Effect Mechanism Of Inorganic Depressants On Flotation Sepration Of Ilmenite From Titanaugite

Titanomagnetite resources is enriched in Pan-Xi Region of China, where is the largest base of producing V-Ti material in China. Because of limited beneficiation technique, Particle fraction of-19μm can not be effectively recovered, resulting in a large of metal loss. Therefore, carrying out research on technology of ilmenite beneficiation, especially research on basic theory is very important and necessary.In this thesis, effect of several inorganic depressants on flotation behavior of ilmenite and titanaugite were studied using sodium oleate as collector by flotation tests. Including phosphorus-containing depressants (sodium hexametaphosphate, sodium polyphosphate), and silicon-containing depressants (sodium fluorosilicate, water glass, modified water glass). Interaction mechanisms between flotation agents and minerals had been studied by the measurements of zeta potential, the adsorption of flotation agents, Infrared spectroscopic and X-ray photoelectron spectroscopy (XPS). Main contents and results are obtained as following:In the pure mineral flotation tests, flotation behavior of ilmenite and titanaugite were different. The floatability pH range of ilmenite was 5-10 while that of titanaugite was 5-7.Under the condition of weak acid (pH=5-5.5), the effect of four depressants on flotation behaviour of titanaugite and ilmenite were investigated. The result showed that order of depressant ability of four depressants was indicated as follows:water glass> sodium fluorosilicate≈sodium hexametaphosphate>sodium polyphosphate.It was found that depressant ability order of different modulus water glass on ilmenite was 3.3>2.4>2.8>2.0 while that of titanaugite was 3.3>2.8> 2.4>2.0. Depressing ability of acid water glass was stronger than that of water glass. Salt water glass had no effect on selective separation ilmenite from titanaugite.Chemcial adsorbtion occured on the surface of titanaugite, forming chemical bonds between the water glass and Fe, Mg and Al atoms on the surface of titanaugite. However there were little obvious chemical bonds on the surface of ilmenite.Mechanism of water glass separating ilmenite from titanaugite can be considered that the water glass could effectively prevent the adsorption of sodium oleate onto the surface of titanaugite while have nothing to do with ilmenite. Namely, competitive adsorbtion occurred in the system of pulp, as a result, reducing the adsorption of collector on titanaugite.Based on the investigation, a novel flotation separation flowsheet for ilmenite was given. That is technology for recovering whole size range. Using reagent maily with fatty acid as collector while water glasss as depressant. In the situation of TiO2 grade 8.31% in the feed, if only one roughing, the rough concentrate containing about 24.41% TiO2 with a recovery of 68.84% can be obtained. Also TiO2 grade of tailing is very low with 1.34%.