Abstract
The reduction of plastic waste and the implementation of chemical recycling are strongly recommended, but appropriate treatment methods for halogenated plastics such as polyvinyl chloride (PVC) have not yet been fully established. Results of this study contribute to the effective chemical recycling of PVC by hydrothermal processing. The reaction behavior of PVC was investigated under hydrothermal conditions to clarify the dechlorination process, surface morphological evolution, and product structure. Three distinct reaction environments were applied: liquid phase (stirred), liquid phase (static), and vapor phase. The results indicate that the reaction products’ morphology is influenced strongly by both solvents or additives and the reaction environment. The reactivity in aqueous ammonium solutions ((NH2)2CO and NH4OH) and amine additives (triethylamine and polyethylenimine) under stirred conditions was notably effective. The findings demonstrate that different physical and chemical changes imposed on PVC during the initial stages of the reaction yield marked variations in dechlorination behavior. Furthermore, these changes affect the morphology and structure of the resulting product. Various controls of hydrothermal reaction conditions suggest the usefulness of the chemical recycling of PVC.
