Study on Chlorination Decomposition Process of Bastnaesite Concentrate with Anhydrous Magnesium Chloride

In this paper, magnesium chloride dehydration and chlorination of Sichuan Mianning 60%-grade fluorocarboncerium ore(57.78% fluorite carboncerite, 33.86% fluorite calcerite) was used. The effects of roasting temperature, roasting time, and ore-salt ratio on the decomposition rate of fluorocarbonyl cerium ore were studied. The thermogravimetric(TG)-differential thermal analysis (DSC), X-ray diffraction (XRD) and scanning electron microscopy (SEM)-energy spectrum analysis (EDS) were used to study the reaction mechanism of the chlorination and decomposition of bastnaesite with anhydrous magnesium chloride. The optimal process parameters for chlorination decomposition have been determined: The roasting temperature is 550 ℃, the roasting time is 90 minutes, and the ore-salt ratio is 1∶0.25. Under these conditions, the decomposition rate of fluorocerium ore concentrate can reach 97.23%, and the oxidation rate of cerium is only 50.64%. Chlorination decomposition process of bastnaesite concentrate with Anhydrous Magnesium Chloride can shorten roasting time and reduce energy consumption. The amount of reducing agent can be reduce under the hydrochloric acid leaching process of roasted ore. This process provides a new idea for decomposing bastnaesite.