Camphor leaf extract as neoteric and environmentally friendly depressant in flotation separation of scheelite and calcite
(1. School of Minerals Processing and Bioengineering, Central South University, Changsha 410083, China;
2. Key Laboratory of Hunan Province for Clean and Efficient Utilization of Strategic Calcium-containing Mineral Resources, Central South University, Changsha 410083, China)
2. Key Laboratory of Hunan Province for Clean and Efficient Utilization of Strategic Calcium-containing Mineral Resources, Central South University, Changsha 410083, China)
Abstract: Camphor leaves were directly extracted as depressants by using simple physical methods. The active ingredients and depression mechanism were studied through contact angle measurements, Fourier transform infrared spectroscopy (FTIR), and atomic force microscopy (AFM). The flotation experiment showed that camphor leaf extract (CLE) had a strong depression effect on calcite but minimal effect on scheelite. The adsorption morphology detected using AFM confirmed the existence of active ingredients on calcite. FTIR results indicated that the adsorbed components on the surface of calcite contained a large number of hydroxyl groups that made calcite hydrophobic. Zeta potential measurements and FTIR revealed a much higher adsorption amount of CLE on the calcite surface than on the scheelite surface. The CLE has potential application value in the flotation separation of scheelite and calcite.
Key words: scheelite; calcite; flotation; camphor leaf extract; depressant