Dissolution kinetics of colemanite in potassium dihydrogen phosphate solution (KH2PO4)

Abstract

Colemanite is rich in boron, and it is a common raw material used to produce boron components. The first step in this process is the dissolution of colemanite using different leaching solutions. The main aim of this study was to investigate the dissolution kinetics of colemanite in potassium dihydrogen phosphate (KH2PO4) solution. The reaction temperature (T), the KH2PO4 concentration (C), the stirring speed (W), the solid-to-liquid ratio (S/L) and particle size (D) of the colemanite were selected as parameters affecting the rate of its dissolution. The Statistica software package was used to correlate the experimental results. The findings of the study showed that the dissolution rate of colemanite in KH2PO4 solution increased with increasing reaction temperature and KH2PO4 concentration, while an increase in particle size and solid-to-liquid ratio caused a decrease. Heterogeneous and homogeneous reaction models were tried in order to derive a proper kinetic model for colemanite dissolution. According to the results, it was determined that the colemanite dissolution process is controlled by a chemical reaction model. The activation energy value (41.88 kJ mol−1) also verified this conclusion.