title: A novel reutilization method for waste printed circuit boards as flame retardant and smoke suppressant for poly (vinyl chloride).
abstract: In this study, a novel reutilization method for waste printed circuit boards (PCBs) as flame retardant and smoke suppressant for poly (vinyl chloride) (PVC) was successfully testified. A supercritical water oxidation (SCWO) process was applied to treat waste PCBs before they could be used as flame retardants of PVC. The results indicated that SCWO conditions had a significant effect on the flame retarding and smoke suppressing properties of waste PCBs for PVC. Cu2O, CuO, and SnO2 were the main active ingredients in waste PCBs-derived flame retardants. A conversion of Cu elements (Cu(0)→Cu(+)→Cu(2+)) during SCWO process with the increase of reaction temperature was found to be the key influence factor for the flame retarding properties of SCWO-treated PCBs. The experiment results also showed that there was a synergistic effect of flame retardancy between Cu(+) and Cu(2+). After the optimized SCWO treatment, SCWO-treated PCBs significantly improved the flame retardancy and smoke suppression of PVC. Limiting oxygen index (LOI) and char yield (CY) increased with increasing SCWO-treated PCBs content in PVC, while smoke density rating (SDR) and maximum smoke density (MSD) decreased markedly. The mechanical properties of PVC samples were influenced in different degree by adding different content SCWO-treated PCBs.
authors.affiliation: College of Ecological Environment and Urban Construction, Fujian University of Technology, Fuzhou 350108, People's Republic of China. Electronic address: xiu_chem@hotmail.com.
authors.forename: Fu-Rong
authors.initials: FR
authors.lastname: Xiu
authors.affiliation: College of Ecological Environment and Urban Construction, Fujian University of Technology, Fuzhou 350108, People's Republic of China.
authors.forename: Huiwei
authors.initials: H
authors.lastname: Weng
authors.affiliation: College of Ecological Environment and Urban Construction, Fujian University of Technology, Fuzhou 350108, People's Republic of China.
authors.forename: Yingying
authors.initials: Y
authors.lastname: Qi
authors.affiliation: College of Ecological Environment and Urban Construction, Fujian University of Technology, Fuzhou 350108, People's Republic of China.
authors.forename: Gending
authors.initials: G
authors.lastname: Yu
authors.affiliation: College of Ecological Environment and Urban Construction, Fujian University of Technology, Fuzhou 350108, People's Republic of China.
authors.forename: Zhigang
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, People's Republic of China.
authors.forename: Fu-Shen
authors.initials: FS
authors.lastname: Zhang
keywords: Flame retardant; Reutilization; Smoke suppressant; WEEE; Waste PCB