Kinetic study on the slow pyrolysis of nonmetal fraction of waste printed circuit boards (NMF-WPCBs). Issue 8 (August 2020)

• Record Type: Journal Article
• Authors: Yao, Zhitong; Xiong, Jingjing; Yu, Shaoqi; Su, Weiping; Wu, Weihong; Tang, Junhong; Wu, Daidai
• Is Part Of: Waste management & research. Volume 38:Issue 8(2020:Aug.)
• Page Start: 903
• Page End: 910
• Publication Date: 2020-08
• Subjects: Electronic waste -- pyrolysis kinetics -- model-free method -- distributed activation energy model -- Criado method; Factory and trade waste -- Periodicals; Refuse and refuse disposal -- Periodicals; Municipal engineering -- Periodicals; Déchets industriels -- Périodiques; Déchets -- Élimination -- Périodiques; Génie urbain -- Périodiques; 628
• DOI: 10.1177/0734242X19896630
• Languages: English
• ISSNs: 0734-242X

Abstract

In this study, the pyrolysis behaviour of nonmetal fraction of waste printed circuit boards (NMF-WPCBs) was studied based on five model-free methods and distributed activation energy model (DAEM). The possible decomposition mechanism was further probed using the Criado method. Thermogravimetric analysis indicated that the NMF-WPCBs pyrolysis process could be divided into three stages with temperatures of 37–330°C, 330–380°C and 380–1000°C. The mass loss at different heating rate was determined as 26.85–29.98%, 13.47–24.21% and 20.43–23.36% for these stages, respectively. The activation energy ( Eα ) from various model-free methods first increased with degree of conversion ( α ) increasing from 0.05 to 0.275, and then decreased beyond this range. The coefficient ( R ) from the Flynn–Wall–Ozawa (FWO) method was higher, and the resulting Eα fell into the range of 214.947–565.660 kJ mol −1 . For the DAEM method, the average Eα value was determined as 337.044 kJ mol −1, comparable with 329.664 kJ mol −1 from the FWO method. The thermal decomposition kinetics of NMF-WPCBs could be better described by the second-order reaction.