Hybrid organic‐inorganic acid catalysts: The effect of active sites localization on catalytic characteristics in the processes of alcohols' etherification. A review

Abstract

AbstractThis article reviews the various types of hybrid organic–inorganic resin catalysts: mixed and co‐precipitated composites, loaded, and tailored systems. The review gives a generalization of the authors' results in the field of synthesis and research of organic–inorganic resin catalysts, in the context of the main trends in the development of this field of science. Based on a comparison of the productivity of organic–inorganic and commercial sulfonic resins, the role of acid sites localization for determining the catalytic characteristics of sulfonic resin catalysts in ethanol and isopropanol etherification with isobutylene is discussed. Studies showed that acid sites of loaded sulfonic resins, localized on the external surface, have the highest productivity. The effect of morphology on the differences in the activity of different types of sulfonic resins in the etherification reactions is more pronounced for materials with limited accessibility of acid sites due to internal diffusion. With an increase in the accessibility of acid sites, the polarity and molecule size of the reacting alcohols become the predominant factors. These findings have an impact on the design of organic–inorganic resin catalysts with high performance.