Meaning
Hydrocarbon feedstocks recovered through thermal or chemical breakdown of post-consumer plastic waste provide purified monomers and intermediate oils for polymerization. Unlike mechanical flakes, chemical recyclate undergoes pyrolysis, gasification or solvolysis to sever polymer chains down to chemical intermediates identical to petrochemical inputs. The classification applies strictly to chemically cracked and repolymerized outputs, terminating where mechanically sorted, melted and regranulated resins are defined.
Depolymerisation Yield
Conversion mass balance metrics track the fraction of contaminated mixed polymer waste converted into usable liquid hydrocarbons or purer monomers. Solvolysis processes breaking down polyethylene terephthalate yield purified dimethyl terephthalate or bis(2-hydroxyethyl) terephthalate while filtering out colorants and mineral fillers. Impurities such as flame retardants, polyvinyl chloride traces and heavy organic foils reduce overall reaction yields.
Thermal pyrolysis reactors face char formation that fouls pipe surfaces and extracts carbon value from the liquid recovery stream. Secondary distillation purifies pyrolytic oils before steam cracking occurs.
Feedstock Parity
Molecular equivalence grants virgin-grade mechanical performance to resins synthesized from chemical recyclate. Injection moulders running polyolefins from mass-balanced cracking streams observe melt flow rates, tensile properties and optical clarity identical to fossil-based polymers. Regulatory barriers for food contact packaging disappear under certified monomer reconstruction.
Processing technicians run standard injection velocity profiles, packing pressures and cooling cycles without adjusting for degraded polymer chains. Regrind limits on customer prints accept repolymerized materials without technical deviation waivers.
Contamination Boundary
Halogenated additives and non-polyolefin contaminants mark the strict technical limit where chemical recycling units reject inbound waste bales. Organochlorines degrade pyrolysis catalysts and generate corrosive hydrochloric acid within cracking tubes. Moulders supplying post-industrial scrap to depolymerization plants must separate halogenated polymers, metal inserts and heavily crosslinked resins before dispatch.
Chemical recyclate sourcing hinges on rigorous upstream sorting to prevent catalyst poisoning during feedstock reconstitution.
