A Review of Technology of Metal Recovery from Electronic Waste

Abstract

Electronic waste, or e-waste, is an emerging problem with the developed nations as with developing nations. In the absence of proper collection and disposal systems, awareness and proper regulations, the problem is rather more acute in developing nations. These wastes are environmentally hazardous on one hand and valuable on the other. They contain substantial amount of metal value including precious metals. Personal computers are the biggest contributors to e-waste followed closely by televisions and mobile phones. The growth in their consumption pattern indicates a manifold increase in the volume of e-waste and calls for immediate attention to the management of e-waste in general and their recycling and reuse in particular. Their recovery, recycle and reuse have become mandatory. Research and development work on their recycling has led to several technological options. However, a close investigation of the options reveals that there is no universally acceptable model for management of e-waste and they are still evolving. The technology for recycling depends on the economic status of the region along with several other factors. R&D efforts towards management of e-waste and its recycling is seriously lacking in India. There are three main constituents of e-waste, namely, glass, plastics and metals. The glass may be re-melted for production of glass or for recovery of lead. The thermosetting plastics are difficult to recycle. The other types of plastics can be recycled for use as fuels or production of chemicals. The metals may be separated from the plastics and processed for recovery of individual metals. It may be said that physical separation techniques followed by metallurgical treatment is the best proposition for recovery of metals. Detailed technology development needs to be taken up for the recycling of e-waste that may serve the interest of the region best.