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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.

Multishell Y2 O3 :Yb(3+) /Er(3+) hollow spheres with uniform morphologies and controllable inner structures are prepared successfully by using a glucose-template hydrothermal process followed by temperature-programmed calcination. Much enhanced upconverted photoluminescence of these Y2 O3 :Yb(3+) /Er(3+) are observed, which are due to the multiple reflections and the enhanced light-harvesting efficiency of the NIR light resulting from the special features of the multishell structures., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)