Methods of recycling polystyrene material comprising brominated contaminants

Method of recovering carbonaceous additives from a polystyrene waste comprising

• dissolving the polystyrene waste in a solvent mixture comprising about 50 wt % to about 90 wt % of a first solvent or a second solvent;
• and about 10 wt % to about 50 wt % of a hydrocarbon polystyrene non-solvent, to obtain a polystyrene/second solvent mixture and a solid comprising the carbonaceous additives,
• separating the polystyrene/second solvent mixture and the solid comprising the carbonaceous additives,
• washing the solid comprising the carbonaceous additives with a first solvent to obtain the carbonaceous additives and a first solvent solution, and
• optionally drying the carbonaceous additives,
• the first solvent being chosen from benzenes substituted with one or two substituents each chosen from C1 and C2 alkyl and mixtures thereof,
• the second solvent being chosen from benzenes substituted with one or two substituents each chosen from C1 to C4 alkyl, wherein at least one of the one or two substituents is isopropyl,
• the hydrocarbon polystyrene non-solvent being chosen from C5 to C8 hydrocarbon and mixtures thereof.