Effect of amino acids on the extraction of copper from sub-conditional raw materials

The decrease in the quality of mineral raw materials processed by industry, as well as the increase in requirements for environmental protection, necessitate the development of new directions in the technology of their processing. Biogeotechnology refers to one of the modern areas of scientific and technological progress in the field of processing mineral raw materials. Biologically active additives are increasingly used along with the use of microorganisms in the extraction processes for non-ferrous and precious metals, in particular amino acids which are an integral part of the culture liquid of microorganisms. The processes of sulfuric acid leaching of copper from low-grade ore in the presence of amino acids of different structures and their effect on copper electrolysis were studied. Low-grade ore from one of the Kazakhstan deposits was used as the starting raw material. The copper content in the ore is 0.39%. The diffusion nature of the restrictions was established during the study of the kinetics of the process of sulfuric acid leaching of copper, and the rate constants and value of the effective activation energy were calculated, which amounted to 1.817 kJ/mol. The effect of amino acids with different structures on the leaching process was studied. The positive effect was increased in the glycine - leucine - cysteine - histidine - asparagine series. Depending on the structure of the amino acid, the degree of copper extraction into the solution increases in the range of 1-15%. The effect of aminoacetic acid as a biologically active additive on the process of electrolysis of copper from poor solutions was studied. It was established that the process is inhibited by the reduction of monovalent copper to the metallic state in the presence of glycine.