In Chinese myth, “Xi Rang” is a kind of soil that never stops growing. Now, A new extractive precipitant that is similar to “Xi Rang” is developed. What the magic is it compounds with rare earths and forms solid extraction complex, which can repeatly extract and recycled. It raise the efficiency of rare earth separation and enrichment, which avoid large wastes from traditional technology.
As nonrenewable scarce strategic resources, rare earths are called ” super industrial MSG”. At present, clear production technology of rare earths with low cost is worldwide problem, which is industry commanding height that every countries strive to overcome. The scientific research achivevement is developed by Sun XiaoQi from XiaMen Institute of Rare Earth Materials, HaiXi Research Institute, Chinese Academy of Science. It is published on international journal <Hydrometallurgy>, which makes our rare earth separation technology leading the global.
From cellphone, camera to precision-guided missile, satellite rocket, rare earths play roles in every industries. Rare earths include light rare earths and heavy rare earths. Specially Ion type rare earth ores exist in Southern China, which takes more than 70% heavey rare earths of global reserves. They are scarce and the substitutions are rare, which get wide applications in spaceflight, military, national defense, synthesis of new materials and other edge technologies.
However China is weak in developing previously although with largest reserves. In 1960s, Core technology of rare earth separation was mastered by a few countries all the time. China had to purchase processed rare earths from overseas with high cost, altough owning huge rare earth resources.
After old scientists as Xu Guangxian academician’s hard work for several decades, Rare earth seperation chemistry and engineering research made great headway in China. China is in leading position of rare earth excavating, smelting, separating and purifying and establish integraetd industrial chain of rare earth resources utilization. China already become the country having world’s largest reserves, maximum output and largest exports. However the traditional rare earth separation and purification technology also brought some problems as low resource utilization rate and environment pollution.
According to measuring, average resource utilization rate of China ion type rare earth ores is lower than 25%. Each separated ion adsorption type rare earth ores consume 8-10tons hydrochloric acid, 6-8ton caustic soda liquid or 1-1.2tons liquid ammonia and so on.
Actually, China traditional rare earth separation system is origin from overseas, which operate for over decades. Enterprises are very difficult to adjust the process parameters to improve. How to change rare earth raw material structure? And make the whole rare earth extraction process don’t turns out wastes? They are the questions China rare earth industry explore and think over all the time.
To change the situation, it should start from the fountainhead. Sun XiaoQi team focus on national aim, based on fundamental researches and explore new extraction systems, which drive the development of clear high effiencey rare earth extraction technology, improvement of rare earth sources and sustainable development.
In rare earth hydrometallurgical industry, the main purpose of separation process based on extraction agent is purifying and gathering, so extraction agent is the key fact affecting extraction technology results.
In China rare earth production industry, solvent extraction method andchemical precipitation method are the two main speration techologies, but there are still many shortages, for example solvent extraction method need vast volatile organic solvents that cause safety and environment problem, ammonium bicarbonate and industrial oxalic acid precipitator couldn’t be recycled that turns out waste water and pollute environment.
The key to clear high efficiency rar earth separation technology is to design, prepare and find out low cost and high efficiency extraction-precipitator.” Sun XiaoQi said. It is a relatively complex procedures, which should consider cost, raw material, stability, extraction rate, selectivity, time, extraction volume, anti-extraction property, solubility, toxicity and so on.
Therefore Sun XiaoQi term did lots of basic application researches on solution coordination chemistry, extraction agent design, separation material by using world edge technology, which cover key scientific questions for rare earth separation procudures from basic researches to industrialization.