Non-Metallic Materials from Waste Printed Circuit Boards (PCBs): Characteristics, Environmental Risk and Recycling

Printed circuit boards (PCBs) are the typical and fundamental components of almost all electric and electronic equipments. The mechanical and physical treatment of PCBs generates a large amount of non-metallic materials and thus there is an urgent need to develop alternative treatment methods for them. In this study, the characteristics and environmental risk of non-metallic materials were analyzed. The current recycling methods were investigated as well. The results showed that their chemical components were distinct for the glass fiber/epoxy laminated boards and paper/phenolic laminated boards. The presence of bromine, chlorine, copper, chromium and lead would pose a threat to the environment during its recycling. The current recycling methods included landfill, preparing composites and building materials, pyrolysis and combustion. These methods had their own distinct advantages and disadvantages. The comparative analysis indicated that preparing composites may be an alternative recycling method. Molten salt oxidation (MSO) technology is prospective and need be further studied.