期刊
PROCESSES
卷 8, 期 6, 页码 -出版社
MDPI
DOI: 10.3390/pr8060640
关键词
altered ilmenite; titanium dioxide; rutile; sulfuric acid; fluoride ions; equilibrium Gibbs free energy; thermodynamic parameter evaluation; homogeneous-heterogeneous catalysis; chemical kinetics; leaching
资金
- R&D project of the Ukrainian State University of Chemical Technology [24/170290]
Rutile decomposition by sulfuric acid, including the formation of two salts, Ti(SO4)(2)/TiOSO4, is thermodynamically modelled. It is shown that TiO(2)can spontaneously dissolve in H(2)SO(4)solutions. However, titania is considered as an inert (ballast) phase component of titanium-containing raw materials due to the decelerated separate nature of such chemical transformations. It is concluded that the hampered related kinetics of dissolution can be attributed to the lability of Ti(IV) cations/the specific engineered features of the hierarchical crystalline structure. It is suggested that the breaking of Ti-O-Ti bonds without additional mechanical strains in crystal lattice geometry becomes more advantageous when smaller negative anions/fluoride ions can be used. The analysis of sulfate-fluoride extraction leaching of titanium confirmed that a decrease in the Gibbs energy in the presence of F occurs. It is indicated by kinetic research studies that the addition of corrosive sodium reagent (NaF) reduces the activation by 45 kJ/mol, which results in intensification. A mechanism is proposed for the interactions involving the Ti-O-Ti cleavage on the surface/the H2SO4-induced Ti dioxide degradation on the sites of defects. Moreover, F acts as a homogeneous/heterogeneous bifunctional catalyst.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据