Co-pyrolysis characteristics of different reworked synthetic polymer types

Reworked synthetic polymers (RSPs) are industrial raw materials obtained from waste synthetic polymer (WSP) through physical or chemical means. Different reworked synthetic polymers have different pyrolysis characteristics and synergistic reactions during co-pyrolysis process. The effect of reworked polyamide 6 (PA6), thermoplastic elastomer (TPE), black polypropylene (PP1) and green polypropylene (PP2) co-pyrolysis on the yield and quality of pyrolysis products has been conducted. The results show that co-pyrolysis promotes the degradation of RSPs into more gases. Co-pyrolysis improves the light component of liquid oils and reduces the O content, which is beneficial for liquid fuels. Except for TPE + PP2, co-pyrolysis of RSPs increased di-aromatics, poly-aromatics and aromatic compounds. TPE + PP2 and PP1+PP2 produced high aliphatic compounds including the long chain aliphatic compounds without sufficient degradation, which resulted in the contents of over C 20 were high. In the pyrolysis gases , the relative content of H 2 was increased in all mixed RSPs co-pyrolysis, which can be used as clean fuels. The X-ray diffraction (XRD) analysis shown that new components were found and old components disappeared in co-pyrolysis, indicating chemical reaction had occurred between two different types of RSPs.