| abstract |
A method for purifying polymers made from depolymerization of plastic can include selecting a polymer for purification, adding the polymer to a reaction vessel with a solvent, heating the mixture to promote migration of contaminants from the polymer to the solvent, performing an extraction technique to remove contaminants, depressurizing the reaction vessel to isolate a purified polymer, and allowing the purified polymer to cool. In some embodiments, the polymer is a polyethylene polymer. In other embodiments, the polymer is a polypropylene polymer. In some embodiments, the polymer is a polystyrene polymer. In some embodiments, the extraction technique is supercritical fluid extraction using supercritical CO2 as a solvent. Parameters including temperature, pressure, duration, agitation rate, starting solvent volume, and co-solvent addition for supercritical fluid extraction can be selected based on the properties of the polymer to be purified. The method can remove contaminating organic and inorganic compounds from the polymers. |