Department of Botany, College of Basic Science and Humanities, Odisha University of Agriculture and Technology, Bhubaneswar, 751003, Odisha, India.
Mongia Green Foundation, Kolkata, 700091, India.
Appl Biochem Biotechnol. 2023 Dec;195(12):7859-7888. doi: 10.1007/s12010-023-04440-x. Epub 2023 Mar 29.
Pollution by end-of-life electronics is a rapid ever-increasing threat and is a universal concern with production of million metric tons of these wastes per annum. Electronic wastes (E-waste) are rejected electric or electronic equipment which have no other applications. The aggrandized unproper land filling of E-waste may generate hazardous effects on living organisms and ecosystem. At present, millions of tons of E-waste await the advancement of more efficient and worthwhile recycling techniques. Recovery of base and critical elements from electronic scraps will not only reduce the mining of these elements from natural resources but also reduces the contamination caused by the hazardous chemicals (mostly organic micropollutants) released from these wastes when unproperly disposed of. Bioleaching is reported to be the most eco-friendly process for metal recycling from spent electronic goods. A detailed investigation of microbial biodiversity and a molecular understanding of the metabolic pathways of bioleaching microorganisms will play a vital function in extraction of valuable minerals from the end-of-life scraps. Bioleaching technique as an economic and green technology costs around 7 USD per kg for effective reusing of E-waste as compared to other physical and chemical techniques. This review provides a summary of worldwide scenario of electronic pollutants; generation, composition and hazardous components of electronic waste; recycling of valuable elements through bioleaching; mechanism of bioleaching; microorganisms involved in base and critical element recovery from E-waste; commercial bioleaching operations; and upcoming aspects of this eco-friendly technique.
电子废物是一个快速增长的威胁，每年产生数百万吨的电子废物，这是一个普遍关注的问题。电子废物（E-waste）是指已被淘汰的电子或电气设备，已无其他用途。电子废物的大量不当土地填埋可能对生物体和生态系统产生有害影响。目前，数百万吨的电子废物等待着更有效和有价值的回收技术的发展。从电子废料中回收基础和关键元素，不仅可以减少从自然资源中开采这些元素，还可以减少由于这些废物在不当处理时释放的危险化学品（主要是有机微量污染物）造成的污染。生物浸出被认为是从报废电子产品中回收金属的最环保工艺。详细调查微生物生物多样性和生物浸出微生物代谢途径的分子理解，将在从报废品中提取有价值的矿物质方面发挥重要作用。与其他物理和化学技术相比，生物浸出技术作为一种经济和绿色技术，其有效再利用电子废物的成本约为每公斤 7 美元。本文综述了全球电子污染物的状况；电子废物的产生、组成和危险成分；通过生物浸出回收有价元素；生物浸出的机理；从电子废物中回收基础和关键元素的微生物；商业生物浸出作业；以及这种环保技术的未来发展方向。
