Research advance on hydrothermal dechlorination technology for PVC waste plastics

doi:10.16085/j.issn.1000-6613.2024-0863

Abstract

Abstract:

Pyrolysis is one of the most promising technologies for the disposal of waste plastics. However, the polyvinyl chloride (PVC) in the mixed waste plastics is regarded as the bottleneck in the resource utilization of waste plastics for it can lead to serious excessive of chlorine in the product and equipment corrosion during pyrolysis. This paper first introduced the hazards of PVC in disposal, and comprehensively compared the advantages and disadvantages of the current PVC dechlorination technologies. Subsequently, the mechanism of PVC hydrothermal treatment for dechlorination and the process intensification of dechlorination by exogenous additives are revealed. Also, the reactors and scale-up strategies for PVC hydrothermal treatment are summarized, following by the introduction of application of products obtained by PVC hydrothermal. Finally, the existing problems in PVC hydrothermal dechlorination technology are pointed out, and the solutions and prospects are proposed, by which a guidance for the development of a harmless, resourceful and high-value utilization technologies of chlorine-containing mixed waste plastics can be obtained.

Key words: waste plastic, polyvinyl chloride, waste treatment, hydrothermal, dechlorination technology

摘要：

热解是当前废塑料最具前景的处置技术之一，但混合废塑料中的聚氯乙烯（PVC）在热解过程中会导致产物氯含量严重超标及设备腐蚀问题，成为了废塑料资源化利用过程中的关键问题。本文首先介绍了PVC处置过程的危害，综合对比了现有PVC脱氯技术的优劣。其次，着重围绕PVC水热脱氯技术，剖析了PVC水热处理过程的脱氯机理及外源添加物的强化脱氯机制，列举了PVC水热产物的利用、水热处理反应器及规模化应用情况。最后，指出了当前PVC水热脱氯技术中存在的问题，并针对性地提出了解决思路及展望，以期为含氯混合废塑料无害化、资源化及高值化利用技术的开发提供指导。

关键词: 废塑料, 聚氯乙烯, 废物处理, 水热, 脱氯技术

CLC Number:

X705

HAO Qingquan, SUI Lihua, LIU Jingru, ZHANG Shucai. Research advance on hydrothermal dechlorination technology for PVC waste plastics[J]. Chemical Industry and Engineering Progress, 2025, 44(7): 4117-4125.

郝清泉, 隋立华, 刘静如, 张树才. 聚氯乙烯废塑料水热脱氯技术研究进展[J]. 化工进展, 2025, 44(7): 4117-4125.

Figures/Tables 6

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