Effects of transition metal oxides on pyrolysis properties of PVC

Polyvinyl chloride (PVC) produces a large amount of solid wastes because of its wide use. How to dispose quickly and harmlessly of the PVC solid wastes and turn into a resource is currently a major problem. In this paper, the experimental material was PVC. Thermogravimetric analyzer (TG) and pyrolysis-gas chromatography-mass spectrometer (Py-GC-MS) were used to study the pyrolysis characteristics of PVC with transition metal oxide. The effect of in-situ pyrolysis of PVC in N-2 on transition metal oxides was studied in a SX3-4-10A muffle furnace. The composition of tars captured by the cold trap was analyzed by GC-MS. The residual carbon after pyrolysis was analyed by scanning electron microscope (SEM) and XRD. The results of PY-GC-MS and GC-MS showed that the two stages of PVC pyrolysis were advanced with the transition metal oxide.The decomposition peak temperature increased to make PVC pyrolysis more complete. The transition metal oxide reduced significantly the production of benzene, toluene, indene, naphthalene, anthracene and other compounds during the pyrolysis of PVC. The results of SEM and XRD showed that transition metal oxides absorbed HCl produced by pyrolysis and increased the amount of residual carbon in the system. These studies provided a theoretical basis for the pyrolysis rapidly of PVC. (C) 2020 Published by Elsevier B.V. on behalf of Institution of Chemical Engineers.