Magnetic resonance imaging studies of catalytic monoliths

该项目旨在推进清洁空气技术，用于当前汽油和柴油发动机废气的燃烧气体管理，以及新一代和未来一代技术。世界各地的车辆排放法规都在收紧，包括最近发布的EUVII标准，人们一直关注内燃机（ICE）颗粒物排放对健康的影响。为了满足整个驾驶条件范围内的法规要求，目前柴油和汽油排气应用的排气过滤器可能面临着在不影响催化性能和燃油效率的情况下，过滤效率超过99.9%的挑战。只有深入了解多孔过滤介质中的流体流动，包括制造过程中的催化涂层液体和运行过程中的废气，才能达到这一严格的过滤目标。所产生的知识将适用于替代燃料，包括从合成燃料中产生颗粒物质的系统，在NH3- ice中捕获未燃烧的NH3或在H2-ICE上选择性催化还原（SCR）中捕获尿素颗粒。该项目将利用最先进的磁共振技术，如流变核磁共振技术来研究陶瓷材料多孔壁中催化涂层浆液的流动，这是在整体制造过程中产生的，以了解沉积模式和最终的孔隙结构。它还将使用超极化氙核磁共振成像，这是一项处于医学气道成像前沿的新兴技术，研究成品单体中的气体流动模式，以了解质量传输异质性对过滤效率和催化剂活性的影响。

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.