METHOD FOR COMPREHENSIVELY RECOVERING RARE EARTH AND FLUORINE IN BASTNAESITE TREATMENT PROCESS

摘要

Provided is a method for comprehensively recovering rare earth and fluorine in the bastnaesite treatment process, the method comprising: oxidizing and roasting the bastnaesite, using hydrochloric acid to leach the roasted mixture, adding a roasting additive to the bastnaesite in the roasting process and/or adding a catalytic leaching additive to the mixture in the hydrochloric acid leaching process, so as to obtain a rare earth chloride solution with little cerium and a fluorine-containing cerium-rich residue, and then separating and recovering rare earth fluoride from the fluorine-containing cerium-rich residue. The method of the present invention greatly reduces the consumption of chemical raw materials, the pollution to the environment during use, and the production cost. The method of the present invention reduces the processing steps such as multiple solid-liquid separations and the like, thus simplifying the process, lowering operation intensity, reducing rare earth loss, and improving rare earth recovery rate, especially the hydrochloric acid leaching recovery rate of high-valence non-cerium rare earth. Moreover, the method of the present invention discharges no fluorine during the whole process, and has the characteristics of low consumption and high efficiency.