Flotation separation of scheelite and calcite using biopolymer konjac glucomannan: A novel and eco-friendly depressant

This study investigated the effect of konjac glucomannan (KGM) on the flotation separation of calcite and scheelite. Micro-flotation tests showed that the floatability of calcite decreased significantly under the action of 50 mg/L KGM, while the impact on scheelite was negligible, resulting in a recovery difference of 82.53%. Fourier transform infrared spectroscopy (FTIR) and atomic force microscopy (AFM) analyses indicated that KGM was selectively adsorbed on the calcite surface. The zeta potential and UV-visible absorption spectroscopy test results revealed that KGM prevented the adsorption of sodium oleate on the calcite surface. X-ray photoelectron spectroscopy (XPS) analysis further confirmed that KGM achieved chemical adsorption on the calcite surface and formed Ca(OH)2. The density functional theory (DFT) simulation results were consistent with the flotation tests and measurement analyses, demonstrating that KGM had stronger adsorption performance on the calcite surface. This study provides a pathway for more sustainable and cost-effective mineral processing by utilizing the unique properties of biopolymers such as KGM to separate valuable minerals from gangue minerals.