Abstract: To address the challenge of utilizing a high-potassium,medium-low-grade phosphate ore from Hubei,this study initiated with a systematic process mineralogical investigation to elucidate its mineral composition and dissemination character istics.The results indicated that the valuable mineral is primarily fluorapatite,with gangue minerals dominated by K-feldspar, quartz,and a minor amount of dolomite.These gangue minerals are intricately disseminated and closely associated with fluorap atite.Furthermore,the ore contains a high proportion of fine particles smaller than 38 μm.Based on these findings,a combined beneficiation process of "pre-removal of iron,reverse flotation for desiliconization,and reverse flotation for magnesium removal" was developed,employing butyl xanthate,ether-amine collector H-1,phosphoric acid,and fatty acid collector GW-01 as key re agents.Closed-circuit tests yielded a concentrate with a P2 O5 grade of 31.96% and a recovery of 86.78%.The contents of K2 O,SiO2 ,MgO,and sesquioxide (Al2 O3 +Fe2 O3 ) in the concentrate were reduced to 0.99%,8.98%,0.54%,and 2.06%, respectively.This process successfully demonstrates the efficient recovery and utilization of this refractory high-potassium collo phane ore.

Key words: collophane,high-potassium phosphate ore,process mineralogy,reverse flotation,desiliconization