Decomposition of acid dissolved titanium slag from Australia by sodium hydroxide

et al. 2013

Ind. Eng. Chem. Res.

Self Cite

Titanium dioxide (TiO 2 ) has been widely used as pigment in paints, fillers for plastic and paper, coatings, adsorbents, cosmetics, catalysts, and gas sensors. A novel process for TiO 2 production has been developed by the Institute of Process Engineering. This work develops the novel process by using the NaOH/KOH binary molten salt (50 mol % NaOH, 50 mol % KOH) instead of NaOH molten salt. Under conditions of temperature 350°C and mixed alkali-to-titanium slag ratio 1.4:1, the titanium conversion ratio obtained is >98% with reaction time around 90 min. The kinetics investigation indicates that the decomposition of titanium slag is controlled by mass diffusion in thed residual layer and the apparent activation energy is 43.1 kJ/mol. 98% of KOH and 86% of NaOH can be recycled by a water leaching process. On the basis of the experimental results, a flow sheet was developed and tested, and the content of TiO 2 obtained in the product reached 99.5%. As the NaOH/KOH binary molten salt system provides a liquid as relatively low temperature, the energy consumption of this technology may probably be lower than that of the existing one.

Section: Resultsmentioning

confidence: 99%

“…6,7 TiO 2 rutile white pigment with good pigmentary properties was prepared via the new method. 8 A demonstration plant has been built in Shandong Province, which has approached zero emission of pollution.…”

Section: Introductionmentioning

confidence: 99%

Novel Process for Titanium Dioxide Production from Titanium Slag: NaOH-KOH Binary Molten Salt Roasting and Water Leaching

Wang

Chu

et al. 2013

Ind. Eng. Chem. Res.

Self Cite

Journal of Saudi Chemical Society

“…For these purposes treatment of ilmenite or its slag with alkali salts (Na and K) for high grade TiO 2 preparation was carried [4,[15][16][17][18][19][20]. Other investigators indicated that titanium ores can be treated with alkali salts followed by acid (H 2 SO 4 or HCl) attack for titania preparation [17,19,[21][22][23]. The present work aims to prepare pure titania sample via intermediate product produced from slag roasting process with Na 2 CO 3 using H 2 SO 4 acid solution.…”

Section: Introductionmentioning

confidence: 99%

Titania preparation from soda roasted slag using sulfuric acid solution

Manaa

2016

This work deals with treatment of the sodium titanate cake results from roasted titania slag using 60% sulfuric acid solution. The working sample produced by roasting titania slag with NaCO 3 at 850°C. After roasting V and Cr species as impurities in the roasted sample are converted to water soluble species as NaVO 3 and Na 2 CrO 4 before acid treatment however, the insoluble sodium titanate products (NaFeTiO 4 , Na 8 Ti 5 O 14 , Na 6 Ti 2 O 7 and Na 2 TiO 4 ) are then subjected to H 2 SO 4 acid dissolution. The produced sulfate solution is subjected to hydrolysis step in presence of oxalic acid as a reducing agent. The hydrolyzed precipitate after filtration and washing with H 2 SO 4 solution and warm water is dried at 100°C and calcinated at 850°C to prepare high pure TiO 2 (99.8%) besides removing ferrous sulfate (FeSO 4 ) as a byproduct from the sulfate solution. ª 2014 Production and hosting by Elsevier B.V. on behalf of King Saud University. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

“…So it is of high comprehensive utilization value . It is estimated that the yield of vanadium coming from vanadium–titanium magnetite is close to 88% each year and many studies were focused on preparing TiCl 4 , Ti‐rich material, and so on by using titanium slag. As the phase composition of high chromium vanadium–titanium magnetite is more complex than ordinary vanadium–titanium magnetite, the processes of agglomeration, blast furnace smelting, and comprehensive utilization are more difficult.…”

Section: Introductionmentioning

confidence: 99%

Reduction Process of Pellet Containing High Chromic Vanadium–Titanium Magnetite in Cohesive Zone

Cheng

et al. 2014

steel research int.

In the present study, the reduction process of pellet containing high chromic vanadium–titanium magnetite in cohesive zone has been investigated. To elucidate the reduction process including the softening and melting properties, structure changes and migration processes of valuable components (Fe, V, Ti, and Cr) in pellet containing high chromic vanadium–titanium magnetite in cohesive zone, the experiment was carried out at different temperatures and the pellet samples were analyzed by the methods of XRD, SEM, and chemical analysis. The results of reduction process show that the temperature range of cohesive zone of pellet is from 1087.9 to 1338.3 °C and the maximum differential pressure of the burden is 15 859 Pa at the temperature of 1291 °C. The reduction process of pellet was gradually conducted from outside to inside, which could form a layer of iron shell on the outer surface of the pellet. A lot of wustite could be generated in the core of pellet when the reduction temperature exceeded 1100 °C. The migration process of iron is Fe2O3 → Fe3O4 → FeO → Fe, while the generated FeO could react with SiO2 forming 2FeO · SiO2. The reduction process of titanium is Fe2O3 · 3TiO2 → Fe5TiO8 → Fe2TiO4 → FeTiO3 → Ti(O0.19C0.53N0.32) → Ti(C,N) → [Ti] and MgO · TiO2 → Ti(C,N) → [Ti]. The migration process of vanadium is V2O3 → VN, VC → [V] and the chromium oxide was reduced as follows: (Fe0.6Cr0.4)2O3 → FeCr2O4 → [Cr].