Evaluation of cyanide and heavy metals removal in liquid effluents from small mining’s gold benefit, by adsorption with activated carbon and hydrogen peroxide in Segovia, Antioquia

Abstract

The small gold mining generates toxic substances discharges, being an environmental problem. The objective was to evaluate the removal of cyanide and heavy metals, in liquid effluents from the gold benefit, by adsorption with activated carbon and hydrogen peroxide. The residues were first treated with carbon to determine the adsorption efficiency with 20, 40, 60 g of carbon / L of solution at times of 4, 8, 12 hours. Then hydrogen peroxide (1.0, 1.5, 2.0 liters of peroxide / Kg CN in solution, was added over 4 hours). The response variables were concentrations of cyanide, lead, zinc, iron. The best treatment with carbon was 60 g of carbon / L of solution and 12 hours of contact and for the process with hydrogen peroxide: 2 liters of H2O2 / Kg of CN in solution, during 4 hours. A flow chart and tables for the implementation of the process were designed.

Keywords

• gold mining
• heavy metals removal
• cyanide degradation
• heavy metals precipitation
• environmental pollution