废弃环氧树脂电路板的热解机理及动力学研究  

Mechanism and kinetics of pyrolysis of discarded epoxy printed circuit boards

作　　者：湛志华[1] 丘克强[1] 

机构地区：[1]中南大学化学化工学院,湖南长沙410083

出　　处：《中南大学学报（自然科学版）》2011年第3期610-616,共7页Journal of Central South University:Science and Technology

基　　金：国家"863"计划项目(2006AA06Z375);广东省社会发展计划项目(2006A36703002)

摘　　要：采用热分析技术(TGA)研究废弃环氧树脂电路板在氮气气氛和真空条件下热解过程的反应机理和动力学行为。将热解过程分为2个阶段进行机理和动力学研究。研究结果表明:环氧电路板的热解过程第1步是失去水分和小分子物质,第2步是有机材料的裂解。氮气氛围和真空2种条件下裂解反应第1阶段遵循共同的机理函数,是以成核及核成长为控制步骤的A3机理,反应级数为3级;第2阶段都是以幂函数不均匀生长为控制步骤的C1.5机理;真空热解有利于降低反应的活化能;氮气氛围裂解反应各阶段的表观活化能和频率因子分别为:E1=239.95 kJ/mol,A1=1.94×1022 s-1;E2=130.73 kJ/mol,A2=1.88×1013 s-1;在真空条件下,裂解反应各阶段的表观活化能和频率因子分别为:E1=74.24 kJ/mol,A1=1.52×108 s-1;E2=41.64 kJ/mol,A2=5.16×1010 s-1。Reaction mechanism and kinetic behavior of discarded epoxy printed circuit board pyrolysis were studied by means of the thermogravimetric analysis（TGA） technique in nitrogen and vacuum conditions.The results show that there are two steps in the thermal decomposition of PCB.In the first step,some moisture and smaller molecules are lost.And then macromolecule pyrolysis in PCB take place in the second step.The second step can disassemble into two phases.The pyrolysis reaction of the first phase in nitrogen and vacuum conditions belongs to the A3 mechanism with nucleation and nuclei growth reaction as the control step.The second phase in nitrogen and vacuum belongs to the C1.5 mechanism with power law reaction as control steps.The apparent active energy of two phases is： 239.95,130.73 kJ/mol（in nitrogen）,74.24,41.64 kJ/mol（in vacuum） respectively,and the frequency factor is 1.94×1022 s-1,1.88×1013 s-1（in nitrogen）,1.52×108 s-1,5.16×1010 s-1（in vacuum） respectively.

关 键 词：电路板 热裂解 反应机理 动力学 

分 类 号：X705[环境科学与工程—环境工程]