EAPSI:Purification of Hydrogen-Nitrogen Binary Gas Mixtures for Effective Use of Ammonia as a Hydrogen Storage Material

Lundin Sean-Thomas B, Golden CO

Investigators

Abstract

This award supports research that will contribute to the ongoing effort to develop alternative energy methods toward a renewable energy future. An ammonia synthesis and decomposition energy framework is one possibility for a carbon free fuel network in which all carbon-based greenhouse gases are eliminated from the process. The ideal future process would involve ammonia synthesis from water via electrolysis, transport to an end-user and then conversion into hydrogen to be used efficiently in fuel cells. Finding an efficient means of decomposing ammonia into hydrogen remains an underdeveloped region of this process and the proposed work will provide a much better understanding of using palladium membranes to this end. The research involves the purification of hydrogen from streams containing nitrogen using palladium membranes. Specifically, the inhibition of hydrogen transport by adsorbed nitrogen species, which correlates to a reduction in hydrogen productivity, will be investigated. The membranes will be fabricated at the Colorado School of Mines and then tested and characterized at the University of Tokyo under the advisement of Professor Shigeo Ted Oyama, who has knowledge and expertise using a specific analysis method known as the time-lag technique. A method of minimizing nitrogen adsorption on Palladium membranes to improve membrane performance through the use of either palladium-silver or palladium-gold alloys will be studied, based on results from a recent theoretical study by Chantaramolee et al. Testing of membranes will involve exposure to hydrogen, nitrogen, and argon gases with measurements of hydrogen permeance being used to characterize the flux inhibition caused by adsorbed nitrogen species. Characterization of the membranes will involve techniques such as FTIR, XPS, and the time-lag technique which Prof. Oyama's lab has used previously. Success will be determined by the ability to characterize the temperature and pressure dependence of the flux inhibition, as well as isolating which surface species (N, NH, NH2 and/or NH3) are most stable on the surface of the membranes. This NSF EAPSI award is funded in collaboration with the Japan Society for the Promotion of Science.