Multicontaminant Warm Gas Cleanup

76212S Emission control technologies for IGCC (Integrated Gasification Combined Cycle) plants must address the removal of mercury, sulfur oxides, nitrogen oxides, and particulates. Two types of technologies are available for synthesis-gas clean-up from these plants: (1) hot gas cleanup (which operates at approximately 1,000¿F) and (2) cold gas cleanup (less than 100¿F). However, a warm gas cleanup technology that operates at 300 ¿ 700¿F could more easily be used in association with downstream power generation (gas and steam turbines) as well as in fuel and chemical synthesis (e.g. methanol and Fisher-Tropsch synthesis). This project will develop technology for the simultaneous removal of sulfur and mercury compounds from syngas in this mid-temperature range (300 ¿ 700¿F). Phase I identified a family of a catalysts that can be used to oxidize the hydrogen sulfide, found in synthesis gas produced by coal gasification, directly into elemental sulfur. These catalysts do not consume valuable hydrogen and can operate at warm gas temperatures of approximately 400 degrees Fahrenheit at gasifier pressures. In Phase II, the catalyst formulation will be further developed and optimized to improve its activity for hydrogen sulfide oxidation and reduce the amount of oxygen that must be added to the system. A bench scale demonstration of the process will be conducted, and an independent evaluation will be performed by an outside laboratory. This will be followed by a detailed economic analysis of the process. Commercial Applications and Other Benefits as described by the awardee: This technology should significantly improve the energy efficiency and process economics for producing electric power from coal gasification. With this technology, the synthesis gas would not have to be cooled in order to remove the contaminants, thus improving the thermal efficiency of the process.