A process for recycling polystyrene waste, comprising: dissolving said polystyrene waste in p-cymene to obtain a polystyrene/p-cymene mixture; adding said polystyrene/p-cymene mixture to a first portion of hydrocarbon polystyrene non-solvent under conditions to obtain precipitated polystyrene and a first portion of hydrocarbon waste solution, wherein said conditions to obtain said precipitated polystyrene and said first portion of hydrocarbon waste solution comprise adding said polystyrene/p-cymene mixture to said first portion of hydrocarbon polystyrene non-solvent at the boiling point of said hydrocarbon polystyrene non-solvent and agitating for a time for diffusion of said p-cymene from said polystyrene/p-cymene mixture into said hydrocarbon polystyrene non-solvent to proceed to a sufficient extent; separating said precipitated polystyrene from said first portion of hydrocarbon waste solution; optionally repeating said dissolving, adding and separating; washing said precipitated polystyrene with a second portion of hydrocarbon polystyrene non-solvent under conditions to obtain washed polystyrene and a second portion of hydrocarbon waste solution, wherein said conditions to obtain said washed polystyrene and said second portion of hydrocarbon waste solution comprise adding said second portion of hydrocarbon polystyrene non-solvent to said precipitated polystyrene at the boiling point of said hydrocarbon polystyrene non-solvent and agitating for a time for diffusion of said p-cymene from said precipitated polystyrene into said hydrocarbon polystyrene non-solvent to proceed to a sufficient extent; separating said washed polystyrene from said second portion of hydrocarbon waste solution; washing said washed polystyrene with a third portion of hydrocarbon polystyrene non-solvent under conditions to obtain twice-washed polystyrene and a third portion of hydrocarbon waste solution, wherein said conditions to obtain said twice-washed polystyrene and said third portion of hydrocarbon waste solution comprise adding said third portion of hydrocarbon polystyrene non-solvent to said washed polystyrene at the boiling point of said hydrocarbon polystyrene non-solvent and agitating for a time for diffusion of said p-cymene from said washed polystyrene into said hydrocarbon polystyrene non-solvent to proceed to a sufficient extent; separating said twice-washed polystyrene from said third portion of hydrocarbon waste solution; and optionally drying said twice-washed polystyrene to obtain dried polystyrene, wherein said first portion of hydrocarbon polystyrene non-solvent, said second portion of hydrocarbon polystyrene non-solvent and said third portion of hydrocarbon polystyrene non-solvent comprise, consist essentially of or consist of a hydrocarbon polystyrene non-solvent having a boiling point at 1 atm of pressure of from 98°C to 110°C or 105°C to 110°C. dissolving said polystyrene waste in p-cymene to obtain a polystyrene/p-cymene mixture; adding said polystyrene/p-cymene mixture to a first portion of hydrocarbon polystyrene non-solvent under conditions to obtain precipitated polystyrene and a first portion of hydrocarbon waste solution, wherein said conditions to obtain said precipitated polystyrene and said first portion of hydrocarbon waste solution comprise adding said polystyrene/p-cymene mixture to said first portion of hydrocarbon polystyrene non-solvent at the boiling point of said hydrocarbon polystyrene non-solvent and agitating for a time for diffusion of said p-cymene from said polystyrene/p-cymene mixture into said hydrocarbon polystyrene non-solvent to proceed to a sufficient extent; separating said precipitated polystyrene from said first portion of hydrocarbon waste solution; optionally repeating said dissolving, adding and separating; washing said precipitated polystyrene with a second portion of hydrocarbon polystyrene non-solvent under conditions to obtain washed polystyrene and a second portion of hydrocarbon waste solution, wherein said conditions to obtain said washed polystyrene and said second portion of hydrocarbon waste solution comprise adding said second portion of hydrocarbon polystyrene non-solvent to said precipitated polystyrene at the boiling point of said hydrocarbon polystyrene non-solvent and agitating for a time for diffusion of said p-cymene from said precipitated polystyrene into said hydrocarbon polystyrene non-solvent to proceed to a sufficient extent; separating said washed polystyrene from said second portion of hydrocarbon waste solution; washing said washed polystyrene with a third portion of hydrocarbon polystyrene non-solvent under conditions to obtain twice-washed polystyrene and a third portion of hydrocarbon waste solution, wherein said conditions to obtain said twice-washed polystyrene and said third portion of hydrocarbon waste solution comprise adding said third portion of hydrocarbon polystyrene non-solvent to said washed polystyrene at the boiling point of said hydrocarbon polystyrene non-solvent and agitating for a time for diffusion of said p-cymene from said washed polystyrene into said hydrocarbon polystyrene non-solvent to proceed to a sufficient extent; separating said twice-washed polystyrene from said third portion of hydrocarbon waste solution; and optionally drying said twice-washed polystyrene to obtain dried polystyrene,