Mendeleev University of Chemical Technology (Moscow, Russia):
Kuzin E. N., Associate Professor, Candidate of Engineering Sciences, e.n.kuzin@muctr.ru
Kruchinina N. E., Dean, Doctor of Engineering Sciences, Professor, krutch@muctr.ru
Fadeev A. B., Postgraduate Student, fadeev89@mail.ru
Nosova T. I., Student, nti16041998@gmail.com

As part of the research, a technology for pyrometallurgical processing of quartz-leucoxene concentrate was proposed that includes quartz-leucoxen grinding and sintering at 1450 °С with the addition of iron (II) or (III) oxide. It has been found that, regardless of the type of iron-containing additive used (iron (II) or (III) oxide), the final sintering product will be represented by pseudobrukite. The presence of rutile and hematite impurities in it indicates an incomplete reaction and requires further optimization. The recovery of titanium compounds from the samples obtained using sulfuric acid solutions with various concentrations was, on average, four to five times higher than that of the initial quartz-leucoxene concentrate. It is noted that an increase in the acid concentration of over 80 % leads to lower recoveries of titanium compounds into the solution. Based on the results obtained, an assumption was made on the possibility of using the products (pseudobrukite) generated in the processing of quartzleucoxene concentrate as a raw material for the production of titanium compounds by the traditional sulfuric acid methods. According to the preliminary calculations, the proposed principle of joint pyrohydrometallurgical processing of quartz-leucoxene concentrate will reduce the cost of titanium dioxide production by almost 1.5 as compared to the autoclave leaching technology.
The work was carried out within the framework of the program to support young scientists and teachers of the D.I. Mendeleev University of Chemical Technology (application No. Z-2020-013.).

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