Process Mineralogy and Acid Leaching Enrichment of P₂O₅ of the Rare Earth Phosphate Ore in Zhijin, Guizhou Province

ObjectiveIn order to study the technological properties of medium and low-grade phosphate rocks in Xinhua Phosphate Rock Area of Zhijin, Guizhou, Methodthe main mineral components, trace elements and rare earth elements of the ore were studied by X-ray fluorescence spectrometry (XRF), X-ray diffraction pattern analysis (XRD) and microscopic observation. ResultThe chemical composition of phosphate rocks in the study area is mainly SiO₂, followed by P₂O₅, CaO, Al₂O₃, Fe₂O₃ and K₂O. The main ore layer rich in phosphorus and rare earth is banded phosphate rocks. From top to bottom, it is divided into weathered, semi-weathered and primary phosphate rocks. From top to bottom, the content of P₂O₅ and ΣREO is from high to low. The P₂O₅ grade of Majiaqiao ores is 16.76%, the P₂O₅ grade of Damachang is 16.33%, the P₂O₅ grade of Gezhongwu is 17.69%, and the P₂O₅ grade of Yakou is 15.48%, which is the generally low-grade phosphate rock. The ratios of V/Cr and Sr/Ba indicate that the phosphate rock series in Zhijin Area are mostly in oxidizing environment-weak oxidizing environment. Rare earth elements belong to light rare earth enrichment and heavy rare earth relative loss types. The content of ΣREO in the deposit is 661.17 ～ 1 934.16 g/t. The experiment of acid leaching and enrichment of P₂O₅ with acetic acid shows that acetic acid has the best enrichment effect on JD-A, followed by GL-1 and GL-T. The P₂O₅ of JD-A increased from 19.72% to 33.78%. The experimental results of acid leaching and enrichment of P₂O₅ in GL-T samples from citric acid, lactic acid and acetic acid showed that the three organic acids as leaching agents increased the grade of P₂O₅ in GL-T from 15.47% to 27.36%, 28.88%, 23.20%, respectively. ConclusionThe beneficiation process is the comprehensive utilization of medium and low-grade phosphate rocks in Xinhua Phosphate Mine Area, Zhijin, Guizhou.