Studies on anion promoted Titania 2: Preparation, characterisation and catalytic activity towards aromatic alkylation over sulfated titania

Abstract

Sulfated titania samples with varying amounts of sulfate have been prepared by solid–solid kneading, as well as aqueous impregnation method, and are characterized using X-ray diffraction XRD., FT-IR and N2 adsorption–desorption isotherm. Surface area, average pore diameter and total pore volume are found to increase with the increase in sulfate content up to 7.5 wt.%, and thereafter decreases. Alkylation of aromatic compounds benzene, toluene and chlorobenzene. with isopropanol is carried out in a fixed-bed flow reactor over these catalysts as a function of benzene to isopropanol molar ratio, reaction temperature, wt.% and source of sulfate ion. Among all the catalysts, the sample with 7.5 wt.% sulfate loading prepared from H2SO4 impregnation exhibits highest selectivity and yield towards alkylation of aromatic compounds to their corresponding isopropylated products.