A common way to design a chemical reactor is to determine the optimal steady-state operational window and to operate the reactor as close as possible to that steady-state configuration. Nevertheless, it has been shown that periodic operation, when one or several input parameters are periodically modulated, can result in much better process performance, especially for complex reactions with two or more parallel or consecutive pathways. The origin of improvement is related to the fact that for such systems, the periodic modulation will cause the conversion (and selectivity) to change periodically, as well, with the mean value which is different from their steady-state values. Nevertheless, the improvement is obtained only in some cases, while in some others the periodic operation can be unfavorable and performance can be deteriorated.
In this seminar, recent developments in our research group in the area of fast temperature modulation will be presented. In general, periodic operations are more complex and more costly to develop and only significant improvements of selectivity will justify their application. Generally applicable methods of identifying catalytic reactions that are enhanced by periodic operation will be highlighted. We have shown that there exists a family of hydrogenation reactions proceeding via a parallel-consecutive network where fast temperature modulation can be used for kinetic resolution to substantially increase the selectivity to the desired products. Fast temperature modulation requires to use special catalysts, having both catalytic and heating functions. In general, these catalysts are characterized by the presence of slow reactant diffusion in a mesoporous network and a spill-over effect over catalytic (surface) sites. Their heating is realized via doping with magnetic nanoparticles absorbing radiofrequency (RF) field in the kHz range. The cyclic kinetics of diffusion and surface reaction leads to different rates of reaction which follows the given modulation, so as to provide a unique response in selectivity pattern for each composition of reaction mixture on either shape or amplitude of modulation.
Evgeny Rebrov got his PhD in Chemistry from Boreskov Institute of Catalysis in 1999 and his DSc in Chemical Engineering from Lomonosov Moscow University of Fine Chemical Technology. After 4 years of post-doctoral research work with Prof Jaap Schouten, he became Assistant Professor at Eindhoven University of Technology. In 2007 he got a fellowship from the British Council-NWO partnership program in science and went to Cambridge University (UK). In 2009, he was appointed Visiting Research Professor at Wright State University (Dayton, Ohio) and became Chair of Process and Reactor Engineering at Queen’s University Belfast in 2010. In 2014, he took his present position at the University of Warwick. He is member of the Young Academy of Europe (YAE) and member of editorial board of Reactions and AIMS Materials Science journals and member of international scientific committees of three international conferences. Prof. Evgeny Rebrov has published more than 170 scientific papers in peer-reviewed journals and 9 book chapters (h-index =29). He is co-founder and CTO at StoliCatalysts Ltd.