Copper is among the most abundant metals on earth and is widely used in various fields owing to its excellent properties. Considering the current trends, the demand and use of copper is expected to escalate in the future. However, to meet this target, high-quality copper resources are highly desired. As such, scientists have been looking for alternatives and have identified recovery of copper as well as efficient utilization of copper oxide ores as a promising solution.
Presently, several methods including floatation, leaching, and metallurgical processes have been developed to enable effective treatment of copper oxide ores. For instance, floatation technique works based on the difference in the physicochemical properties to aid concentration of the desired minerals. However, regardless of the significant improvements, recycling the ore using these methods have remained a challenge due to the high proportion of combined copper oxide. This has consequently imparted negatively on the efficient and economical utilization of copper and related resources and therefore, development of alternative methods is inevitable.
To this note, a group of researchers at Kunming University of Science and Technology from State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization developed a new technique for recycling complex copper oxide. Fundamentally, the method was based on a combination of floatation and metallurgical processes to accomplish the recycling process. They purposed to significantly enhance the recovery rate of copper oxide from the constituent compositions, which would, in turn, pave way for efficient utilization of copper resources and energy saving. Their work is currently published in the research journal, JOM.
In brief, the authors commenced their research work by cross-examining the characteristics of the ore. Next, they developed a new method for copper recovery based on floatation-high-gradient magnetic separation-leaching. This process enabled obtaining of magnetic separation concentrates. On the other hand, the leaching concentrates and tailings were conducted at 80 °C and 40 °C using 90kg/t and 45kg/t acid leaching respectively. Eventually, they verified the feasibility of the proposed method for efficient copper oxide recovery and energy saving.
The authors observed that the proposed method significantly enhanced copper recovery rate as compared to the conventional traditional methods. For example, by using sodium sulfide and butyl xanthate as a vulcanizing agent and collector respectively, a recovery rate of 32.22% was obtained for a copper grade of 29.37%. Additionally, leaching rates of copper from the magnetic concentrates and tailings were recorded as 28.44% and 26.95% respectively.
In summary, the proposed methods by Kunming University of Science and Technology scientists proved efficient for copper recovery, energy saving, and adaptability. Copper recovery was enhanced up to 87.61%. Generally, the flexibility of the process allows adjustments according to the ore characteristics. Therefore, the study will pave way for enhancing the recovery rates for not only ores with similar characteristics but also those with dissimilar characteristics.
Bai, X., Wen, S., Feng, Q., Liu, J., Lin, Y., & Yao, Z. (2019). A New Technique for Recovering Copper from Complex Copper Oxide Ore by Flotation and Metallurgical Processing. JOM, 71(2), 784-790.Go To JOM