Research On The Extraction Of Titanium Components And The Preparation Of Series Of Chemical Powder From Ti-bearing Blast Furnace Slag

The Ti-bearing blast furnace slag is producted fro m blast furnace smelting using vanadium titanium magnetite ores. It is a kind of solid waste and a kind of mineral resources. Based on the Ti-bearing blast furnace slag rich in Mg O, Si O 2, Al₂O₃ and TiO₂ and so on a variety of valuable components, study on the utilization of Ti-bearing blast furnace slag by high temperature roasting. T he mineralogical characteristics of the slag were analyzed, according to the characteristics of mineral phase, designed two process of ?roasting using alkali and then leaching by water? and ?roasting using acid salt and then leaching by water? to carry out experimental, to extraction of the valuable components from the slag and preparation of the corresponding chemical powder. Specific research results are as follows.The main chemical components of Ti-bearing blast furnace slag are Ca O, SiO₂, TiO₂, Al₂O₃ and Mg O, etc., the main mineral composition is perovskite, diopside and spinel. The valuable components has a acid-base duality, a variety of components can be extracted from th e reaction of slag and additives. 47.52% SiO₂ and 82.97% Al₂O₃ in slag can be extracted by Na 2CO3 mixed roasting Ti-bearing blast furnace slag. A series of complex decomposition reactions occurred during the rosting process. Na 2CO3 first reacted with spinel to generate Na AlO₂, and then react with diopside to produce soluble salt Na 2Si O3 and micro-soluble substance Na2 Ca Si O4, while the perovskite is not involved in the process.50.78% SiO₂ and 87.58% Al₂O₃ in slag can be extracted by using Na OH alkali fusion Ti-bearing blast furnace slag. A series of complex decomposition reactions occurred in the alkali fusion process. Na OH react with diopside to generate Intermediate calcium magnesium olivine at 283 ?, as the reaction proceed, monticellite had reacted wit h Na OH to generate Na 2Si O3 and Na2 Ca Si O4. The temperature rises to 296 ?, spinel react with Na OH to generate Na AlO₂. When the temperatures continue to rise to 320 ?, perovskite react with Na OH to generate Na2 Ti O3. T hree kinds of minerals in alkali fusion pro cess to cause weightlessness, The product of Na 2Ti O3 will occur in self hydrolysis, crystal destruction into amorphous structure.By using Na OH alkali fusion water immersion method obtained water extract as raw material to hydrothermal synthesis of zeolite 4A under the conditions of temperature 50 ? and atmospheric pressure. T he zeolite crystal form is complete, and the microstructure is cube structure, uniform size and size distribution is 1.0¹.5 M. By using Na OH alkali fusion water immersion method obtained leaching residue as raw material to hydrothermal synthesis of zeolite 4A for the preparation of titanium dioxide, the anatase Ti O 2 powders obtained have higher purity and better crystallinity.88.14%MgO and 86.45%Al₂O₃ in slag can be extracted by NH4HSO4 mixed roasting- Ti-bearing blast furnace slag, by fractional precipitation can obtain Mg?OH?₂ and Al?OH?₃ from leaching solution. A series of complex decomposition reactions occurred during the roasting process, NH4HSO4 decomposition into intermediate?NH4?3H?SO4?2 under 238 ?, then?NH4?3H?SO4?2 react with perovskite, diopside and spinel to generate Ca SO4 and?NH4?3Al?SO4?3, With the increase of temperature,?NH 4?3Al?SO4?3 decomposed into Al2?SO4?3.This study provides a new research idea for the resource utilization of Ti-bearing blast furnace slag. Not only can solve the social and environmental problems caused by the massive accumulation of tailings, but also can create more economic value in the realization of high efficient utilization of Ti-bearing blast furnace slag.