The improvement of dechlorination efficiency remains an important challenge during co-hydrothermal carbonization (co-HTC) of polyvinyl chloride (PVC). In this work, co-HTC of biomass and PVC at different mixing ratios (30%–70%) and feed-water pH (3–11) was proposed to further improve the dechlorination efficiency. In terms of water solvent, the dechlorination efficiency of co-HTC process (87.83%–93.63%) was higher than that of individual HTC of polyvinyl chloride (87.44%). In case of organic acid/alkali solvents, the dechlorination efficiency further increased to 95.20% at pH = 5. Particularly, the hydrochars derived from co-HTC showed high fuel ratio (0.71–0.99) and their higher heating value reached approximately 29.16–32.83 MJ/kg. The TGA results showed that the combustion behaviors of hydrochars derived from co-HTC got better compared with that of hydrochar derived from PVC. Therefore, co-HTC can realize sustainable utilization of PVC towards clean solid fuels. This work also sheds light on the potential of organic acid in dechlorination treatment.

中文翻译：

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聚氯乙烯和玉米芯共水热碳化用于清洁固体燃料生产


提高脱氯效率仍然是聚氯乙烯（PVC）共水热碳化（co-HTC）过程中的一个重要挑战。在这项工作中，提出了生物质和PVC在不同混合比例（30%–70%）和给水pH值（3–11）下的共HTC，以进一步提高脱氯效率。就水溶剂而言，co-HTC工艺的脱氯效率（87.83%~93.63%）高于聚氯乙烯单独HTC工艺的脱氯效率（87.44%）。在有机酸/碱溶剂的情况下，在pH = 5时，脱氯效率进一步提高至95.20%。特别是，由co-HTC衍生的氢炭表现出高燃料比（0.71–0.99），其较高热值达到约29.16–32.83兆焦耳/公斤。 TGA结果表明，与PVC衍生的氢炭相比，co-HTC衍生的氢炭的燃烧行为更好。因此，co-HTC可以实现PVC向清洁固体燃料的可持续利用。这项工作还揭示了有机酸在脱氯处理中的潜力。