Circular bioeconomy and environmental benignness through microbial recycling of e-waste: A case study on copper and gold restoration.

This study has attempted to ascertain the linkages between circular bio-economy (CirBioeco) and recycling of electronic (e-)waste by applying microbial activities instead of the smelter and chemical technologies. To build the research hypothesis, the advances on biotechnology-driven recycling processes for metals extraction from e-waste has been analyzed briefly. Thereafter, based on the potential of microbial techniques and research hypothesis, the structural model has been tested for a significance level of 99%, which is supported by the corresponding standardization co-efficient values. A prediction model applied to determine the recycling impact on CirBioeco indicates to re-circulate 51,833 tons of copper and 58 tons of gold by 2030 for the production of virgin metals/raw-materials, while recycling rate of the accumulated e-waste remains to be 20%. This restoration volume of copper and gold through the microbial activities corresponds to mitigate 174 million kg CO2 emissions and 24 million m3 water consumption if compared with the primary production activities. The study potentially opens a new window for environmentally-friendly biotechnological recycling of e-waste under the umbrella concept of CirBioeco.