热解条件对废印刷电路板真空热解气相产物的影响

Effect of Pyrolysis Conditions on Vacuum Pyrolysis Gaseous Product from Waste Printed Circuit Board

用管式炉对废印刷电路板环氧树脂粉末进行真空热解,通过GC/MS和IC对冷凝后气相中的有机和无机组份进行分析,考察了真空度、升温速率和终温对气相产物成份的影响。研究表明,冷凝后气相中主要有机组份为苯酚和苯系物,主要无机组份为HBr、NO_2、SO_2;随着真空度的提高,气相产率降低,苯系物和HBr的含量增加,苯酚和NO_2、SO_2的含量减少;加快升温速率导致气相产率降低,苯系物的含量增加,苯酚含量减少;提高终温使气相中苯酚和苯系物的含量降低,HBr、NO_2和SO_2的含量增加。为了降低气相产物对环境的影响,综合考虑最佳热解条件为真空度0.09 MPa、升温速率10℃/min、终温500℃。

This study focused on the effect of vacuum degree, heating rate and final temperature on the constituents of gaseous products, by means of vacuum pyrolysing the epoxy resin powder of waste printed circuit board with tube furnace and analyzing the organic and inorganic constituents in the condensated gaseous products by using GC/MS and IC. The results indicate that the major organic constituents are phenol and benzene series and the major inorganic constituents are HBr, NO_2,SO_2. With the increase of vacuum degree, gaseous productive rate is reduced and the contents of benzene series and HBr get increased, while the content of phenol, NO_2 and SO_2is reduced. The acceleration of heating rate results in the decrease of gaseous production rate, the increment of the content of benzene series and the reduction of the content of phenol.Heightening the final temperature leads to the content reduction of phenol and benzene series, the content increment of HBr,NO_2 and SO_2. In order to reduce the gas phase product＇s impact on environment, for overall consideration, it is concluded that the optimum pyrolysis conditions is vacuum degree of 0.09 MPa, the heating rate of 10 ℃ /min and the final temperature of 500 ℃.