Friedel-Crafts Alkylation of o-xylene over V2O5 / ZrO2 Catalysts

Abstract

The present study has undertaken the Friedel-Crafts benzylation of aromatics over the V₂O₅/ZrO₂ catalysts systems. Catalysts with different V₂O₅ content (0-15wt %) was prepared by wet impregnation method and characterized by XRD, BET surface area, FTIR and ^5’V NMR techniques. The surface acidic properties were determined by temperature programmed desorption of NH₃, cumene cracking and perylene adsorption. Under the optimized reaction conditions, these catalysts are found to be very effective and considerably more selective than the conventional homogeneous Lewis acid catalysts. The investigation of vanadia systems-catalyzed benzylation of o-xylene with benzyl chloride revealed that the catalytic activity and product selectivity are sensitive to the precise reaction parameters and can be related to the Lewis acidity of the systems. The reaction is found to be very clean and produces the desired monoalkylated product with high yield.