"Silica-supported heteropolyacids as catalysts in alcohol dehydration reactions"

P. VÁZQUEZ; L. PIZZIO; C. CÁCERES; M. BLANCO; H. THOMAS; E. ALESSO; L. FINKIELSZTEIN; B. LANTAÑO; G. MOLTRASIO; J. AGUIRRE

Journal of Molecular Catalysis A: Chemical

Elsevier

Lugar: Amsterdam; Año: 2000 vol. 161 p. 223 - 232

Catalysts based on Keggin-type heteropolyacids supported on silica were prepared for their use in dehydration of alcoholsin liquid phase. Species present in the catalysts were characterized by diverse physicochemical techniques, disclosing thatboth molybdophosphoric and tungstophosphoric acids are found with their primary Keggin structure intact. Their catalyticbehavior was studied in the dehydration of alcohol of interest for the production of intermediary compounds for fine . chemical industries. Specifically, the dehydration of 1,2-diphenylethanol, 1- 3,4-dimethoxyphenyl -2-phenylethanol andcholesterol was studied. It was obtained a process for the direct dehydration of cholesterol. It was found that the catalysts arevery active and selective, also allowing an easy separation from the reaction medium. The same catalysts were used severaltimes without appreciable loss of catalytic activity and after the reaction they showed physicochemical properties similar tothose of the original catalysts. q2000 Elsevier Science B.V. All rights reserved.