Magnetic resonance imaging studies of catalytic monoliths

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This project aims to advance clean air technology for combustion gas management of exhaust from current engines fuelled by gasoline and diesel, but also for new and future generation technology. Vehicle emissions legislation is tightening around the world, including the recently published EUVII standards, and there is a continuing focus on the health consequences of particulate emissions from internal combustion engines (ICE). To meet legislation over the whole range of driving conditions, exhaust filters for current diesel and gasoline exhaust applications may face the challenging requirement of greater than 99.9% filtration efficiency without negatively affecting catalytic performance and fuel efficiency. This stringent filtration target can only be met by gaining a deep understanding of fluid flows in the porous filter medium, both of catalytic coating liquids during manufacturing, and of exhaust gases during operation. The generated know how will be applicable to alternative fuels including systems causing particulate matter from synthetic fuels, to capture unburned NH3 in NH3-ICE or urea particulates from selective catalytic reduction (SCR) on H2-ICE. This project will utilize state of the art magnetic resonance technology, such as rheo-NMR techniques to study the flow of catalytic washcoat slurry into the porous walls of the ceramic material, as arises during fabrication of the monolith, to understand deposition patterns and resultant pore structure. It will also use hyperpolarised xenon MRI, an emerging technology at the forefront of airway imaging in medicine, to study the gas flow patterns in finished monoliths to understand the impact of mass transport heterogeneity on the efficiency of filtration and the activity of the catalyst.