Research On Copper Raffinate And Leaching Solution In Copper Hydrometallurgy By Efficient Processing Technology

Copper hydrometallurgy is gaining more and more interests in recent years. However, with decrease in ore grade, now the iron content increases, while the copper decreases. In copper hydrometallurgy system, iron can’t be treated effectively. To solve this question, the technical process which removes iron by phosphate and recovers copper by three-dimensional electrode reactor from copper raffinate is proposed. Copper content of biology leaching solution is lower, which led to low extraction efficiency. To this issue, the separate technique which adopts effective way to remove Fe and enrich Cu is suggested.The processes of copper raffinate as the high iron-low copper solution are studied. The technical process of removing iron by phosphate is proposed. The results show that the optimal conditions are found, including sodium phosphate to be theoretical amount, pH to be1.5, response time to be20min, H2O2to be5times of theory and at ambient temperature. Under this condition, it can obtain the optimal separation efficiency, which removal rates of Fe and Cu are99%and2%, respectively. In the research about the recovery of phosphate anions, the optimal conditions are found, including NaOH to be0.8times of the theoretical amount, response time to be2.5h. The results indicate that the recovery rate is almost100%.This process has lots of advantages, including easy operation, short cycle, low energy consumption, being environment-friendly and so on. Therefore, it is to be significant in utilization of high iron-low copper solution.A dilute copper wastewater after the treatment is treated by using a three-dimensional electrode reactor. For electrolyses under the conditions of graphitized coke as particle electrode, circulating electrolyte, cell voltage of3.5V, sulfuric acid concentration of85g·L-1, time of60min, temperature of25℃, coke quantity of300g·L-1and coke size of5-8mm, the copper recovery rate and current efficiency are about99%and93%, respectively. Copper concentration in the solution after the treatment is less than2mg·L-1.Removing iron from biology leaching solution by neutralization is researched. The results show that the optimal conditions are found, including pH to be3.5, T to be50℃, response time to be60min. Under this condition, it can obtain the optimal separation efficiency, which removal rates of Fe and Cu are98.23%and1.9%, respectively. Cu and Fe concentration in the solution after the treatment are0.203g-L-1and0.012g·L-1, respectively.Enriching copper from biology leaching solution after the treatment by NF membrane technology is researched. The results show that the optimal conditions are found, including pressure to be15bar, T to be30℃, flux to be14L/min, concentrates to be3.7times. Under this condition, the copper rejection is over95%. The concentrations of Cu and Fe in concentrated solution are0.764g-L-1and43.2mg-L-1, respectively. While they are9.86mg·L-1and Og·L-1in permeate, respectively.