Thermodynamics of Hydrogen Production from Dimethyl Ether Steam Reforming and Hydrolysis
Abstract
The thermodynamic analyses of producing a hydrogen-rich fuel-cell feed from the process of dimethyl ether (DME) steam reforming were investigated as a function of steam-to-carbon ratio (0-4), temperature (100 C-600 C), pressure (1-5 atm), and product species: acetylene, ethanol, methanol, ethylene, methyl-ethyl ether, formaldehyde, formic acid, acetone, n-propanol, ethane and isopropyl alcohol. Results of the thermodynamic processing of dimethyl ether with steam indicate the complete conversion of dimethyl ether to hydrogen, carbon monoxide and carbon dioxide for temperatures greater than 200 C and steam-to-carbon ratios greater than 1.25 at atmospheric pressure (P = 1 atm). Increasing the operating pressure was observed to shift the equilibrium toward the reactants; increasing the pressure from 1 atm to 5 atm decreased the conversion of dimethyl ether from 99.5% to 76.2%. The order of thermodynamically stable products in decreasing mole fraction was methane, ethane, isopropyl alcohol, acetone, n-propanol, ethylene, ethanol, methyl-ethyl ether and methanol--formaldehyde, formic acid, and acetylene were not observed. The optimal processing conditions for dimethyl ether steam reforming occurred at a steam-to-carbon ratio of 1.5, a pressure of 1 atm, and a temperature of 200 C. Modeling the thermodynamics of dimethyl ether hydrolysis (with methanol as the only product considered), the equilibriummore »
- Authors:
- Publication Date:
- Research Org.:
- Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
- Sponsoring Org.:
- US Department of Energy (US)
- OSTI Identifier:
- 836682
- Report Number(s):
- LA-14166
TRN: US200504%%68
- DOE Contract Number:
- W-7405-ENG-36
- Resource Type:
- Technical Report
- Resource Relation:
- Other Information: PBD: 1 Oct 2004
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 08 HYDROGEN; 30 DIRECT ENERGY CONVERSION; ACETONE; ACETYLENE; ATMOSPHERIC PRESSURE; CARBON DIOXIDE; CARBON MONOXIDE; ETHANE; ETHANOL; ETHYL ETHER; FORMIC ACID; FUEL CELLS; HYDROGEN; HYDROGEN PRODUCTION; HYDROLYSIS; METHYL ETHER; STEAM; THERMODYNAMICS; 33 ADVANCED PROPULSION SYSTEMS
Citation Formats
Semelsberger, T A. Thermodynamics of Hydrogen Production from Dimethyl Ether Steam Reforming and Hydrolysis. United States: N. p., 2004.
Web. doi:10.2172/836682.
Semelsberger, T A. Thermodynamics of Hydrogen Production from Dimethyl Ether Steam Reforming and Hydrolysis. United States. https://doi.org/10.2172/836682
Semelsberger, T A. 2004.
"Thermodynamics of Hydrogen Production from Dimethyl Ether Steam Reforming and Hydrolysis". United States. https://doi.org/10.2172/836682. https://www.osti.gov/servlets/purl/836682.
@article{osti_836682,
title = {Thermodynamics of Hydrogen Production from Dimethyl Ether Steam Reforming and Hydrolysis},
author = {Semelsberger, T A},
abstractNote = {The thermodynamic analyses of producing a hydrogen-rich fuel-cell feed from the process of dimethyl ether (DME) steam reforming were investigated as a function of steam-to-carbon ratio (0-4), temperature (100 C-600 C), pressure (1-5 atm), and product species: acetylene, ethanol, methanol, ethylene, methyl-ethyl ether, formaldehyde, formic acid, acetone, n-propanol, ethane and isopropyl alcohol. Results of the thermodynamic processing of dimethyl ether with steam indicate the complete conversion of dimethyl ether to hydrogen, carbon monoxide and carbon dioxide for temperatures greater than 200 C and steam-to-carbon ratios greater than 1.25 at atmospheric pressure (P = 1 atm). Increasing the operating pressure was observed to shift the equilibrium toward the reactants; increasing the pressure from 1 atm to 5 atm decreased the conversion of dimethyl ether from 99.5% to 76.2%. The order of thermodynamically stable products in decreasing mole fraction was methane, ethane, isopropyl alcohol, acetone, n-propanol, ethylene, ethanol, methyl-ethyl ether and methanol--formaldehyde, formic acid, and acetylene were not observed. The optimal processing conditions for dimethyl ether steam reforming occurred at a steam-to-carbon ratio of 1.5, a pressure of 1 atm, and a temperature of 200 C. Modeling the thermodynamics of dimethyl ether hydrolysis (with methanol as the only product considered), the equilibrium conversion of dimethyl ether is limited. The equilibrium conversion was observed to increase with temperature and steam-to-carbon ratio, resulting in a maximum dimethyl ether conversion of approximately 68% at a steam-to-carbon ratio of 4.5 and a processing temperature of 600 C. Thermodynamically, dimethyl ether processed with steam can produce hydrogen-rich fuel-cell feeds--with hydrogen concentrations exceeding 70%. This substantiates dimethyl ether as a viable source of hydrogen for PEM fuel cells.},
doi = {10.2172/836682},
url = {https://www.osti.gov/biblio/836682},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Fri Oct 01 00:00:00 EDT 2004},
month = {Fri Oct 01 00:00:00 EDT 2004}
}