The coupling of reaction and diffusion between neighboring active sites in the catalyst pore leads to the spatiotemporal fluctuation in component concentration,which is very important to catalyst performance and hence its optimal design.Molecular dynamics simulation with hard-sphere and pseudo-particle modeling has previously revealed the non-stochastic concentration fluctuation of the reactant/product near isolated active site due to such coupling,using a simple model reaction of A → B in 2D pores.The topic is further developed in this work by studying the concentration fluctuation due to such coupling between neighboring active sites in 3D pores.Two 3D pore models containing an isolated active site and two adjacent active sites were constructed,respectively.For the isolated site,the concentration fluc-tuation intensifies for larger pores,but the product yield decreases,and for a given pore size,the product yield reaches a peak at a certain reactant concentration.For two neighboring sites,their distance(d)is found to have little effect on the reaction,but significant to the diffusion.For the same reaction compet-ing at both sites,larger d leads to more efficient diffusion and better overall performance.However,for sequential reactions at the two sites,higher overall performance presents at a smaller d.The results should be helpful to the catalyst design and reaction control in the relevant processes.

Haolei Zhang;Mingcan Zhao;Yanping Li;Chengxiang Li;Wei Ge

State Key Laboratory of Multiphase Complex Systems,Institute of Process Engineering,Chinese Academy of Sciences,Beijing 100190,China;School of Chemical Engineering,University of the Chinese Academy of Sciences.Beijing 100049,China;Dalian National Laboratory for Clean Energy,Chinese Academy of Sciences,Dalian,Liaoning 116023,China;Innovation Academy for Green Manufacture,Chinese Academy of Sciences,Beijing 100049,China

中国化学工程学报（英文版）

[1]Haolei Zhang;Mingcan Zhao;Yanping Li;Chengxiang Li;Wei Ge-.Concentration fluctuation caused by reaction-diffusion coupling near catalytic active sites)[J].中国化学工程学报（英文版）,2022(10):254-263

compet

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