Comparison of Microwave-Assisted and Conventional Leaching for Extraction of Copper from Chalcopyrite Concentrate

Authors: Ayfer Kilicarslan, Kubra Onol, Sercan Basit, Muhlis Nezihi Saridede

Abstract:

Chalcopyrite (CuFeS2) is the most common primary mineral used for the commercial production of copper. The low dissolution efficiency of chalcopyrite in sulfate media has prevented an efficient industrial leaching of this mineral in sulfate media. Ferric ions, bacteria, oxygen and other oxidants have been used as oxidizing agents in the leaching of chalcopyrite in sulfate and chloride media under atmospheric or pressure leaching conditions. Two leaching methods were studied to evaluate chalcopyrite (CuFeS2) dissolution in acid media. First, the conventional oxidative acid leaching method was carried out using sulfuric acid (H2SO4) and potassium dichromate (K2Cr2O7) as oxidant at atmospheric pressure. Second, microwave-assisted acid leaching was performed using the microwave accelerated reaction system (MARS) for same reaction media. Parameters affecting the copper extraction such as leaching time, leaching temperature, concentration of H2SO4 and concentration of K2Cr2O7 were investigated. The results of conventional acid leaching experiments were compared to the microwave leaching method. It was found that the copper extraction obtained under high temperature and high concentrations of oxidant with microwave leaching is higher than those obtained conventionally. 81% copper extraction was obtained by the conventional oxidative acid leaching method in 180 min, with the concentration of 0.3 mol/L K2Cr2O7 in 0.5M H2SO4 at 50 ºC, while 93.5% copper extraction was obtained in 60 min with microwave leaching method under same conditions.

Keywords: Extraction, copper, microwave-assisted leaching, chalcopyrite, potassium dichromate.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1108148

References:

[1] S. Wang, “Copper Leaching from Chalcopyrite Concentrates.” JOM, Vol. 7, 2005, pp 48-51.
[2] C. K. Gupta, T. K. Mukherjee, “Hydrometallurgy in Extraction Processes,” CRC Press. Vol. 1, 1964.
[3] H. R. Watling, “Chalcopyrite Hydrometallurgy at Atmospheric Pressure: 1. Review of Acidic Sulfate, Sulfate–Chloride and Sulfate–Nitrate Process Options,” Hydrometallurgy, vol. 140, 2013, pp 163-180.
[4] D. Dreisinger, “Copper Leaching from Primary Sulfides: Options for Biological and Chemical Extraction of Copper,” Hydrometallurgy, Vol. 83, 2006, pp 10-20.
[5] C. Klauber, “A Critical Review of the Surface Chemistry of Acidic Ferric Sulphate Dissolution of Chalcopyrite with Regards to Hindered Dissolution,” International Journal of Mineral Processing, Vol. 86, 2008, pp 1-17.
[6] E. M. Córdoba, J. A. Muñoz, M. L. Blázquez, F. González, A. Ballester, “Leaching of Chalcopyrite with Ferric Ion. Part I: General Aspects, ” Hydrometallurgy, vol 93,2008, pp 81-87.
[7] S. Aydogan, G. Ucar, M. Canbazoglu, “Dissolution Kinetics of Chalcopyrite in Acidic Potassium Dichromate Solution” Hydrometallurgy, vol 81, 2006, pp 45-51.
[8] K. Onol, M.N Saridede, “Investigation on Microwave Heating for Direct Leaching of Chalcopyrite Ores and Concentrates,” International Journal of Mineral Metallurgy and Material, Vol. 20, 2013, pp 228-233.
[9] X. Zhai, Q. Wu, Y. Fu, L. Ma, C. Fan, N. Li, “Leaching of Nickel Laterite Ore Assisted by Microwave Technique” Transactions of Nonferrous Metals Society of China, Vol. 20, 2010, pp. 77-81.
[10] T. Suoranta, O. Zugazua, M. Niemelä, P. Perämäki, “Recovery of Palladium, Platinum, Rhodium and Ruthenium from Catalyst Materials Using Microwave-Assisted Leaching and Cloud Point Extraction,” Hydrometallurgy, Vol. 154, 2015, pp. 56-62.
[11] G. Chen, J. Chen, J. Peng, R. Wang, “Green Evaluation of Microwave- Assisted Leaching Process of High Titanium Slag on Life Cycle Assessment”, Transactions of Nonferrous Metals Society of China, Vol. 20, 2010, pp. 198-204.
[12] D.A. Jones, T.P. Lelyveld, S.D. Mavrofidis, S.W. Kingman, , N.J. Miles, “Microwave Heating Applications in Environmental Engineering-A Review”, Resources, Conservation and Recycling, Vol. 34, 2002, pp.75- 90.
[13] M. Al-Harahsheh, S.W. Kingman, “Microwave-Assisted Leaching-A Review, Hydrometallurgy, Vol. 73, 2004, 189 -203.
[14] K.E. Haque, “Microwave Energy for Mineral Treatment Processes-A Brief Review”, International Journal of Mineral Processing, Vol. 57, 1999, pp. 1-24.
[15] M. Al-Harahsheh, S. Kingman, “The Influence of Microwaves on the Leaching Kinetics of Chalcopyrite”, Minerals Engineering, Vol. 18, 2005 pp. 1259-1268.