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New development and technological innovations make electrical and electronic equipment (EEE) more functional by using an increasing number of metals, particularly the critical metals (e.g. rare and precious metals) with specialized properties. As millions of people in emerging economies adopt a modern lifestyle, the demand for critical metals is soaring. However, the increasing demand causes the crisis of their supply because of their simple deficiency in the Earth's crust or geopolitical constraints which might create political issues for their supply. This paper focuses on the sustainable supply of typical critical metals (indium, rare earth elements (REEs), lithium, cobalt and precious metals) through recycling waste electrical and electronic equipment (WEEE). To illuminate this issue, the production, consumption, expected future demand, current recycling situation of critical metals, WEEE management and their recycling have been reviewed. We find that the demand of indium, REEs, lithium and cobalt in EEE will continuously increasing, while precious metals are decreasing because of new substitutions with less or even without precious metals. Although the generation of WEEE in 2014 was about 41.9 million tons (Mt), just about 15% (6.5 Mt) was treated environmentally. The inefficient collection of WEEE is the main obstacle to relieving the supply risk of critical metals. Furthermore, due to the widespread use in low concentrations, such as indium, their recycling is not just technological problem, but economic feasibility is. Finally, relevant recommendations are point out to address these issues., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Waste electrical and electronic equipment (WEEE) has been one of the fastest growing waste streams worldwide. Effective and efficient management and treatment of WEEE has become a global problem. As one of the world's largest electronic products manufacturing and consumption countries, China plays a key role in the material life cycle of electrical and electronic equipment. Over the past 20 years, China has made a great effort to improve WEEE recycling. Centered on the legal, recycling and technical systems, this paper reviews the progresses of WEEE recycling in China. An integrated recycling system is proposed to realize WEEE high recycling rate for future WEEE recycling., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Platinum group metals (PGMs) are indispensable for the automobile, petrochemical, energy, and national defense industries. However, the mineral resources of PGMs are extremely scarce in China, and the contradiction is prominent between the supply and demand of the resources. Therefore, recycling PGMs becomes an important measure to ensure the safe supply of PGMs and support the high-quality development of related industries. This study analyzes the supply and application of PGMs, clarifies the supply and demand trend of the PGMs market, and sorts out the recycling technologies of PGMs. The hydrometallurgical process includes cyanidation as well as hydrogen chloride combined oxidant method. The pyrometallurgical process includes capture by lead,copper, matte, and iron. The research and application of the pyro-hydro-metallurgical recycling process for PGMs are elaborated from the aspects of the roasting-leaching, iron capture-acid leaching, and low-temperature iron capture-electrolysis-centrifugal extraction processes. The low-temperature iron capture-electrolysis-centrifugal extraction process follows the research idea of low-temperatureiron capture. Through the design of slags with a low melting point, the iron capture temperature is reduced from beyond 1800 ℃ to around 1400 ℃. The enriched Fe-PGM alloy is further enriched by electrolysis, and Pd, Pt, and Rh are successively obtained through centrifugal extraction and purification, realizing the short-process separation and purification of PGMs. This process has the advantages of green, high efficiency, and low cost. Focusing on the high-quality development of the PGM recycling industry, we propose the following suggestions: (1) conducting basic research and technical breakthroughs centering the entire process of PGM enrichment, separation and purification, as well as pollution prevention and control; (2) accelerating the construction of a full-chain standards system for PGM recycling and a green and low-carbon industrial ecological environment; and (3) improving the Internet Plus capabilities through the entire business links to realize the intellectualization of the whole recycling-processing-reuse process.

[Display omitted] • The advances in recycling LiFePO 4 have been reviewed. • Direct regeneration technologies of LiFePO 4 are discussed. • Hydrometallurgical leaching methods of LiFePO 4 are outlined. • Challenges and future directions for LiFePO 4 recycling are proposed. LiFePO 4 batteries have become one of the most promising batteries due to their excellent electrochemical performances, long life cycle, safety, and abundant mineral resources. As a result, the demand and scraped LiFePO 4 batteries increased dramatically in recent years. The recycling of waste LiFePO 4 batteries has raised great attention with the consideration of environmental issues and resources conservation. To date, there are massive literatures on the recycling of LiFePO 4 batteries aiming at providing an effective, economic and environmentally sustainable approach. Consequently, this review sorts out and analyzes the current advances in recycling LiFePO 4 from spent lithium batteries with the purpose of promoting the improvement of their recycling. Based on the damage degree of LiFePO 4 materials, direction regeneration and hydrometallurgical leaching are the main recycling processes. The direction regeneration of LiFePO 4 routes including high temperature solid regeneration, hydro/solvent thermal regeneration and electrochemical lithiation are discussed in detail. Inorganic or organic acid leaching, mechanically activated leaching and other leaching methods are reviewed as well. Finally, by comparing the various recycling technologies, the challenges are outlines and future directions for promoting the recycling effectiveness are proposed. [ABSTRACT FROM AUTHOR]