Titanium hydroxide as precursor for obtaining functional materials
It was found that finely ground powders can polymorphically transform into other nonequilibrium crystalline phases in the study of phase transformations of X-ray amorphous titanium hydroxide (TH) in the process of mechanical activation in the presence of additives in the form of zinc compounds. Judging by the increase in the intensity of the peaks in the diffraction patterns, it can be stated that amorphous phase crystallizes in the form of anatase and brookite as a result of high-energy exposure. It is shown that the lower the degree of hydration of titanium hydroxide, the efficiency of the mechanical effect of the additive on phase transformations is higher. The following trend for the effect of the introduced modifier is observed — ZnSO4·7 H2O > > Zn(NO3)2·6 H2O > ZnO. This dependence is due to the combination of physical and chemical transformations of the material located in the field of intense mechanical influence, confirmed by data on the calculation of crystallite size and microstrains. The conversion of excess mechanical energy into thermal energy initiates chemical processes with the formation of solid titanium-zinc solutions, which accelerate the restructuring of the crystalline structure upon calcination of the modified titanium hydroxide according to the scheme: anatase-brookite-rutile. The obtained results have the prospects of practical application in the production of the so-called “rutile” nuclei used in the industrial production of titanium dioxide for various purposes.