Patent 10894870 was granted and assigned to Purdue Research Foundation on January, 2021 by the United States Patent and Trademark Office.
Methods of recovery of pristine polymers and hydrocarbon mixtures from a sorted waste feedstock or mixtures of waste feedstock, which are with or without organic additives are disclosed. The methods include Sequential Selective Extraction and Adsorption (SSEA), Hydrothermal Processing (HTP), and a combination of SSEA and HTP. Exemplarily, SSEA includes selecting a first solvent (S1), inputting the S1 and a sorted feedstock free of organic additives into an extractor, heating, waiting, and separating insolubles forming a pristine polymer solution. Exemplarily, HTP includes inputting a hydrothermal solvent and a sorted feedstock free of organic additives into a reactor, heating to form subcritical or supercritical H2O, waiting, causing thermal depolymerization to produce a slurry, cooling, venting formed gases and separating the hydrocarbon mixture.