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Hydrothermal solution calorimetry in acidic aqueous solutions and revisiting the standard partial molal thermodynamic properties of Nd3+ from 25 to 300 °C

Journal Article · · Geochimica et Cosmochimica Acta
 [1];  [1]
  1. New Mexico Institute of Mining and Technology, Socorro, NM (United States)
The mobility of rare earth elements (REE) can be predicted in aqueous fluids using geochemical modeling but the accuracy of these models strongly depends on the availability of robust thermodynamic properties for the REE aqueous species. The REE3+ aqua ions are important in the derivation of the formation constants of all the major REE complexes including the chloride, sulfate, and fluoride species which predominate in many hydrothermal-magmatic systems. However, the thermodynamic properties of the REE3+ aqua ions are still commonly derived from the Helgeson-Kirkham-Flowers (HKF) equation of state parameters tabulated several decades ago. The standard state thermodynamic properties at reference conditions (25 °C and 1bar) and their extrapolations to high temperature need to be verified, if not revised, based on hydrothermal experiments. In this study, the enthalpy of solution was measured for synthetic Nd hydroxide from 25 to 150 ºC to retrieve the standard partial molal thermodynamic properties of Nd3+ as a function of temperature. The experiments were conducted in aqueous perchloric acid based solutions with starting pH of 2 and varying ionic strength (0.01 to 0.09 mol/kg NaClO4). The standard partial molal enthalpy of formation (ΔfH°) of Nd3+ derived from the experimental study displays differences of up to 10 kJ/mol compared to the enthalpy values derived from the HKF equation of state in the studied temperature range. These inaccuracies are resolved by adjusting the standard partial molal Gibbs energy of formation (ΔfG°) of Nd3+ at 25 °C and 1 bar from -672.0 to -679.7 kJ/mol. The heat capacity function (Cp°) derived between 25 and 150 ºC can be described by: Cp° = a0 + a1·T + a2·T-2, with a0 = 1256, a1 = -2.68, a2 = -55.56·106 and T in Kelvin. A set of recommended thermodynamic properties is provided for the Nd3+ aqua ions and corrections are provided for the chloride and fluoride species to remain internally consistent with the experimentally derived properties. These results allow predicting accurately the solubility of monazite between 25 and 300 ºC. Before these corrections, the properties for the Nd3+ aqua ions derived from the HKF parameters resulted in up to ~1.5 orders of magnitude lower monazite solubility than determined experimentally. Here, a revision of the REE+3 aqua ions properties is necessary to accurately predict the mobility of REE in hydrothermal acidic solutions.
Research Organization:
New Mexico Institute of Mining and Technology, Socorro, NM (United States)
Sponsoring Organization:
National Science Foundation (NSF); USDOE Office of Science (SC), Basic Energy Sciences (BES)
Grant/Contract Number:
SC0021106
OSTI ID:
2522073
Report Number(s):
DOE-NMT--0021106
Journal Information:
Geochimica et Cosmochimica Acta, Journal Name: Geochimica et Cosmochimica Acta Vol. 406; ISSN 0016-7037
Publisher:
Elsevier; The Geochemical Society; The Meteoritical SocietyCopyright Statement
Country of Publication:
United States
Language:
English

References (70)

PRSV: An improved peng-Robinson equation of state for pure compounds and mixtures journal April 1986
PRSV: The stryjek-vera modification of the peng-robinson equation of state. Parameters for other pure compounds of industrial interest journal February 1989
The standard molar enthalpies of formation of the rare earth trihalides IV. DyCl3(s) and NdCl3(s) journal December 1996
Hydrothermal transport and deposition of the rare earth elements by fluorine-bearing aqueous liquids journal August 2014
The Rare Earth Elements: Demand, Global Resources, and Challenges for Resourcing Future Generations journal April 2017
Calculation of the thermodynamic and transport properties of aqueous species at high pressures and temperatures: Correlation algorithms for ionic species and equation of state predictions to 5 kb and 1000°C journal August 1988
Calculation of the thermodynamic and transport properties of aqueous species at high pressures and temperatures: Standard partial molal properties of inorganic neutral species journal September 1989
The density model for estimation of thermodynamic parameters of reactions at high temperatures and pressures journal July 1991
Examination of comparative rare earth element complexation behavior using linear free-energy relationships journal March 1992
Rare earth elements in hydrothermal systems: Estimates of standard partial molal thermodynamic properties of aqueous complexes of the rare earth elements at high pressures and temperatures journal November 1995
Thermophysics of the lanthanide trihydroxides II. Heat capacities from 10 to 350 K of Nd(OH)3 and Tb(OH)3. Lattice and Schottky contributions journal April 1980
Standard molar enthalpy of formation of neodymium hydroxide journal October 1989
SUPCRT92: A software package for calculating the standard molal thermodynamic properties of minerals, gases, aqueous species, and reactions from 1 to 5000 bar and 0 to 1000°C journal August 1992
Standard thermodynamic properties and heat capacity equations of rare earth hydroxides: journal October 1998
Fractionation of the REE during hydrothermal processes: constraints from the Bayan Obo Fe-REE-Nb deposit, Inner Mongolia, China. journal September 2000
Inorganic species in geologic fluids: Correlations among standard molal thermodynamic properties of aqueous ions and hydroxide complexes journal March 1997
Prediction of the thermodynamic properties of aqueous metal complexes to 1000°C and 5 kb journal April 1997
The volumetric and thermochemical properties of , , , and at K and MPa journal May 2003
Thermochemistry of lanthanum, neodymium, samarium and americium trihydroxides and their relation to the corresponding hydroxycarbonates journal August 1997
The enthalpies of formation of lanthanide compounds journal July 2001
The enthalpies of formation of lanthanide compounds I. LnCl3(cr), LnBr3(cr) and LnI3(cr) journal July 2001
The enthalpies of formation of lanthanide compounds journal July 2001
The aqueous geochemistry of the rare earth elements. Part XIV. The solubility of rare earth element phosphates from 23 to 150 °C journal April 2005
The solubility of xenotime-(Y) and other HREE phosphates (DyPO 4 , ErPO 4 and YbPO 4 ) in aqueous solutions from 100 to 250 °C and p sat journal April 2015
Hydrothermal transport, deposition, and fractionation of the REE: Experimental data and thermodynamic calculations journal November 2016
Hydrothermal solubility of TbPO4, HoPO4, TmPO4, and LuPO4 xenotime endmembers at pH of 2 and temperatures between 100 and 250 °C journal April 2021
The genesis of the Ashram REE deposit, Quebec: Insights from bulk-rock geochemistry, apatite-monazite-bastnäsite replacement reactions and mineral chemistry journal September 2021
The solubility and speciation of Nd in carbonate-bearing hydrothermal fluids up to 250 °C journal November 2022
Optimized thermodynamic properties of REE aqueous species (REE3+ and REEOH2+) and experimental database for modeling the solubility of REE phosphate minerals (monazite, xenotime, and rhabdophane) from 25 to 300 °C journal January 2024
Experimental determination of synthetic NdPO4 monazite end-member solubility in water from 21°C to 300°C: implications for rare earth element mobility in crustal fluids journal May 2004
An experimental study of the solubility and speciation of neodymium (III) fluoride in F-bearing aqueous solutions journal June 2007
An experimental study of the solubility and speciation of the Rare Earth Elements (III) in fluoride- and chloride-bearing aqueous solutions at temperatures up to 300°C journal December 2009
Hydrothermal mobilization of pegmatite-hosted REE and Zr at Strange Lake, Canada: A reaction path model journal December 2013
Internally consistent thermodynamic data for aqueous species in the system Na–K–Al–Si–O–H–Cl journal August 2016
The solubility of monazite (CePO4), SmPO4, and GdPO4 in aqueous solutions from 100 to 250 °C journal December 2018
The solubility of monazite (LaPO4, PrPO4, NdPO4, and EuPO4) endmembers in aqueous solutions from 100 to 250 °C journal July 2020
From mantle to critical zone: A review of large and giant sized deposits of the rare earth elements journal May 2016
The heat capacity of NdPO4 journal November 2006
Standard partial molar heat capacities and enthalpies of formation of aqueous aluminate under hydrothermal conditions from integral heat of solution measurements journal November 2014
Thermodynamics of solid phases containing rare earth oxides journal September 2015
The story of rare earth elements (REEs): Occurrences, global distribution, genesis, geology, mineralogy and global production journal July 2020
Thermochemical properties of yttrium, lanthanum, and the lanthanide elements and ions journal December 1976
Enthalpy of Solution of CO2 in Aqueous Solutions of Primary Alkanolamines: A Comparative Study of Hindered and Nonhindered Amine-Based Solvents journal June 2014
The Heat of Formation of Lanthanum Oxide 1 journal July 1965
Thermochemistry of the Rare Earths. I. Cerium and Neodymium journal August 1952
The Heat of Combustion of Neodymium 1 journal November 1952
AN EQUATION FOR THE REPRESENTATION OF HIGH-TEMPERATURE HEAT CONTENT DATA 1 journal August 1932
Apparent and partial molal heat capacities of aqueous rare earth nitrate solutions at 25.degree.C journal October 1979
Standard State Thermodynamic Properties of Aqueous Sodium Chloride Using High Dilution Calorimetry at Extreme Temperatures and Pressures journal March 2009
Carbonate complexation enhances hydrothermal transport of rare earth elements in alkaline fluids journal March 2022
SciPy 1.0: fundamental algorithms for scientific computing in Python journal February 2020
Raman spectroscopic study of anhydrous and hydrous REE phosphates, oxides, and hydroxides journal January 2024
Calculation of the thermodynamic properties of aqueous species at high pressures and temperatures. Effective electrostatic radii, dissociation constants and standard partial molal properties to 1000 °C and 5 kbar journal January 1992
The Thermodynamic Properties of the f -Elements and their Compounds. Part 2. The Lanthanide and Actinide Oxides journal March 2014
Thermophysical Properties of Fluid H 2 O journal January 1984
Maud: a Rietveld analysis program designed for the internet and experiment integration journal August 2000
New developments in the Inorganic Crystal Structure Database (ICSD): accessibility in support of materials research and design journal May 2002
Concerning the so-called Y(OH)3-type structure and the structure of La(OH)3 journal April 1953
Refinement of neodymium trihydroxide journal July 1976
Standard Thermodynamic Properties and Heat Capacity Equations for Rare Earth Element Hydroxides journal June 1998
Thermochemistry of rare-earth orthophosphates journal September 2001
Lithogeochemical Vectors for Hydrothermal Processes in the Strange Lake Peralkaline Granitic REE-Zr-Nb Deposit journal May 2016
Mineralogy, Chemistry, and Fluid-Aided Evolution of the Pea Ridge Fe Oxide-(Y + REE) Deposit, Southeast Missouri, USA journal November 2016
The Genesis of Hydrothermal Fluorite-REE Deposits in the Gallinas Mountains, New Mexico journal March 2000
Hydrothermal Mobilisation of the Rare Earth Elements - a Tale of "Ceria" and "Yttria" journal October 2012
Theoretical prediction of the thermodynamic behavior of aqueous electrolytes by high pressures and temperatures; IV, Calculation of activity coefficients, osmotic coefficients, and apparent molal and standard and relative partial molal properties to 600 degrees C and 5kb journal December 1981
The thermodynamics of cation hydrolysis journal September 1981
Calculation of the thermodynamic and transport properties of aqueous species at high pressures and temperatures; revised equations of state for the standard partial molal properties of ions and electrolytes journal January 1988
GEM-SELEKTOR GEOCHEMICAL MODELING PACKAGE: TSolMod LIBRARY AND DATA INTERFACE FOR MULTICOMPONENT PHASE MODELS journal October 2012
MINES thermodynamic database dataset September 2023