欢迎访问过程工程学报, 今天是

过程工程学报 ›› 2022, Vol. 22 ›› Issue (5): 680-688.DOI: 10.12034/j.issn.1009-606X.221119

• 研究论文 • 上一篇    下一篇

基于非等温法的废弃环氧树脂电路板热解动力学分析

丁桂珍1,2， 郑刘根1,2*， 吴盾3,4,5， 迟文飞4,5   

  1. 1. 安徽大学资源与环境工程学院，安徽 合肥 230601 2. 安徽省矿山生态修复工程实验室，安徽 合肥 230601 3. 中国科学技术大学地球和空间科学学院，安徽 合肥 230026 4. 安徽省煤田地质局勘查研究院，安徽 合肥 230088 5. 安徽省绿色矿山工程研究中心，安徽 合肥 230088
  • 收稿日期:2021-04-12 修回日期:2021-07-28 出版日期:2022-05-28 发布日期:2022-05-27
  • 通讯作者: 郑刘根 lgzheng@ustc.edu.cn
  • 作者简介:丁桂珍(1996-)，女，安徽省安庆市人，硕士研究生，环境科学专业，E-mail: X19201027@stu.ahu.edu.cn；郑刘根，通讯联系人，E-mail: lgzheng@ustc.edu.cn.
  • 基金资助:
    国家自然科学基金项目;安徽省重大科技攻关项目

Kinetics analysis of pyrolysis of waste epoxy printed circuit boards by non-isothermal method

Guizhen DING1,2,  Liugen ZHENG1,2*,  Dun WU3,4,5,  Wenfei CHI4,5   

  1. 1. School of Resources and Environmental Engineering, Anhui University, Hefei, Anhui 230601, China 2. Anhui Province Engineering Laboratory for Mine Ecological Remediation, Hefei, Anhui 230601, China 3. School of Earth and Space Sciences, University of Science and Technology of China, Hefei, Anhui 230026, China 4. Exploration Research Institute, Anhui Provincial Bureau of Coal Geology, Hefei, Anhui 230088, China 5. Anhui Province Green Mine Engineering Research Center, Hefei, Anhui 230088, China
  • Received:2021-04-12 Revised:2021-07-28 Online:2022-05-28 Published:2022-05-27

PDF

摘要： 热解技术在处理废弃电路板，回收电路板中的金属，实现树脂、玻璃纤维等非金属成分的资源化方面发挥愈来愈重要的作用，但目前对于不含任何电子元件、含少量铜箔的废弃环氧树脂电路板的热解机理研究尚不明确。为阐述其热解催化作用，采用同步热分析仪和气相色谱-质谱联用(GC-MS)仪对不同升温速率(5, 10, 15, 20℃/min)下电路板的热解特性及热解机理进行分析。结果表明，废弃电路板热解过程主要分为四个阶段：表面残余水蒸发或其他小分子散逸、环氧树脂侧链基团氧化、四溴双酚A的分解和热解残留物分解；运用Kissinger法、Flynn-Wall-Ozawa法及Friedman法等明确单一反应的热解区间并求解热分解反应动力学参数，最终得到指前因子1.14×1022 min-1和活化能218.533 kJ/mol；采用?atava-?esták法和主曲线法进行机理函数对比分析，最终表明废弃环氧树脂电路板适用随机成核与增长模型：Avrami-Erofeev方程模化。研究结果可为促进热解技术的应用提供理论支撑。

关键词: 热解动力学, 机理模型, 废弃电路板, 环氧树脂, 主曲线法

Abstract: The pyrolysis characteristics and pyrolysis mechanism of waste epoxy resin circuit boards containing a small amount of copper foil are mostly studied by a single "model matching method". To illustrate its pyrolysis catalysis, the pyrolysis characteristics and pyrolysis mechanism of the screened samples were analyzed by synchronous thermal analyzer and gas chromatography-mass spectrometry (GC-MS) at four different heating rates (5, 10, 15, 20℃/min), proposed a method to accurately calculate the "kinetic triplet". That is, firstly, two equal conversion methods were compared and analyzed to determine whether to follow a single pyrolysis reaction. Secondly, ?atava-?esták method and master curve method were used to select the appropriate mechanism model. Finally, the exact dynamic reaction order and mechanism function were obtained. The results showed that with the increase of heating rate, the residual residue in pyrolysis of waste circuit boards increased, indicating that the smaller the heating rate, the more complete the pyrolysis and the maximum rate of pyrolysis increased with the increase of heating rate. The pyrolysis process can be divided into four stages: the first stage (<150℃), evaporation of residual water on the surface or dissipation of other small molecules, the second stage (150~380℃), the third stage (380~500℃), the epoxy resin continued to decompose tetrabromobisphenol A, which formed small molecules and volatilized, and the fourth stage (>500℃), the pyrolysis residue decomposed slowly. Kissinger, Flynn-Wall-Ozawa and Friedman methods were used to solve the kinetic parameters of the thermal decomposition reaction of the sample, and finally the pre-exponential factor was 1.14×1022 min-1 and the activation energy was 218.533 kJ/mol. The mechanism function was compared and analyzed by ?atava-?esták method and master curve method, and finally the complete kinetic three factors were obtained. In addition, the relationship between activation energy and conversion rate proved that the waste epoxy resin circuit board can be modeled by Avrami-Erofeev equation (random nucleation and growth model) with reaction order of 5.4131: G(α)=[-ln(1-α)]5.4131.

Key words: pyrolysis kinetics, mechanism model, waste circuit boards, epoxylite, master curve method