Sulfated zirconia and its modified versions as promising catalysts for industrial processes

Zirconium oxide, or zirconia, when modified with anions such as sulfate ions forms a highly acidic or superacidic catalyst depending on the treatment conditions. This catalyst is found to be well suited for catalyzing reactions of industrial importance, e.g. hydrocarbon isomerization, methanol conversion to hydrocarbons, alkylation, acylation, esterification, etherification, condensation, nitration, cyclization, hydration-dehydration, carbonylation, oligomerization, Fischer-Tropsch reaction, cracking and hydrocracking reactions, methane oxidative coupling, thioacetalization, adamantylation, manufacture of hydrogen peroxide, etc. The surface properties of these catalysts can be further modified in conjunction with noble or transition metals as promoters as well as with carbon molecular sieves. This review highlights the chemistry and engineering aspects of sulfated zirconia catalyst and its modified forms. (C) 1999 Elsevier Science B.V. All rights reserved.