Kinetics of titanium dioxide precipitation by thermal hydrolysis

Preparation and Photoactivity of Nanocrystalline TiO2 Powders Obtained by Thermohydrolysis of TiOSO4

“…The hydrolysis of TiOSO 4 has been widely studied and in particular, the formation mechanism [7,11], the precipitation procedure [7], and the thermal hydrolysis kinetics [8,12] have been examined. The effect of post-treatments on the powder morphology [20] and the properties [14] of TiO 2 have been also investigated.…”

Experimental and theoretical investigations of the coating of capsules with titanium dioxide

“…2]. After the hydrolyzation the titanium oxide hydrate forms oxo (olation) and hydroxo (oxilation) bridges while oxo bridges are favored by higher temperatures [3]. In this condensation process gel particles are formed which on the other hand can dissolve again.…”

“…The process which is mainly used for its production is the sulphate process. In this process naturally occurring ilmenite (FeTiO 3 ) is reduced to titanium slag at 1200 • C and treated with concentrated sulphuric acid and scrap metal to reduce Fe 3+ to Fe 2+ which would otherwise lead to impurities of precipitated Fe(OH) 3 . By a subsequent treatment with water at temperatures below 85 • C the titanium dissolves in form of TiOSO 4 and, after removal of FeSO 4 ·7H 2 O by cooling crystallization, titanium oxysulphate can be hydrolyzed to titanium oxide at elevated temperatures [1].…”

“…Agglomerates on the other hand were formed at low supersaturations while the particles were mainly bound by weak bonds where SO 4 2− bridges play a major role. Since he found Nomenclature Symbols A specific surface (m 2 g −1 ) B nucleation, birth rate (m −3 s −1 ) c concentration (mol L −1 ) C c molar density of crystals (mol m −3 ) d stirrer diameter (m) d 4, 3 volume weighted mean diameter (m) D death rate (m −3 s −1 ) D AB diffusion coefficient (m 2 s −1 ) g growth rate exponent G growth rate (m s −1 ) I s degree of segregation k B…”

Surface modification of silicon nitride nanofibers with titanium nitride particles

“…Of the processes for producing nanocrystalline anatase TiO 2 , hydrothermal methods using amorphous TiO 2 [5], TiCl 4 [6][7][8][9], or an aqueous TiOCl 2 solution [7] and sol-gel methods using titanium alkoxides [10,11] merit much attention. Titanium dioxide can be obtained by direct hydrolysis in solutions of titanium compounds such as tetrachloride TiCl 4 [12][13][14] or alkoxide Ti(OR) 4 [15,16]. Titanium dioxide can also be obtained using an aqueous peroxytitanate solution [17].…”