Chromium, a strategic resource, plays a significantly important role in the national economy.Traditional high-temperature roasting technology suffers from high energy consumption and poor resource utilization as well as discharge of a large amount of chromium-containing residue. Consequently, more efficient and cleaner processes for Cr(III) Oxidation are of great value and highly desirable.

Based upon the liquid phase oxidation technology using sub-molten salt (SMS) medium developed by Prof. ZHANG Yi in the Institute of Process Engineering, Chinese Academy of Sciences (IPE-CAS), and the international research cooperation with Prof. Jan D. Miller in the department of metallurgical engineering, University of Utah, USA,  researchers in the Laboratory of SMS Cleaner Chemical Metallurgy have developed the electrochemical Cr(III) oxidation process in alkaline solution at room temperature, which can be easily optimized by modulating the medium.

This novel oxidation technology has many advantages, such as ambient reaction condition, highly efficient and selective, easily adjusted and no oxidant addictives. These special properties make the electrochemically assisted SMS oxidation a potentially wide applicable new technology for mineral processing industries, achieving comprehensive utilization of resources. This work is supported by National Basic Research Program (also called 973 Program)（2007CB613501）,national 863 program（2009AA064003）and the National Natural Science Foundation of China（51090382）, and research results have recently been published in Electrochimica Acta( 2011, 56, 8311– 8318).

The electrochemical Cr(III) in KOH solution at room temperature (Image by  Wei Jin at IPE)