Abstract: A process to purify t-butylstyrene from product containing substantial amounts of t-butylethylbenzene and small amounts of alkenyl-substituted styrene impurities by a combination of vacuum fractionation and vacuum evaporation in the presence a polymerization inhibitor, and treatment with a carbonaceous adsorbent. Such a product to be purified can be prepared by catalytically, oxidatively dehydrogenating over an alkaline pyrophosphate in the vapor phase t-butylethylbenzene containing about 95 wt. % or more of the p-isomer which can be made by alkylating ethylbenzene with isobutylene in a controlled manner in the presence of cooled concentrated sulfuric acid.

Abstract: Described are magnesium compound-impregnated catalyst compositions comprising a gallium-modified, crystalline silica molecular sieve, essentially free of aliminum, composited in an inorganic matrix. Said compositions are useful fro hydrocarbon conversion, particularly the selective ethylation of toluene in which they exhibit extremely high paraselectivity at an excellent percent conversion.