Heteropolyacid supported on acidic clay: A novel efficient catalyst for alkylation of ethylbenzene with dilute ethanol to diethylbenzene in presence of C8 aromatics

Vapor phase alkylation of ethylbenzene with ethanol to diethylbenzene is industrially relevant. Diethylbenzene is an important raw material for the conversion of divinyl benzene monomer. Conventionally, it is prepared from diacetophenone by reduction. It is also prepared by vapor phase alkylation of ethylbenzene with ethylene using zeolitic catalysts. The efficacy of dodecatungsotphosphoric acid (DTPA) supported on acid treated clay has been evaluated in the current work in the alkylation of ethylbenzene with 80% (w/w) ethanol. 15% (w/w) DTPA/K-10 clay was found to be an efficient and robust catalyst. The use of aqueous ethanol and a mixed C8 stream lowers the cost of production. A kinetic model is developed by studying the important process parameters with 15% (w/w) DTPA/K-10 as the catalyst.

Vapor phase alkylation of ethylbenzene with 80% aqueous ethanol, at mole ratio of 3:1, gives per pass conversion of 21.1% of ethylbenzene with 90.5% selectivity to diethylbenzene, over 15% (w/w) of dodecatungstophosphoric acid–K-10 clay at 250 °C. The catalyst is tolerant to xylenes and water.Figure optionsDownload as PowerPoint slide