METHOD FOR PREPARING VINYL AROMATIC MONOMER

摘要

PURPOSE: Provided is a method for preparing a vinyl aromatic monomer which can inhibit a clogging phenomenon in condenser after dehydrogenation of alkyl aromatic compound and improve a conversion of vinyl aromatic monomer, continuous driving period, and stability of continuous driving. CONSTITUTION: The method comprises the steps of: (i) dehydrogenating at least one of alkyl aromatic compounds to form a mixture of vinyl aromatic monomer and byproduct in the presence of dehydrogenation catalyst in at least one dehydrogenation reactor(into which steam is injected); (ii) heat exchanging the vapor mixture(effluent) and flowing the effluent in desuperheater(12) installed in a condenser; (iii) condensing the effluent in the desuperheater to obtain condensate; (iv) transferring the condensate to storage tank of mixture product through a plurality of drain units(13,14,15,16); and (v) transferring a noncondensate in the condenser to fin tube(17) connected to the condenser, together with gas components.