ACID AND AMMONIA LEACHING OF SECONDARY COPPER SULFIDES
Todor Angelov, Ivanka Valchanova
University of Mining and Geology “St. Ivan Rilski”, 1700 Sofia
Corresponding author: Todor Angelov, E-mail: tangelov419@gmail.bg
ABSTRACT. The study focuses on understanding the efficiency and kinetics of copper recovery from secondary sulphide ores, which are increasingly becoming a significant source of copper. An experimental investigation was undertaken to assess the leaching behaviour of secondary copper sulphides in acid and ammonia media. The test work consisted of ore sample characterisation, including physico-mechanical properties determination, chemical assay, whole rock analysis, mineralogy, and copper distributions, followed by acid consumption tests, agglomeration, and agitation leach tests. Leaching tests were conducted in a lab-scale agitated reactor using 100 g of the ore sample, 0.3 l of leach solution, а stirring rate of 420 rpm and a leach time of up to 200 hours. The effect of the reaction time and oxidant (Fe3+, NO+) concentration on the copper recovery was evaluated. The maximum copper extraction was obtained in the test performed using acid media with the addition of NO+ as an oxidant. Further, a potential hydrometallurgical process option for recovering copper from secondary sulphide sources is proposed.
Key words: copper, leaching, secondary sulphides, oxidant
DOI: https://doi.org/10.58903/dv69110151
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