Currently, the number of the waste printed circuit boards (WPCB) is increasing. The technologies of extracting and reclaiming of the value of the metallic fraction of WPCB have been used widely because of the major economic driving force. But the non-metallic fractions (NMFs), which take up almost 70wt% of waste WPCB, were mainly treated by combustion or land filling in the past. However, combustion of the NMFs will cause the formation of highly toxic polybrominated dibenzodioxins and dibenxofurans (PBDD/Fs). Land filling of the NMFs will lead to secondly pollution that caused by heavy meatals and brominated flame retardants (BFRs) leaching to the groundwater. Therefore, recycling of the NMFs from waste PCBs is drawing more and more attention from the public and the governments. How to recycle the NMFs environmental soundly has become a significant topic in recycling of WPCB. This paper briefly introduced that the damage of WPCB and the recycling methods of epoxy resin. The method was established for recycling of WPCB by using solvent extraction. And the optimal conditions were attained through experiments: the reaction temperature was 80°C、the reaction time was 3h、the concentration of nitrate acid was 8 mol/l, the amount of nitrate acid : the quality of WPCB was 50ml/10g.
Kinetic Study of the Pyrolysis of Waste Printed Circuit Boards Subject to Conventional and Microwave Heating
