Supercritical fluid extraction for purification of waxes derived from polyethylene and polypropylene plastics.

Polyethylene (PE) and polypropylene (PP) feedstock contain various additives, such as fillers and colorants, which either degrade or carry through the depolymerization process; thereby causing intense dark colors and a pungent petroleum odor. The combination of color and odor imposes several challenges, limiting the potential markets of the wax products. This study put emphasis on the development of an innovative and environmentally sustainable process based on supercritical fluid extraction (SCFE) to remove organic and inorganic contaminants that cause color and odor in waxes derived from recycled polymers.