Styrene

Abstract

Fresh and recycle ethylbenzene is preheated and fed with superheated steam to the reactor at a temperature of 600-620'C. Steam to ethylbenzene molar ratio is 12-15 to one. The reaction occurs adiabatically over a fixed catalyst bed, with 60 percent conversion, and 87-89 percent styrene into aqueous and organic phases. The organic phase, containing styrene, ethyl benzene, benzene, toluene and some higher boiling tar is first charged to the splitting column in which benzene, toluene and some ethylbenzene is taken overhead. The bottom is distilled under high vacuum to separate the unreacted ethyl benzene from the product styrene and tar. The final fractionation involves the recovery of polymer grade styrene. Renzene from the splitting column is further purified and recycled to the alkylation section of the plant.