Investigation on the Beneficiation of Fluorite-ore using a mixture of Oleic acid and Palmitic acid via Froth Flotation

Abstract

Fluorite (fluorspar), an important industrial mineral ore, is one of the major raw materials for the production of hydrofluoric acid. Naturally occurring fluorite ore contains gangue minerals, primarily silica (SiO2) and calcite (CaCO3). The beneficiation of fluorspar is needed to mitigate the severity of operational issues. Several studies on fluorspar beneficiation using the froth floatation technique have been executed, but the process is restricted by the use of minerals acids to remove calcite. In this study, a novel scheme for fluorspar beneficiation was investigated for the floatation of fluorite and depression of calcite and other gangue minerals simultaneously without the use of mineral acids. Moreover, mixtures of saturated and unsaturated fatty acids (oleic acid and palmitic acid) were used instead of mineral acids. Various parameters were investigated, such as the weight percent of the feed-slurry, feed pH, the effect of reagents on the process selectivity, and the effect of feed boiling and dilution on the up-gradation of fluorspar. The adopted methodology with tested reagents resulted a 67 wt. % reduction of CO32- and 75 wt. % reduction of SiO2 in gangue material at a pH 10 for the feed slurry. Fluorspar purity increased from 65-75 wt. % to 95 wt. % after the boiling and dilution steps, respectively.