Experimental research on biological pre-oxidation and gold leaching by using TCCA for carbon-containing refractory gold ore
A carbon-containing refractory gold concentrate contained Au 15.9 g/t,the mass fraction of Fe,As,S and total C were 23.17%,3.41%,24.7%and 6.06%,respectively.Au was mainly encapsulated by pyrite and arsenopyrite in the form of submicroscopic particles,and the presence of carbon led to"preg-robbing"effect.In this paper,based on the characteristics of gold concentrate,a biological pre-oxidation and TCCA gold leaching experiments were conducted,and the multiple linear regression model was established to analyze the significant influence of various factors on the gold leaching efficiency.The results show that after biological pre-oxidation,sulfur and arsenic decomposition efficiency reach 63.59%and 85.77%,respectively.Raman spectra reveals that there is a decrease in carbon defects within a reduction of gold-adsorbing capability.Furthermore,the multiple linear regression analysis indicates that TCCA,NaCl and temperature significantly affect the gold leaching efficiency with a positive correlation.The optimal conditions for TCCA leaching are as follows:TCCA concentration of 0.22 mol/L,NaCl concentration of 30 g/L,temperature of 45℃,solid mass fraction in slurry of 20%,and reaction time of 3 h,which results in a gold leaching efficiency of 87.49%and yields a final gold concentration in the leaching solution measured at 6.004 mg/L.
carbon-containing refractory gold concentratebiological pre-oxidationRaman spectraTCCA leachingmultiple linear regression model
万方数据
维普
