I. Overview
Currently, the ore used in mining in the Democratic Republic of Congo is mainly copper-cobalt polymetallic ore oxidized on the surface. Therefore, wet process is generally used to extract cobalt. With the further increase of investment in the Democratic Republic of Congo by domestic and foreign mining and metallurgical enterprises, the output of wet-process cobalt refining has a significant growth trend.
II. Process
1. Conventional hydroxide precipitation process mainly includes two technologies: sodium hydroxide precipitation and magnesium oxide precipitation. Compared with sulfide precipitation technology, hydroxide precipitation technology is simple to produce, with low investment and operating costs. The disadvantage is that the product has high impurities and high water content.
2. The latest lime precipitation nickel and nickel-calcium separation technology has been successfully developed in the laboratory. The lime precipitation cobalt and cobalt-calcium separation technology developed by it has been applied in industrial projects. Both technologies belong to hydroxide precipitation technology. The nickel-cobalt precipitation rate of this technology is about 95%, and the product contains 40% to 50% water.
3. Activated magnesium oxide precipitation technology is used in cobalt refining. The precipitation temperature of this technology is about 60 to 70 ° C, the nickel-cobalt precipitation rate is about 95%, and the product contains 40% to 50% water.
4. In terms of cobalt extraction production technology, Messi Biology uses the self-developed active magnesium oxide cobalt precipitation technology, which avoids the high toxicity and difficult control of hydrogen sulfide nickel-cobalt precipitation technology, solves the problems of high raw material requirements, high cost, and high magnesium content of magnesium oxide cobalt extraction, and successfully develops crystallization precipitation technology, which reduces the water content of the product from 75% to about 50%. This process consumes less production, is simple to operate, and greatly improves production stability.
III. Prospects
China is a country with serious shortage of cobalt resources. With the rapid economic development in recent years, especially the rapid development of the lithium battery industry, the demand for cobalt is increasing. At present, in addition to several companies such as Messi Biology that have cobalt extraction technology, there are still some unscaled magnesium oxide manufacturers for cobalt extraction. Therefore, my country urgently needs to develop and build a large-scale production process and production line for magnesium oxide for cobalt extraction, which is of great significance in reducing the strategy of hydrometallurgical extraction of nickel and cobalt.