화학공학소재연구정보센터
Journal of Industrial and Engineering Chemistry, Vol.116, 217-228, December, 2022
Phase transformation and roasting kinetics of cobalt-rich copper sulfide ore in oxygen atmosphere assisted by sodium sulfate
The recovery rates of copper (99 %) and cobalt (93 %) could be significantly increased by adding sodium sulfate in activated roasting of Cobalt-rich copper sulfide (CRCS). The mechanism and kinetic parameters of CRCS roasting with sodium sulfate addition were not clear. Thus, in this study, the thermal roasting kinetics of carrollite (the predominant cobalt occurrence mineral) in CRCS adding Na2SO4 with an air atmosphere was studied in detail by TG-DTG method. The apparent activation energy (E) and preexponential factor (A) were obtained via Flynn-Wall-Ozawa method (FWO) and Kissinger-Akahira- Sunose method (KAS) methods, where E values were 113.89 kJ∙mol-1 (KAS) and 120.87 kJ∙mol-1 (FWO). The thermodynamic parameters of the roasting process were evaluated. The model function for the carrollite reaction was determined via Malek analysis. The mechanism of sodium sulfate addition in CRCS roasting was studied. Results showed that the addition of sodium sulfate in activated roasting can promote the transformation of carrollite mineral phase. The activation energy value of the oxidation process of carrollite decreases. From the kinetic point of view, the addition of sodium sulfate can promote the activation roasting.