Honda researchers reveal nano-scale platinum and rhodium and iron containing catalyst formulations for hydrogen generation in U.S. Patent Application 20100022386. The formulations meet the need for highly active and selective catalysts for the generation of hydrogen and the oxidation of carbon monoxide and to thereby provide a hydrogen-rich gas, such as a hydrocarbon-rich syngas, from a gas mixture of at least carbon monoxide and water.
The application discloses methods and catalysts to generate a hydrogen-rich gas from gas mixtures containing carbon monoxide and water, such as water-containing syngas mixtures.
More particularly, say inventors Alfred Hagemeyer, Christopher James Brooks, Raymond E. Carhart, Karin Yaccato, Cory Bernard Phillips, Peter Strasser and Robert K. Grasselli, the invention includes methods using both precious metal- and non-precious metal-containing catalysts. The catalysts may be supported on a variety of catalyst support materials. The catalysts exhibit both high activity and selectivity to hydrogen generation and carbon monoxide oxidation
The catalyst components are typically present in a mixture of the reduced or oxide forms; typically one of the forms will predominate in the mixture. Such a water-gas-shift (WGS) catalyst may be prepared by mixing the metals and/or metalloids in their elemental forms or as oxides or salts to form a catalyst precursor. This catalyst precursor mixture generally undergoes a calcination and/or reductive treatment, which may be in-situ (within the reactor), prior to use as a WGS catalyst.
Without being bound by theory, the catalytically active species are generally understood to be species which are in the reduced elemental state or in other possible higher oxidation states. The catalyst precursor species are believed to be substantially completely converted to the catalytically active species by the pre-use treatment. Nonetheless, the catalyst component species present after calcination and/or reduction may be a mixture of catalytically active species such as the reduced metal or other possible higher oxidation states and uncalcined or unreduced species depending on the efficiency of the calcination and/or reduction conditions.