A Review of Technology of Metal Recovery from Electronic Waste

Electronic waste, or e-waste, is an emerging problem with developed nations as with developing nations. In the absence of proper collection and disposal systems, aware‐ ness, 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 manage‐ ment of e-waste in general and their recycling and reuse in particular. Their recovery, recycle, and reuse have become mandatory. Research and develop‐ ment work on their recycling has led to several technological options. However, a close investigation of the options reveals that there is no universally acceptable mod‐ el for management of e-waste and they are still evolving. The technology for recy‐ cling depends on the economic status of the region along with several other factors. R&D efforts towards the management of e-waste and its recycling is seriously lack‐ ing 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 thermo‐ setting 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 plas‐ tics and processed for recovery of individual metals. It may be said that physical sep‐ aration techniques followed by metallurgical treatment is the best proposition for the 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.