Styrene from toluene by combinatorial catalysis

The side-chain alkylation of toluene with methanol is one alternative technology to produce styrene that has been given attention in the last few years. In the literature basic materials has been proposed as catalyst for the reaction but the real number of tested catalysts is very small and few preparation parameters have been taken into account. In this work a combinatorial approach has been used to explore the possibilities of basic zeolites to carry out such reaction. To do this, the following catalyst variables have been studied: nature of zeolite, framework composition, nature and content of compensating cation and method of incorporation (exchange, impregnation). The results obtained confirm the requirements of both basic and acid sites in the catalysts and show the compromise between these two functions. The study carried out shows that zeolite-based catalysts are still poor reactive to give the styrene/ethylbenzene yields required for converting this process in a real alternative to the existing one, based on the alkylation of benzene with ethylene, followed by the dehydrogenation of ethylbenzene to styrene.