Advanced Catalytic Systems for Environmental Applications

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Catalysis is ubiquitous in all aspects of daily life. Indeed, without catalysis, life on earth as we know it would not be possible, and the development of the catalyst that allowed the synthesis of ammonia is one of the great turning points in history. In recent times, we are plagued with many environmental problems, including global warming caused by greenhouse gas emissions. In a drive to reduce GHG from the transportation sector, there has been a lot of focus on using natural gas as a fuel, which is currently abundant and cheap, and has the added advantage of producing few particulates. It produces the least amount of GHG per energy unit produced, compared to other hydrocarbon fuels. however, the natural gas engine, like all others, does not burn 100% of the fuel, and therefore significant amounts of methane can be present in the exhaust stream. If these are emitted to the atmosphere, much of the GHG benefit of using methane as a fuel would be lost. Since 2016 methane has been a controlled emission, and the only way to destroy it is through the use of a catalytic converter. Unfortunately, methane is the most difficult hydrocarbon to combust catalytically, and normally requires a high temperature. The best catalysts available are based around platinum and palladium, but these suffer from severe deactivation effects in the presence of water. The catalyst required also has significantly different attributes depending on whether or not there is an excess of oxygen (lean burn) or it is present in stoichiometric amounts. There is a desperate need for an effective catalyst for the exhaust gas after treatment from natural gas fueled vehicles. We have recently demonstrated improved catalysts for the lean burn engine operation, which may lead to improved commercial catalysts. However, these formulations will not be appropriate for stoichiometric operation, which seems to be the major trend for the automobile industry at present. The main objective of this project is the development of a stable methane oxidation catalyst that will function effectively, and for a sufficient length of time, to meet the requirements of a stoichiometric natural gas fueled engine. The primary objective is to develop a catalyst that is superior to the best catalysts currently available, regardless of precious metals loading, and the secondary objective is to develop catalysts with reduced amounts of precious metals to reduce the overall cost.