废印制线路板真空热解产物分析

Analysis of Vacuum Pyrolysis Products from Waste Printed Circuit Board

在自行设计的间歇式固定床真空热解装置中热解废印制线路板(PCB),对热解产物进行了分析。在热解温度为550℃、热解压力为20 kPa、恒温时间为60 min的条件下,得到的热解产物质量分数为:热解渣70%;热解油3%～4%;不可冷凝热解气26%～27%。经气相色谱-质谱联用(GC-MS)分析,热解油经常压蒸馏后得到的低沸点液态油中含有29种化合物,主要有苯酚、对异丙基酚、3-乙基酚、4-甲酚及2-溴苯酚,还含有少量含溴化合物和含氯化合物。热解油经简单的蒸馏就可达到回收酚类化合物的目的。热解渣经风选可实现铜与黏附有碳黑的玻璃纤维的分离,其中铜质量分数约30%,黏附有碳黑的玻璃纤维质量分数约70%。

Waste printed circuit board （PCB） was pyrolyzed in a self-developed fixed bed batch vacuum pyrolyzer and the pyrolysis products were analyzed. Under the conditions of pyrolysis temperature 550℃, pyrolysis pressure 20 kPa and constant temperature time 60 min, the mass fractions of the products are as follows： pyrolysis residue 70%, pyrolysis oil 3 % -4%, uncondensable pyrolysis gas 26% - 27%. The GC-MS analysis results show that the low-boiling point liquid from atmospheric distillation of the pyrolysis oil contains 29 kinds of compounds, such as phenol, p-isopropyl phenol, 3-ethyl phenol, 4-cresol, 2-bromine phenol and a few of bromine compounds and chlorine compounds. It indicates that phenol compounds in the pyrolysis oil can be recovered by simple distillation. The mass fraction of copper separated from carbon black-covered glass fiber by wind selection is about 30%, and that of the carbon black-covered glass fiber is about 70%.