Effect of particle size of modified activated carbon on adsorption of gold-thiosulfate complex

It is the most promising non-toxic method for thiosulfate gold leaching to replace cyanide extraction, but the failure of economic and effective recovery of gold-thiosulfate complex in leaching solution hinds the industrial application of this method.In this paper, in order to improve the loading capacity of activated carbon to, modified activated carbon is prepared by high temperature thermal activation method with three kinds of different granular activated carbon as raw materials and melamine as nitrogen source.By static adsorption, particle size and specific surface area, SEM-EDS and XPS, the effects of melamine dosage, modified temperature, thermal activation temperature and time on the adsorption of gold on modified activated carbon and adsorption mechanism are studied in detail.The results show that the activated carbon with the particle size of 0.45-0.90 mm adding 3.75% melamine, modified temperature of 50 ℃, thermal activation temperature of 750 ℃ for 60 min, the prepared activated carbon has the maximum adsorption capacity of 553.35 μg/g for.It is found that the average particle size and large proportion of micropores of 0.45-0.90 mm modified activated carbon is suitable for the adsorption of on activated carbon.What's more, the functional groups of quaternary nitrogen increase the positive electric property on the surface of activated carbon, and the functional groups of oxygen increase the hydrophilicity of activated carbon.These factors together greatly enhance the adsorption of on the modified activated carbon.