Experimental Study on Beneficiation of a Low-Grade Rubidium Polymetallic Ore in Inner Mongolia
The main valuable elements of a rubidium polymetallic ore in Inner Mongolia are rubidium,tantalum and niobium.The Rb2O grade is 0.11%and the content of(Ta,Nb)O5 is 222.9 g/t.Rubidium mainly exists in mica and potassium feldspar in the form of isomorphism,and a small amount exists in albite.Tantalum-niobium minerals are mainly pyrochlore.In order to recover rubidium,tantalum and niobium resources,beneficiation experiments were carried out on the basis of process mineralogy of raw ore.The process flow combining high-intensity magnetic separation with gravity separation recovery of tantalum,niobium-neutral flotation of rubidium-containing mica-fluorine,and free acid flotation of rubidium-containing feldspar was adopted.The pH value of the pulp was adjusted by sulfuric acid.The CK-Y1+DDA combination was used to collect the flotation mica,and the SDS+DDA combination was used to collect the flotation feldspar.Tantalum-niobium concentrate with yield of 0.17%,(Ta,Nb)Os grade of 4.33%and(Ta,Nb)Os recovery of 33.22%,as well as comprehensive rubidium concentrate with yield of 70.26%,Rb2O grade of 0.134%and Rb2O recovery of 87.49%were obtained in the whole process closed-circuit test.The grade of Rb2 O in the tailings was 0.045%,which realized the full recovery of rubidium resources in the ore and the effective recovery of associated tantalum-niobium resources.