A New Method for Colemanite Waste Processing

Abstract

In this study, two extraction methods were used sequentially. In the first stage, colemanite process waste was subjected to scrubbing and decantation, and colemanite concentrate was obtained. In the second stage, leaching and filtration processes were carried out on the colemanite concentrate, and pure boric acid was obtained. Colemanite process waste (CPW) contains colemanite, calcite, quartz and others minerals. The boron oxide percentage of CPW was increased by the scrubbing method. Thus, impurities of the CPW were decreased. Scrubbed CPW is referred to as colemanite concentrate (CC). Boric acid extraction was investigated by the leaching of the colemanite concentrate in sulfuric acid solutions. The characterization of colemanite concentrate was determined by X-ray diffraction (XRD) analysis and X-ray fluorescence (XRF) analysis. The leaching parameters in this study were solid/liquid ratio, stirring speed, acid concentration, and reaction temperature. It was observed that the dissolution efficiency increased with increasing reaction temperature and with decreasing solid/liquid ratio and acid concentration. CPW is a problem for the environment; however, in this study, this CPW was converted into a valuable product (boric acid).