Study on the interaction mechanism of flotation reagents and rare-earthsbearing phosphate ore

Based on ore characteristics and reagent properties, this paper sets out to study fluoro-carbon apatite and dolomite surface electrical properties, reagent adsorption form, surface wettability as well as the interaction mechanism between flotation reagents and minerals using applying contact angle measurement, χ Potential and infrared spectrum analysis, in order to provide theoretical guidance for floatation practice in low grade phosphate ore of Zhijin, Guizhou. The χ Potential metric measurement shows that χ potential varies in accordance to the pH value no matter 2.67g/L salts of fatty acid is added or not, with a negative χ potential value. In particular, χ potential decreases when 2.67g/L salts of fatty acid is added at the same pH value. This may have been resulted from the selective solution of calcium ion from the apatite lattice into acid solution, or is a result of taring anion adsorbing to the mineral surface and causing negative electrification. Infra-red spectrum analysis shows that CH3 - adsorption peak occurs at 1622.42cm-1 or 1623.13 cm-1 for tailings whereas there is no distinct CH3 - characteristic peak. All this indicates that there is adsorption of the collector salts of fatty acid on the surface of dolomite, while almost no adsorption of the collector salts of fatty acid on that of apatite. In this way, selective separation of apatite and dolomite is achieved. An contact angle measurement shows that the contact angle χ is getting smaller no matter strong acid like H2SO4 or weak acid is added, which indicates hydrophobicity decrease and hydrophilicity increase. In contrast, when the collector salts of fatty acid is added, the hydrophilicity decreases with hydrophobicity increasing. When H2SO4, weak acid and salts of fatty acid are mixed, mineral floatability falls, suggesting that fluoro-carbon apatite can not float up easily with weak acid and H2SO4 used as the inhibitor and salts of fatty acid as the collector. In this way, selective separation of collophanite and dolomite can be achieved effectively.