The group of Professor M-O. Coppens, Department of Chemical Engineering at University College London (UCL) is seeking a graduate student to work on Manipulation of Geometrical Effects at the Nanoscale to Control Catalysis, as part of research in the EPSRC-funded Centre for Nature-Inspired Engineering (CNIE). The PhD position advertised is supported by Synfuels China for four years. The PhD candidate will use specially designed equipment to obtain experimental insights on nano-confinement effects, including fractal surface roughness, on diffusion and reaction in porous catalysts. This information will be used in supported catalyst design.
More than 20 years ago, we used analytical calculations and computer simulations to suggest that fractal surface roughness has a significant effect on Knudsen diffusion, and hereby affects yields and product distributions of heterogeneously catalysed processes – the effects on processes like vinyl acetate production and catalytic reforming were shown to be significant. Despite this theoretical basis and circumstantial experimental evidence, there has never been any direct experimental demonstration, or use of this method as a practical design tool. This is because geometrical effects in real porous catalysts combine effects of pore network topology, pore shape, size distribution and surface geometry. Now, 20 years later, using rapid progress in 3D printing and synthesis capabilities, we are able to easily realise complex controlled geometrical environments, which can then be used to test diffusion and reaction, and optimise the geometry for desired outcomes. This will be the focus of the proposed project.
To support the investigations, a unique vacuum setup has been built in the CNIE that enables us to control pressure in two chambers independently, with a 3D printed channel of controlled, micro-structured geometry. By working under vacuum, diffusion is necessarily in the Knudsen regime and effects that would be present in nano-structured geometries at normal or high pressure can be tested using precisely manipulated, complex (including fractal) geometries at larger scale (sub-mm resolution), and directly compared to theoretical calculations. This project will involve a detailed series of experiments on classical and fractal geometries, first of pure self- and transport diffusion, then with reaction by embedding catalytic particles. These results can then be compared to nanostructured porous catalysts at regular pressures, and help in optimising the design of the catalyst surface – a unique capability for a range of catalytic processes.
Further information can be found at https://www.natureinspiredengineering.org.uk/news/two-phd-openings-on-nature-inspired-process-intensification
To apply visit https://atsv7.wcn.co.uk/search_engine/jobs.cgi?amNvZGU9MTgzNzc3OCZ2dF90ZW1wbGF0ZT05ODImb3duZXI9NTA0MTE3OCZvd25lcnR5cGU9ZmFpciZicmFuZF9pZD0wJnZhY3R5cGU9MTMwOCZwb3N0aW5nX2NvZGU9MjI0=&jcode=1837778&vt_template=982&owner=5041178&ownertype=fair&brand_id=0&vactype=1308&posting_code=224
Deadline: 16th February 2020