Titanium smelting
Time: 2013-07-25 23:51
Titanium Resources in China total 965 million tons, ranking first in the world, accounting for 38.85 percent of the world's proven reserves, mainly in Sichuan, Yunnan, Guangdong, Guangxi and Hainan, which is China's largest titanium panxi resource base, titanium resource of 870 million tons. The perovskite Yunnan mainly distributed in wuding, Luquan, Maitreya, Dali, Tengchong, Jinghong and enriching six large area, or sift through the census work has identified 30 industrial deposits, including 15 large and medium-sized 5, a small 10. Yunnan titanium is mainly ilmenite, its good quality and low impurities, relatively easy to produce 90% to 92% of TiO2.
Titanium smelting raw materials are generally used rutile and ilmenite. Rutile is a relatively pure titanium dioxide, typically containing more than 95% TiO2. Ilmenite is an iron and titanium oxide minerals, composed of FeTiO3.
Common industrial sulfuric acid decomposition method of preparation of ilmenite, titanium dioxide, and then by the preparation of titanium dioxide titanium. Grated concentrated sulfuric acid ilmenite (concentrate), the following chemical reactions occur: FeTiO3 +3 H2SO4 == Ti (SO4) 2 + FeSO4 +3 H2O
FeTiO3 +2 H2SO4 == TiOSO4 + FeSO4 +2 H2O FeO + H2SO4 == FeSO4 + H2O
Fe2O3 +3 H2SO4 == Fe2 (SO4) 3 +3 H2O in order to remove impurities Fe2 (SO4) 3, adding iron, Fe3 + reduced to Fe2 +, and then the solution was cooled to 273K or less, making FeSO4 • 7H2O (green vitriol) as a byproduct crystallization .
Ti (SO4) 2, and parse out the water TiOSO4 Metatitanic white precipitate, and the reaction is:
Ti (SO4) 2 + H2O == TiOSO4 + H2SO4
TiOSO4 +2 H2O == H2TiO3 + H2SO4 metatitanic which obtained calcined titanium dioxide:
H2TiO3 == TiO2 + H2O
Industrial manufacture of titanium metal thermal reduction method using titanium tetrachloride. The TiO2 (rutile or natural) and charcoal powder are mixed and heated to 1000 ~ 1100K, chlorination, and to generate TiCl4, vapor is condensed into liquid.
TiO2 +2 C +2 Cl2 = TiCl4 +2 CO
Metal thermal reduction reducing titanium tetrachloride titanium sponge obtained in two ways:
Na reduction method (Hunter):
TiCl4 +2 Na == TiCl2 +2 NaCl
TiCl2 +2 Na == Ti +2 NaCl
Mg reduction method (Kroll):
TiCl4 +2 Mg == 2MgC12 + Ti
At 1070K with molten magnesium protection of argon gas may be a porous reducing TiCl4 titanium sponge.
Titanium sponge is a sponge-like metallic titanium. Purity% (mass) is generally 99.1 to 99.7. Impurities% (mass) amount of 0.3 to 0.9% oxygen impurity elements (mass) of 0.06 to 0.20, hardness (HB) of 100 to 157, according to the purity MHTi4 WHTiO divided into five levels. This porous "sponge titanium" can not be directly used, they must also be vacuum arc or electron beam melting furnace (Electro-beam abbreviated EB furnace) melted into a liquid, in order to cast titanium ingots.
