AUTOMOTIVE

The research, supported by the DOE's Office of Fossil Energy and reported in the current issue of the prestigious journal "Science" published by the American Association for the Advancement of Science, predicts hydrogen flux through metal alloy separation membranes that could be used to produce pure hydrogen. "This research demonstrates our vision of coupling computational and experimental methods to facilitate rapid research and development of advanced technologies," said Anthony Cugini, focus area leader of Computational and Basic Sciences at NETL. "In essence, we are developing the computational tools to prescreen hydrogen separation membranes." These membranes allow pure hydrogen to pass through, while blocking impurities that are present with other gases in the production of hydrogen from fossil energy resources. Separation is a critical component of hydrogen production. Impurities lessen the effective use of hydrogen. Membranes have the ability to remove virtually all of the impurities from the hydrogen stream. The use of advanced computing to determine the ability of candidate membranes to produce pure hydrogen would be a time- and money-saving step for hydrogen researchers. Instead of having to produce a large suite of alloys with various proportions of metals--such as palladium and copper--and then test them to determine optimum compositions for maximum hydrogen purification, they could predict in advance which compositions would have the desirable properties. The research team at NETL in collaboration with Carnegie Mellon is investigating a new hydrogen membrane material--a copper palladium alloy--that allows hydrogen to be processed without contamination by other gases such as hydrogen sulfide during the purification process. "We coupled computational modeling with experimental activity to develop a predictive model for hydrogen flux through copper palladium alloys," said David Sholl, associate professor in chemical engineering at Carnegie Mellon. "We now have a solid method in the screening of other complex alloys for the future production of hydrogen," he said. "Ultimately, we see our new computational tools helping to take us into the new hydrogen economy as we scramble to harness this clean fuel, increasingly driven by our long-term worries about oil supplies as well as environmental challenges," Sholl said. "Efficient techniques for large-scale purification of hydrogen are of world-wide interest as we work toward a hydrogen-based economy," said John Winslow, technology manager for Coal Fuels and Hydrogen at NETL. "If high flux membranes that resist chemical contamination can be developed, the impact of these devices on industrial hydrogen purification would be dramatic."