Sulfur Tolerant Shift Catalysts for Fuel Cell Applications

摘要

There are numerous types of water gas shift catalysts commercially available, including low temperature Cu-based catalysts, high temperature Fe/Cr/Al catalysts, intermediate temperature non-pyrophoric precious metal catalysts, and Co/Mo-based sour gas shift catalysts. Of the available commercial catalysts, only sour gas shift catalysts can tolerate high levels of sulfur, but these catalysts typically require at least 300-500 ppm H2S and higher to remain as an active sulfide. Low temperature Cu-based catalysts deactivate in sub ppm levels of sulfur; while higher temperature precious metal and Fe-based catalysts are only stable at levels below about 50 ppm H2S.