Removing of Si in the NaOH Molten Salt Reaction of Titanium Slag to Produce TiO₂

Abstract:

NaOH solution was utilized in the molten salt reaction of titanium slag for investigating desiliconization effects. The thermodynamic behaviors of Si in the reaction system was examined to explore the impacts of molten salt reaction conditions on the conversion rates of the foreign substance Si and the target element Ti. On this basis, the influences of NaOH concentration, liquid-solid ratio, cleaning temperature and cleaning time on Si removing rate were discussed. The experimental results showed that, Si reacted with NaOH to produce sodium silicate was feasible in terms of thermodynamics within the temperature interval 400-1000K. 3Na₂O•2SiO₂, 2Na₂O•SiO₂ could stably exist under high reaction temperature. As the reaction time extended and temperature rose, the conversion rate of Si was increasing. In the process of Si removing by NaOH cleaning of molten salt reaction products, as NaOH concentration, liquid-solid ratio, cleaning temperature and cleaning time increased, Si removing rate became larger. The optimum alkali cleaning conditions were: NaOH concentration 150g/l, liquid-solid ratio 3:1, cleaning temperature 50°C and cleaning time 60min, then the desiliconization rate reached 61.16%.

• Periodical: Advanced Materials Research (Volumes 418-420)
• Pages: 387-392
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.418-420.387
• Online since: December 2011
• Authors: Yan Fang Han, Ti Chang Sun, Jie Li, Li Na Wang, Tian Yan Xue, Tao Qi
• Keywords: Desiliconization, Molten Salt Reaction, NaOH Cleaning, Titanium Slag

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