Selective Recovery of Precious Metals through Photocatalysis

Abstract Precious metals such as gold and platinum are valued materials for a variety of important applications, but their scarcity poses a risk of supply interruption. However, the dissolution and recovery of precious metals using the current methods are limited by associated serious environmental pollution and high energy consumption. Here, we show a photocatalytic process that allows one to selective retrieve 7 kinds of precious metal elements (Ag, Au, Pd, Pt, Ru, Rh and Ir) (with dissolution efficiency of 99%) from waste circuit boards, ternary automotive catalysts and even ores. Precious metals is recovered with high purity (≥98%) through a simple reductive method. The whole process only needs light and catalyst without strong acid, strong base and highly toxic cyanide. It has an environmentally friendly, scalable and efficient way, in which the catalyst has been recycled more than 100 times under normal temperature and pressure without performance degradation. It has successfully realized the scale of dissolution from grams to kilograms, and it is expected to realize large-scale recovery of precious metals in industrial application. This general approach provides an unprecedent technology for recycling resources on earth.