Influence of temperature inhomogeneity on product profile of reactions occurring within zeolites

Journal of Chemical Sciences

S Yashonath1 2²  G Ananthakrishna2¹  A V Anil Kumar² 

[1] Centre for Condensed Matter Theory, Indian Institute of Science, Bangalore 560 012, India$$;Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560 012, India$$

关键词: Reaction;    zeolites;    diffusion;    temperature inhomogeneity.;   

DOI  :  

来源: Indian Academy of Sciences

【 摘 要 】

In zeolites, diffusion is often accompanied by a reaction or sorption which in turn can induce temperature inhomogeneities. Monte Carlo simulations of Lennard-Jones atoms in zeolite NaCaA are reported for the presence of a hot zone presumed to be created by a reaction or chemi- or physi-sorption site. These simulations show that the presence of localized hot regions can alter both kinetic and transport properties such as diffusion. Further, we show that enhancement of diffusion constant is greater for systems with larger barrier height, a surprising result that may be of considerable significance in many chemical and biological processes. We find an unanticipated coupling between reaction and diffusion due to the presence of a hot zone in addition to that which normally exists via concentration. Implications of this coupling for the product profile of a reaction are discussed. We also propose a mechanism by which mobility of ions or diffusion of molecular species within biomembranes may take place.

【 授权许可】

Unknown