Studies on the Processing of Fine Dusts from the Electric Smelting of Ilmenite Concentrates to Obtain Titanium Dioxide

Abstract

This article presents studies on the ammonium fluoride processing of dusts from the reduction smelting of ilmenite concentrate with separation of silicon to obtain titanium dioxide. Optimal conditions for pyrohydrolysis of titanium fluorides were determined. The effects of temperature and duration on the process were studied. The optimal conditions for pyrohydrolysis of titanium fluorides were a temperature of 600 °C and duration of 240–300 min. The degree of titanium fluoride conversion to titanium oxide was 99.5% at these conditions. Titanium dioxide obtained by pyrohydrolysis of titanium fluorides was purified from iron, chromium, and manganese impurities. The effect of hydrochloric acid solution concentration, S:L ratio, and the process duration on the purification degree of titanium fluoride pyrohydrolysis was studied. The following optimum purification conditions were determined: hydrochloric acid solution concentration 12.5–15 wt%, temperature 25–30 °C, S:L = 1:6÷8, duration 20–30 min. The purified titanium dioxide consisted mainly of anatase. The pigmented titanium dioxide of rutile modification with 99.8 wt% TiO2 was obtained after calcination at 900 °C for 120 min.

Technology for Complex Processing of Electric Smelting Dusts of Ilmenite Concentrates to Produce Titanium Dioxide and Amorphous Silica

“…High quality of pigmental titanium dioxide is provided by the rutile phase; therefore, titanium dioxide was calcined at a temperature of 900 • C for 2 h to obtain the rutile modification. The TiO 2 content was 99.8 wt%, and the content of impurities of silicon, chromium, manganese, and iron in recalculation on their oxides was 0.0005, 0.032, 0.005, and 0.039 wt%, respectively, in the obtained rutile product [36]. According to the content of the main component and accompanying impurities, the product complies with the requirements of the state standard GOST 9808-84 for pigment titanium dioxide [37].…”

“…Obtained fluoride sublimations of titanium have the following composition (wt%): 59.0 Ti; 0.6 Fe; 0.005 Si; 0.09 Cr; 0.14 Al; 20.4 F; and 19.8 O. Studies of titanium fluoride pyrohydrolysis with the investigation of the influence of temperature (in the range from 300 to 700 • C) and duration of the process (in the range from 1 to 5 h) have shown that optimal parameters are 600 • C and a duration of 4-5 h [36].…”

“…Information about the use of fluoroammonium treatment in the available patent and scientific literature refers to natural titanium-containing raw materials. There are sporadic studies on the application of the fluoroammonium-processing method to titanium slurries with the production of calcium nitrate and titanium dioxide [28,29]. Silicon with alkali forms a water-soluble sodium silicate; therefore, in our previous studies [30], to separate silicon from titanium, electric smelting dust of ilmenite concentrate was leached with a sodium hydroxide solution.…”

Study of the leaching process for dust chamber sublimates followed by the extraction of niobium and zirconium into solution

“…The high rates of development of these technology branches determine the continuous increase in demand for rare metals which provides for further expansion of their production [ [1], [2], [3]]. The use of titanium-magnesium production waste abundant in rare metals can contribute to solving this problem [4]. Niobium and zirconium are a common satellite of titanium; therefore, they are found in titanium concentrates obtained from ores of ilmenite deposits.…”

Recovery of Non-Ferrous Metal from Metallurgical Residues

“…They also proposed an experimental study on ultrasound-enhanced sulfuric acid leaching for zinc extraction from zinc oxide dust [5]. Ultarakova et al present studies on the ammonium fluoride processing of dust from the reduction smelting of ilmenite concentrate with silicon separation to obtain titanium dioxide [6]. Optimal conditions for pyrohydrolysis of titanium fluorides were determined.…”