Synthesis and characterization of nano-crystalline sulfated zirconia by sol-gel method

Synthesis of nano-crystalline sulfated zirconia with crystallite size less than 20mn using the one-step as well as the two-step sol-gel technique was carried out. Tetragonal phase of sulfated zirconia was obtained on calcination at 600degreesC. All the sulfated zirconia samples were found to be active for benzylation of toluene showing 26-41% conversion of toluene, however, samples prepared by the one-step method showed higher conversion (33-41%) as compared to the samples prepared by the two-step method (26-28%). Furthermore, in the one-step method, the introduction of sulfuric acid prior to hydrolysis, results into improved structural and textural properties in terms of higher sulfur loading, smaller crystallite size, higher surface area, average pore diameter and higher catalytic conversion for benzylation of toluene. (C) 2004 Elsevier B.V. All rights reserved.