Depolymerization method for resource recovery from polymeric wastes

Abstract

Polymeric feedstocks, such as scrap or waste tires, rubber, and plastics, in a size range of -6 to +25 mesh are washed with an organic solvent to remove stabilizing additives which have migrated to the surface of the polymer particles, thus eliminating the stabilizers from participation in subsequent reactions and allowing the final production of more pure monomeric products. The polymer particles are exposed to ozone under conditions to cause stress cracking, fissuring and cleavage of the polymer feedstock particles. The ozonated polymer particles are depolymerized to produce one or more monomeric compounds, with the reaction taking place rapidly and occurring in the presence of a system of one or more catalysts which may be metallic salts. The depolymerization is accomplished under conditions of elevated temperatures and reduced pressure, the conditions being less severe than those conditions associated with thermal pyrolysis. The monomeric compounds are recovered by conventional means from otherwise waste polymers and are recycled. Other products of this invention may be collected and recycled or disposed of with no adverse impact on the environment.

Dependencies are inferred from the claim text.