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Two dealuminated HY zeolites were employed as catalysts for the Friedel−Crafts reaction of biphenyl with benzyl chloride in a slurry batch reactor, with solvents cyclopentane, cyclohexane, and methylcyclohexane, at temperature from 50 to 100 °C. Mainly benzylbiphenyl isomers (M), but also appreciable quantities of dibenzyl derivatives (D) were obtained and determined. Within the monobenzylated fraction, a para-selectivity of 65−70% at 60% conversion was reached. Magnetic stirring was found to be adequate for a chemically controlled reaction kinetics. Kinetic models, including equations for the process itself and for the catalyst deactivation, and applied on the basis of optimization procedures, were used to correlate the results. The model of choice was able to interpret runs carried out at different doses of catalyst and different initial concentrations of the benzylating agent. A solvent effect on the kinetics was evidenced. Deactivated catalysts were regenerated for a few reaction−regeneration cycles.

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The liquid-phase alkylation of aromatics has been effected traditionally with catalysis by inorganic acids or AlCl 3 and similar compounds. However the increasing importance of solid acid catalysts is changing the procedures in this field. One of the prerequisites for the development of relevant processes, and the design of reactors, is knowledge of the kinetic data in reactions catalyzed by solid acids. This review examines the information available on the kinetics of alkylations catalyzed by solid acids, mainly zeolites, supported metal chlorides and oxides, mesoporous (MCM) materials, and heteropolyacids, but also other less studied materials.