Estudio de métodos químicos de remoción de cianuro presente en residuos de cianuración provenientes del proceso de extracción de oro de veta en el departamento de Nariño

Abstract

ABSTRACT

This research focused on laboratory-scale neutralization of cyanide wastes from
the Nueva Esparta mine in the municipality of Los Andes, Sotomayor (Nariño) with three commercial type neutralizers in different weight ratios (neutralizer grams / CN-free/total to be neutralized): hydrogen peroxide H2O2 2/1, 5/1 and 8/1, sodium hypochlorite NaOCl 7/1, 12/1 and 17/1 and ferrous sulfate FeSO4 6/1, 12/1 and 18/1. Residual sands were treated as follows: washing with water, neutralization of the washing water and circulation of the same water for a new washing process, this with the purpose of minimizing the quantity of water used. After the statistic analysis and taking into account technical, economical and environmental considerations, it was found that the best treatments for removing free and total cyanide are respectively the relations 2/1 and5/1 from H2O2. A physical-chemical characterization of the water source affected by the activity on the poor cyanide solution and solutions lixiviated in the laboratory of the mine under study was performed. In the evaluation of the metals Fe, Cu, Ni, Zn, Mn and Pbit was observed that after the neutralization with con H2O2, the analyzed metals diminished their concentration. There was an increase in the majority With NaOCl woth a minimum removal of lead and manganese. With FeSO4 there was removal for the majority but lead and manganese increased.

Keywords

cyanide

removal

cyanideresidual sand

gold mining

References

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a. Universidad de Caldas, Departamento de Química. Manizales, Colombia.
b. Universidad de Nariño, Departamento de Química. San Juan de Pasto, Colombia.
c. Empresa Metropolitana de Aseo EMAS S.A. E.S.P. San Juan de Pasto, Colombia.