High purity magnesium oxide

The copper ore used for mining is mainly surface oxidized copper cobalt polymetallic ore, therefore, copper mining mostly adopts wet process. The wet production process of copper generally involves ore leaching (heap leaching or stirring leaching) - extraction - electrowinning. During copper leaching, cobalt is usually leached with sulfur dioxide or sodium sulfite as reducing agents. Copper and cobalt are extracted from sulfuric acid solutions containing copper and cobalt and electrodeposited to produce cathode copper. Most cobalt products produced by enterprises are crude cobalt compounds made by simply removing impurities in the above process. The most common crude cobalt compound is cobalt carbonate produced by precipitation of cobalt with sodium carbonate.

However, the cobalt content in crude cobalt carbonate is relatively low, mostly around 25%, which increases transportation and other costs. The cobalt solution after sodium carbonate precipitation contains a large amount of difficult to treat sodium salts, so direct discharge will cause environmental pollution. Long term recycling in the system will cause a large amount of sodium ion enrichment in the solution, seriously affecting copper production. With the gradual tightening of environmental protection policies, many enterprises have begun to research more economical and environmentally friendly cobalt production processes. The magnesium oxide precipitation cobalt process is an effective method to solve this problem. Practical applications have shown that by neutralizing and removing impurities from the cobalt containing copper extraction residue, magnesium oxide has an impact on cobalt precipitation. The final pH value is 8.0, and using magnesium oxide slurry to deposit cobalt has the best effect. The grade of cobalt hydroxide is higher than 36%, the cobalt recovery rate is higher than 99%, and the utilization rate of magnesium oxide is 91%.

The recovery of cobalt from cobalt sulfate solution is usually achieved by adding magnesium oxide slurry to produce cobalt hydroxide products. The stability of magnesium oxide slurry concentration is crucial for the product quality of cobalt industrial production. The higher the concentration of magnesium oxide slurry, the higher the impurity magnesium content in cobalt products, which affects product quality. The lower the concentration of magnesium oxide slurry, the lower the recovery rate of cobalt.