separation of gases with solid electrolyte ionic conductors  

DOE Green Energy (OSTI)

The authors have developed a novel method of gas separation based on electrolyte ionic membrane technology. Separation of one gas from another occurs through an ion-conducting membrane by the passage of selected ions. Most systems studied have focused on oxygen ion conduction for the separation of oxygen from air, although protonic and halide-conducting solid materials also exist. As an example of this system, this paper concentrates on a study of a membrane reactor used in the production of syngas (CO + H{sub 2}) from methane. The membrane material is a modified perovskite-type oxide exhibiting mixed (electronic/ionic) conductivity. Mixed-conductivity oxides are promising materials for oxygen-permeating membranes that can operate without electrodes or external electrical circuitry. Extruded tubes of this material have been evaluated in a reactor operating at {approx} 850 C for partial oxidation of methane into syngas in the presence of a reforming catalyst. Separated oxygen on one side of the reactor wall was obtained from air on the other side. Methane conversion efficiencies of > 99% were observed, and some of the reactor tubes have been operated for > 1,000 h. Membrane tubes were fabricated from calcined powders by a plastic extrusion technique. Characterization of the mechanical, physical, and chemical properties of this material confirmed the stability exhibited in the reactor.

Balachandran, U.; Dusek, J.T.; Maiya, P.S.; Mieville, R.L.; Ma, B. [Argonne National Lab., IL (United States); Kleefisch, M.S.; Udovich, C.A. [Amoco Exploration and Production, Naperville, IL (United States)

1996-11-01T23:59:59.000Z

454

Polymer electrolyte fuel cells: Potential transportation and stationary applications  

DOE Green Energy (OSTI)

The application of the polymer electrolyte fuel cell (PEFC) as a primary power source in electric vehicles has received increasing attention during the last few years. This increased attention is the result of a combination of significant technical advances in this fuel cell technology and the initiation of some projects for the demonstration of a complete, PEFC-based power system a bus or in a passenger car. Such demonstration projects reflect an increase in industry's faith in the potential of this technology for transportation applications, or, at least, in the need for a detailed evaluation of this potential. Nevertheless, large scale transportation applications of PEFCs require a continued concerted effort of research on catalysis, materials and components, combined with the engineering efforts addressing the complete power system. This is required to achieve a cost effective, highly performing PEFC stack and power system. A related set of technical and cost challenges arises in the context of potential applications of PEFCs for stationary power applications, although there are clearly some differences in their nature, particularly, to do with the different types of fuels to be employed for each of these applications. We describe in this contribution some recent results of work performed by the Core Research PEFC Program at Los Alamos National Laboratory, which has addressed materials, components and single cell testing of PEFCS. Also included are some recent observations and some insights regarding the potential of this fuel cell technology for stationary Power generation.

Gottesfeld, S.

1993-01-01T23:59:59.000Z

455

Functionalized Polymers For Binding To Solutes In Aqueous Solutions  

NLE Websites -- All DOE Office Websites (Extended Search)

Functionalized Polymers For Binding To Solutes In Aqueous Solutions Functionalized Polymers For Binding To Solutes In Aqueous Solutions Functionalized Polymers For Binding To Solutes In Aqueous Solutions A functionalized polymer for binding a dissolved molecule in an aqueous solution is presented. Available for thumbnail of Feynman Center (505) 665-9090 Email Functionalized Polymers For Binding To Solutes In Aqueous Solutions A functionalized polymer for binding a dissolved molecule in an aqueous solution is presented. The polymer has a backbone polymer to which one or more functional groups are covalently linked. The backbone polymer can be such polymers as polyethylenimine, polyvinylamine, polyallylamine, and polypropylamine. These polymers are generally water-soluble, but can be insoluble when cross-linked. The functional group can be for example diol

456

Critical review of the chemistry and thermodynamics of technetium and some of its inorganic compounds and aqueous species  

SciTech Connect

Chemical and thermodynamic data for Technetium (Tc) and some of its inorganic compounds and aqueous species are reviewed here. Major emphasis is given to systems with potential geochemical applications, especially the geochemistry of radioactive waste disposal. Compounds considered include oxides, hydroxides, hydrates oxides, halides, oxyhalides, double halides, and sulfides. The aqueous species considered include those in both noncomplexing media (pertechnetates, technetates, aquo-ions, and hydrolyzed cations) and complexing media (halides, sulfates, and phosphates). Thermodynamic values are recommended for specific compounds and aqueous ions when reliable experimental data are available. Where thermodynamic data are inadequate or unavailable, the chemistry is still discussed to provide information about what needs to be measured, and which chemistry needs to be clarified. A major application of these thermodynamic data will be for chemical equilibrium modeling and for construction of potential-pH diagrams for aqueous solutions. Unfortunately, the present lack of data precludes such calculations for complexing aqueous media. The situation is much better for noncomplexing aqueous media, but the chemistry and thermodynamics of cationic Tc(V) species and hydrolyzed Tc(III) species are poorly understood. 240 references, 6 tables.

Rard, J.A.

1983-09-15T23:59:59.000Z

457

Hydrothermal processing of Hanford tank wastes: Process modeling and control  

Science Conference Proceedings (OSTI)

In the Los Alamos National Laboratory (LANL) hydrothermal process, waste streams are first pressurized and heated as they pass through a continuous flow tubular reactor vessel. The waste is maintained at reaction temperature of 300--550 C where organic destruction and sludge reformation occur. This report documents LANL activities in process modeling and control undertaken in FY94 to support hydrothermal process development. Key issues discussed include non-ideal flow patterns (e.g. axial dispersion) and their effect on reactor performance, the use and interpretation of inert tracer experiments, and the use of computational fluid mechanics to evaluate novel hydrothermal reactor designs. In addition, the effects of axial dispersion (and simplifications to rate expressions) on the estimated kinetic parameters are explored by non-linear regression to experimental data. Safety-related calculations are reported which estimate the explosion limits of effluent gases and the fate of hydrogen as it passes through the reactor. Development and numerical solution of a generalized one-dimensional mathematical model is also summarized. The difficulties encountered in using commercially available software to correlate the behavior of high temperature, high pressure aqueous electrolyte mixtures are summarized. Finally, details of the control system and experiments conducted to empirically determine the system response are reported.

Currier, R.P. [comp.

1994-10-01T23:59:59.000Z

458

Method and apparatus for destroying organic contaminants in aqueous liquids  

DOE Patents (OSTI)

A method and apparatus for destroying organic contaminants, such as trichloroethylene, in aqueous liquids, such as groundwater, utilizing steam stripping integrated with biodegradation. The contaminated aqueous liquid is fed into a steam stripper causing the volatilization of essentially all of the organic contaminants and a portion of the aqueous liquid. The majority of the aqueous liquid is discharged from the steam stripper. The volatilized vapors are then condensed to the liquid phase and introduced into a bioreactor. The bioreactor contains methanotrophic microorganisms which convert the organic contaminants into mainly carbon dioxide. The effluent from the bioreactor is then recycled back to the steam stripper for further processing.

Donaldson, Terrence L. (Lenior City, TN); Wilson, James H. (Oak Ridge, TN)

1993-01-01T23:59:59.000Z

459

Method and apparatus for destroying organic contaminants in aqueous liquids  

DOE Patents (OSTI)

A method and apparatus for destroying organic contaminants, such as trichloroethylene, in aqueous liquids, such as groundwater, utilizing steam stripping integrated with biodegradation. The contaminated aqueous liquid is fed into a steam stripper causing the volatilization of essentially all of the organic contaminants and a portion of the aqueous liquid. The majority of the aqueous liquid is discharged from the steam stripper. The volatilized vapors are then condensed to the liquid phase and introduced into a bioreactor. The bioreactor contains methanotrophic microorganisms which convert the organic contaminants into mainly carbon dioxide. The effluent from the bioreactor is then recycled back to the steam stripper for further processing. 2 figures.

Donaldson, T.L.; Wilson, J.H.

1993-09-21T23:59:59.000Z

460

ESS 2012 Peer Review - New Generation Aqueous Base Redox Flow...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

New Generation Aqueous Base Redox Flow Battery Component Development Wei Wang, Qingtao Luo, Xiaoliang Wei, Bin Li, Zimin Nie, Baowei Chen, Yuyan Shao, Vijayakumar Murugesan, Amy...

Note: This page contains sample records for the topic "aqueous electrolyte modeling" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

Corrosion problems with aqueous coolants, final report  

DOE Green Energy (OSTI)

The results of a one year program to characterize corrosion of solar collector alloys in aqueous heat-transfer media are summarized. The program involved a literature review and a laboratory investigation of corrosion in uninhibited solutions. It consisted of three separate tasks, as follows: review of the state-of-the-art of solar collector corrosion processes; study of corrosion in multimetallic systems; and determination of interaction between different waters and chemical antifreeze additives. Task 1 involved a comprehensive review of published literature concerning corrosion under solar collector operating conditions. The reivew also incorporated data from related technologies, specifically, from research performed on automotive cooling systems, cooling towers, and heat exchangers. Task 2 consisted of determining the corrosion behavior of candidate alloys of construction for solar collectors in different types of aqueous coolants containing various concentrations of corrosive ionic species. Task 3 involved measuring the degradation rates of glycol-based heat-transfer media, and also evaluating the effects of degradation on the corrosion behavior of metallic collector materials.

Diegle, R B; Beavers, J A; Clifford, J E

1980-04-11T23:59:59.000Z

462

CRACK GROWTH ANALYSIS OF SOLID OXIDE FUEL CELL ELECTROLYTES  

DOE Green Energy (OSTI)

Defects and Flaws control the structural and functional property of ceramics. In determining the reliability and lifetime of ceramics structures it is very important to quantify the crack growth behavior of the ceramics. In addition, because of the high variability of the strength and the relatively low toughness of ceramics, a statistical design approach is necessary. The statistical nature of the strength of ceramics is currently well recognized, and is usually accounted for by utilizing Weibull or similar statistical distributions. Design tools such as CARES using a combination of strength measurements, stress analysis, and statistics are available and reasonably well developed. These design codes also incorporate material data such as elastic constants as well as flaw distributions and time-dependent properties. The fast fracture reliability for ceramics is often different from their time-dependent reliability. Further confounding the design complexity, the time-dependent reliability varies with the environment/temperature/stress combination. Therefore, it becomes important to be able to accurately determine the behavior of ceramics under simulated application conditions to provide a better prediction of the lifetime and reliability for a given component. In the present study, Yttria stabilized Zirconia (YSZ) of 9.6 mol% Yttria composition was procured in the form of tubes of length 100 mm. The composition is of interest as tubular electrolytes for Solid Oxide Fuel Cells. Rings cut from the tubes were characterized for microstructure, phase stability, mechanical strength (Weibull modulus) and fracture mechanisms. The strength at operating condition of SOFCs (1000 C) decreased to 95 MPa as compared to room temperature strength of 230 MPa. However, the Weibull modulus remains relatively unchanged. Slow crack growth (SCG) parameter, n = 17 evaluated at room temperature in air was representative of well studied brittle materials. Based on the results, further work was planned to evaluate the strength degradation, modulus and failure in more representative environment of the SOFCs.

S. Bandopadhyay; N. Nagabhushana

2003-10-01T23:59:59.000Z

463

Sulfone-based electrolytes for high voltage li-ion batteries.  

Science Conference Proceedings (OSTI)

Sulfone-based electrolytes have been investigated as electrolytes for lithium-ion cells using high-voltage positive electrodes, such as LiMn{sub 2}O{sub 4} and LiNi{sub 0.5}Mn{sub 1.5}O{sub 4} spinels, and Li{sub 4}Ti{sub 5}O{sub 12} spinel as negative electrode. In the presence of imide salt (LiTFSI) and ethyl methyl sulfone or tetramethyl sulfone (TMS) electrolytes, the Li{sub 4}Ti{sub 5}O{sub 12}/LiMn{sub 2}O{sub 4} cell exhibited a specific capacity of 80 mAh g{sup -1} with an excellent capacity retention after 100 cycles. In a cell with high-voltage LiNi{sub 0.5}Mn{sub 1.5}O{sub 4} positive electrode and 1 M LiPF{sub 6} in TMS as electrolyte, the capacity reached 110 mAh g{sup -1} at the C/12 rate. When TMS was blended with ethyl methyl carbonate, the Li{sub 4}Ti{sub 5}O{sub 12}/LiNi{sub 0.5}Mn{sub 1.5}O{sub 4} cell delivered an initial capacity of 80 mAh g{sup -1} and cycled fairly well for 1000 cycles under 2C rate. The exceptional electrochemical stability of the sulfone electrolytes and their compatibility with the Li{sub 4}Ti{sub 5}O{sub 12} safer and stable anode were the main reason behind the outstanding electrochemical performance observed with high-potential spinel cathode materials. These electrolytes could be promising alternative electrolytes for high-energy density battery applications such as plug-in hybrid and electric vehicles that require a long cycle life.

Abouimrane, A.; Belharouak, I.; Amine, K. (Chemical Sciences and Engineering Division)

2009-05-01T23:59:59.000Z