Study On Flotation Behavior Between Kyanite And Quartz

Kyanite is important raw material of refractory material,alumina and silicon-aluminum alloy. With rich kyanite resources sharp-cut-off in China, development and utilization of low-grade kyanite resource is imminent. The study of separation of kyanite and quartz is a difficult problem, which may improve the recovery of low-grade kyanite resources and quality of products. Thesis focused on the impact of metal ions and sodium silicate, trying to find out how they affect the flotation separation of kyanite and quartz and their influencing regularities, so as to provide theoretical support for kyanite flotation separation process.The study include three aspects:single mineral flotation tests, artificial mixed mineral flotation tests and mechanism of collector action with the mineral surface.The result of single mineral flotation tests showed that Al3+ and Fe3+ place activation effect on kyanite while pH<4.0, and the activation strength of Al3+ is greater than Fe3+, however, Ca2+ and Mg2+ place disincentive effect on kyanite. At the same time, Al3+ and Fe3+ play a activation effect on quartz, and the activation strength of Al3+ is far more than Fe3+, while Ca2+ and Mg2+ play a disincentive effect under acidic condition.Further studies showed that Fe3+ have intensity disincentive effect on kyanite at low concentrations and activation effect at high concentrations. The sodium silicate can restrain kyanite and quartz which activate by Fe3+, moreover, the separation of kyanite and quartz achieve optimum efficiency when the concentration ratio of Fe3+ and sodium silicate is 10:8.3. However, sodium silicate can not restrain kyanite and quartz which activate by Al3+, on the contrary, activate the kyanite and quartz, so the sodium silicate can not be used as its inhibitor. In addition, the impact of particle size on kyanite floatability is greater than that in quartz, and the floatability of coarse kyanite is far less than fine particle, what's more, to reach the similarity floatability coarse particle needed much more collector than the fine-level ore.The result of artificial mixed mineral flotation tests showed that kyanite and quartz can separation effectively when the concentration ratio of Fe3+ and sodium silicate is 10:8.3, the yield of concentration is 50.98%, and grade of kyanite is 94.26%, the recovery reached 96.11%.The result of mechanism of collector action with the mineral surface texts showed that the Zeta-potential of kyanite moved to the negative value strongly after adsorption collector, PZC dropped from 6.6 to 1.8, and the collector effect in kyanite surface with chemical and physical adsorption. In acid conditions, Ca and Mg cations exist in the form of Ca2+ and Mg2+, which are dominant components and place disincentive effect on kyanite. However, Fe and Al cations produce hydroxyl complex while hydration, and the hydroxyl complex play a activate effect on kyanite.