Co-hydrothermal carbonization of polyvinyl chloride and corncob for clean solid fuel production

• Published in: Bioresource technology 2020-04, Vol.301, p.122763-122763, Article 122763
• Main Authors: Lu, Xiaoluan, Ma, Xiaoqian, Chen, Xinfei, Yao, Zhongliang, Zhang, Chaoyue
• Format: Article
• Language: English
• Subjects: Biomass; Carbon; Corncob; Dechlorination efficiency; Fuel properties; Hydrothermal carbonization; Polyvinyl Chloride; Temperature; Zea mays
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2020.122763

•The effect of corncob/PVC mass ratio and feedwater pH during co-HTC was studied.•The experimental efficiency was higher than calculated value in dechlorination.•The addition of corncob waste and citric acid can improve the hydrochars quality. 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.