Research Progress on Pyrolysis Dechlorination Technology of PVC and Its Mixed Plastics
Polyvinyl chloride(PVC),the most widely used halogen-containing plastic,presents challenges in terms of the emission of dangerous gases like chlorinated hydrocarbons and dioxins during the recycling process,as well as damage to equipment and pipelines.Pyrolysis technology has the potential to both dechlorinate PVC-containing waste plastics for safe disposal and transform waste into valuable chemicals and fuels,thereby enhancing product yield and quality.Pyrolysis technology is one of the promising industrial technologies for waste plastic treatment.The paper focuses on the research progress of pyrolysis dechlorination technology at home and abroad.It comprehensively sorts out the dechlorination mechanisms of different technologies,including stepwise pyrolysis,adsorption pyrolysis,catalytic pyrolysis,co-pyrolysis,and combined pyrolysis.Additionally,it summarises various factors that affect the dechlorination effect of pyrolysis,such as the types and modes of action of additives,placement modes,and types of admixtures.It analyses the advantages and disadvantages of each technology and its industrial application prospects to provide a reference for the industrialisation of dechlorination and recycling of waste plastics.