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With the rapid development of the chloride process titanium dioxide and titanium sponge industry, the increasing demand of titanium-rich material, titanium dioxide industrial consumption of titanium-rich material in the world accounting for 75% of the total raw materials, and our use of Ti-rich only 7.5% of the consumption of the perovskite material, titanium-rich material in China is still relatively large gap with foreign countries, has broad prospects for development. Of titanium-rich material is mainly an electric furnace melting method, backward production technology, small-scale, low efficiency, pollution, high energy consumption, operational stability, which to some extent affected the development of China's titanium industry. This thesis, a new technology for titanium concentrates preparation of titanium-rich material, prepared Ti02 content greater than 95%, MgO CaO content is less than 1.2% of the titanium-rich material, chlorination can be used as raw material for the production of titanium dioxide and titanium sponge. Test uses the Wuding a titanium concentrates as raw materials, through the x-ray diffraction and electron microprobe analysis showed that the titanium concentrates mainly ilmenite, followed by Ti - magnetic hematite, limonite mineral phase. Titanium Concentrate TiO2, FeO, Fe2O3, MgO, CaO, SiO2 is not a stand-alone, but context-like presence of titanium concentrate, calcination reaction will have an important impact on leaching effect. The experiment shows that if the direct use of sulfuric acid leaching of titanium concentrate, concentrate titanium only a small part of the solution In order to improve the rate of acid hydrolysis pretreatment of titanium concentrates test titanium concentrates and mixed alkali roasting method and achieved good test results. The titanium concentrate mixed with alkali roasting thermodynamic analysis shows that: When the T GT; 957K, TiO2, SiO2, Al2O3 and sodium carbonate reaction the △ GTθ of less than zero; when T LT; 2000K, TiO2, SiO2, Al2O3 and hydroxide The sodium reaction △ GTθ less than zero, indicating that the reaction is feasible in the thermodynamic theory of titanium concentrate with an alkali mixed calcined. Test studied by orthogonal test, suitable calcination conditions: The the titanium concentrate mixed with sodium hydroxide calcination temperature to 600 ° C, roasting time 5h, alkaline mineral ratio of 1.8:1, the calcination reaction will in more partial sodium titanate and sodium titanate generation, help to improve the rate of acid hydrolysis; calcined product ground to -200 mesh, a concentration of 98% sulfuric acid diluted acid solution can achieve better acid solution effect of the highest acid hydrolysis rate can reach 96%, determined by experiments suitable acid hydrolysis conditions: leaching temperature of 90 ° C, acid mine than 3.84:1, sulfuric acid concentration of 80%; including factors that affect the hydrolysis of titanium liquid hydrolysis temperature , hydrolysis time, stirring rate, and the titanium concentration, F value, the ratio of iron to titanium, trivalent iron content, clarity and stability. The test focuses on the hydrolysis temperature, hydrolysis time and a stirring rate of hydrolysis of the titanium liquid, the preferred hydrolysis conditions obtained by the comparative tests: hydrolysis temperature of 90 ° C, the hydrolysis time for 4h, and the stirring rate is 70r/min. Through the entire trial to determine the suitable titanium concentrates made directly from the new process for the titanium-rich material: titanium ore with alkali at a certain temperature roasting, generate a the partial sodium titanate and a small amount of sodium titanate, partial sodium titanate and sodium titanate was dissolved in hot acid at room temperature and under atmospheric pressure, titanium solution was obtained by filtration and then subjected to hydrolysis of the titanium liquid, calcination of the hydrolyzate can be obtained Ti02 content greater than 95% of the titanium-rich material.
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