Research on the pyrolysis kinetics of resin powder on waste printed circuit board with different particle sizes at different heating rates: inspiration for the pyrolysis mechanism

• Published in: Journal of thermal analysis and calorimetry Vol. 147; no. 14; pp. 8047 - 8059
• Main Authors: Wu, Dun, Ding, Guizhen, Chi, Wenfei, Jiang, Longjin
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01.07.2022; Springer; Springer Nature B.V
• Subjects: Activation energy; Analysis; Analytical Chemistry; Chemistry; Chemistry and Materials Science; Circuit boards; Circuit components; Circuit printing; Decomposition; Decomposition reactions; Electronic components; Electronic components industry; Epoxy resins; Glass fiber reinforced plastics; Growth models; Heating; Inorganic Chemistry; Measurement Science and Instrumentation; Metal foils; Nucleation; Oxidation; Particle size; Physical Chemistry; Polymer Sciences; Powders; Printed circuit boards; Printed circuits; Pyrolysis; Recycling; Recycling (Waste, etc.); Tetrabromobisphenol A; Thermal decomposition; Waste management; Resin powder; Particle size; Waste printed circuit board; Pyrolysis kinetics; Heating rate
• ISSN: 1388-6150; 1588-2926
• DOI: 10.1007/s10973-021-11102-9

Pyrolysis technology plays an increasingly important role in treating waste circuit boards, recycling metals in circuit boards, and recycling non-metallic components such as resins and glass fibers. However, the pyrolysis mechanism of printed circuit board (PCB) without any electronic components and with a small amount of copper foil is not comprehensive at present. The pyrolysis characteristics and pyrolysis mechanism were studied under different particle size conditions and different heating rates. The study found that the pyrolysis of waste printed circuit board (PCB) resin powder can be divided into four stages: evaporation of residual water on the surface or dissipation of other small molecules, oxidation of side chain groups of epoxy resin, decomposition of tetrabromobisphenol A and decomposition of pyrolysis residues. Kissinger, Flynn–Wall–Ozawa (FWO), Tang and other methods were used to solve the kinetic parameters of thermal decomposition reaction of samples, and it was found that the activation energy and pre-exponential factor of large particles (0.5–0.9 mm) are lower than those of small particles (< 0.5 mm). In addition, the experimental curve determined by z ( α ) master plots method mainly accords with Mampel power model (P3): G α = α 1 2 , and random nucleation and subsequent growth model (Avrami-Erofeev A2): G α = - ln 1 - α 1 2 in the main pyrolysis interval.