Ball-milling technology is adopted for the debromination of nonmetallic particles of waste printed circuit boards. During the ball-milling process, too short ball-milling time causes insufficient debromination. Excessive ball-milling leads to the waste of resources and the destruction of the main structure of nonmetallic particles resin, unfavorable for the secondary utilization. However, how to determine debromination time of nonmetallic particles in ball-milling process has not been detailed studied. In this study, the ball-milling energy was coupled with the degradation energy of pentabromodiphenyl ether molecule to compute the time for each chemical bond to break. The ball-milling model was used to accurately compute effective mechanical ball-milling energy (1.234×10^-3 J) generated by a single collision. The average bond energies of C-O bond, C-Br bond and C-H bond (261.24, 302.05 and 489.50 kJ/mol) were analyzed by density functional theory. Under the conditions of 220 r/min and 1.2 g nonmetallic particles and NZVI (4:1). The C-O bond, C-Br bond, and C-H bond fractured completely in turn at 2.25 h, 7.23 h (optimal debromination time), and 11.72 h. Based on the analysis of debromination pathways, it inferred that H₂O, HBr、CH₃Br, CH₄, FeBr₂, and graphite were generated. This paper develops a novel idea of the schedule of debromination time of nonmetallic particles, contributing to the directional removal of organic pollutants by ball-milling.

采用球磨技术对废印刷电路板的非金属颗粒进行脱溴处理。在球磨过程中，太短的球磨时间会导致脱溴不足。过度的球磨会浪费资源，破坏非金属颗粒树脂的主要结构，不利于二次利用。然而，如何确定球磨过程中非金属颗粒的脱溴时间尚未进行详细研究。在这项研究中，将球磨能与五溴二苯醚分子的降解能结合起来，计算出每个化学键断裂的时间。球磨模型用于精确计算有效的机械球磨能量（1.234×10 ^-3 J）由一次碰撞产生。用密度泛函理论分析了CO键，C-Br键和CH键的平均键能（261.24、302.05和489.50 kJ / mol）。在220 r / min和1.2 g非金属颗粒和NZVI（4：1）的条件下。CO键，C-Br键和CH键依次在2.25h，7.23h（最佳脱溴时间）和11.72h处完全断裂。通过对脱溴途径的分析，推断出生成了H ₂ O，HBr，CH ₃ Br，CH ₄，FeBr ₂和石墨。本文提出了一种非金属颗粒脱溴时间安排的新思路，有助于球磨法定向去除有机污染物。