Mineralogical Characteristics of Pegmatite Tailings and Beneficiation Assessment of Pollucite in Recovering Cesium

Abstract

The technological mineralogical characteristics of cesium-containing minerals in tailings were examined by means of chemical analysis, the energy spectrum analysis method, and MLA (mineral liberation analyzer) to determine the element content, phase analysis, associated mineral components, degree of liberation, particle size, etc. The results showed that the samples mainly contained spodumene, quartz, feldspar, mica, and other minerals. Pollucite was the main cesium-containing mineral in the sample, which had a cesium oxide content that was as high as 34.58%. The mineral content of pollucite in the sample was relatively low—only 1.23%. The pollucite monomer content and the amount of rich intergrowth was 85.25%, and the metal distribution of cesium in the +0.074 mm sample was as high as 87.06%. Spodumene was the main mineral associated with pollucite. The beneficiation evaluation of this tailing sample was conducted using a combined process that integrated desliming, magnetic separation, and froth flotation, and a pollucite concentrate containing 4.45% Cs2O was obtained with a 63.71 recovery rate. This indicates that little pollucite was removed by means of desliming and magnetic separation before froth flotation recovery, but during the froth flotation stage in spodumene and feldspar, a large pollucite loss was observed. Therefore, to improve pollucite recovery, a pollucite-specific adsorption reagent should be synthesized.