Recent developments and perspective of the spent waste printed circuit boards

Mechano-microbial systems: An ecofriendly approach for copper bioleaching from waste printed circuit board

Waste printed circuit board (PCB) is attracting serious concerns because the recycling of its valuable metallic portion is made difficult by the existence of hazardous substances. The objective of the present study was to develop a simplified approach for copper bioleaching from waste PCB. In this context, we intended mechano-microbial systems symbolized as SET-I (spore suspension + potato dextrose broth medium + waste PCB powder), SET-II (pre-cultured until the logarithmic phase, without waste PCB powder), and SET-III (fungal metabolites produced at stationary phase). The results of bioleaching studies showed that the developed method achieved the highest copper leaching of 85% by the SET-III approach. This study provides an insight for bioleaching copper from waste PCB. Furthermore, this approach can be established as an ecofriendly method for copper bioleaching by using an integrated system.

Evaluating waste printed circuit boards recycling: Opportunities and challenges, a mini review

Rapid generation of waste printed circuit boards has become a very serious issue worldwide. Numerous techniques have been developed in the last decade to resolve the pollution from waste printed circuit boards, and also recover valuable metals from the waste printed circuit boards stream on a large-scale. However, these techniques have their own certain specific drawbacks that need to be rectified properly. In this review article, these recycling technologies are evaluated based on a strength, weaknesses, opportunities and threats analysis. Furthermore, it is warranted that, the substantial research is required to improve the current technologies for waste printed circuit boards recycling in the outlook of large-scale applications.

Integrated bioleaching of copper metal from waste printed circuit board-a comprehensive review of approaches and challenges

Waste electrical and electronic equipment (e-waste) is the most rapidly growing waste stream in the world, and the majority of the residues are openly disposed of in developing countries. Waste printed circuit boards (WPCBs) make up the major portion of e-waste, and their informal recycling can cause environmental pollution and health risks. Furthermore, the conventional disposal and recycling techniques-mechanical treatments used to recover valuable metals, including copper-are not sustainable in the long term. Chemical leaching is rapid and efficient but causes secondary pollution. Bioleaching is a promising approach, eco-friendly and economically feasible, but it is slower process. This review considers the recycling potential of microbes and suggests an integrated bioleaching approach for Cu extraction and recovery from WPCBs. The proposed recycling system should be more effective, efficient and both technically and economically feasible.