METHOD FOR RECOVERING STYRENE MONOMER FROM WASTE POLYSTYRENE WHICH CONTAINS FLAME RETARDANT

摘要

PURPOSE: A method for recovering a styrene monomer from waste polystyrene which contains a flame retardant, is provided to improve the amount, selectivity and recovery yield of a styrene monomer by inactivating the flame retardant or its pyrolyzed side products, while promoting the pyrolysis reaction. CONSTITUTION: The method for recovering a styrene monomer from waste polystyrene comprises pyrolysis of the waste polystyrene in the presence of a catalyst, wherein the catalyst has 8-14 of a Bronsted basicity in an aqueous solution, and the pyrolysis is carried out at 200-1000 deg.C for 1-2 hours in a reactor(2) installed in a heating furnace(1). The catalyst is selected from hydroxide, carbonate, phosphate and borate of alkali metal or alkali earth metal.