Abstracto

Dissolution kinetics of refractory gold concentrate by ozone in ferric sulfate solutions

Li Qing Cui, Li Deng Xin, Chen Quan Yuan

This paper presents a study for leaching kinetics of refractory gold concentrate (RGC) with ozone in ferric sulfate solution. The influence of various parameters such as ozone concentration, temperature, reaction time, solid / liquid ratio and particle size on the iron extraction rate was investigated. The shrinking core model was suggested to describe the leaching process of RGC analyzing the kinetic data. The activation energy for the leaching processwas found to be 11.47 kJ/mol in the temperature range of 70-100 0C. Consequently, the rate of the reaction based on a reaction-controlled process could be expressed as 1- (1-á) 2/3 =22303.97e-11.47/RT t. The dissolution of RGC with ozone and ferric sulfate solutionwas found to be controlled by diffusion-controlled process.