Solubility of TiO2 in NaF-CaF2-BaF2 Melts

• Published in: Metals and materials international Vol. 24; no. 6; pp. 1386 - 1393
• Main Authors: Yoo, Jeong-Hyun, Cho, Sung-Wook
• Format: Journal Article
• Language: English
• Published: Seoul The Korean Institute of Metals and Materials 01-11-2018; Springer Nature B.V; 대한금속·재료학회
• Subjects: Barium fluorides; Calcium fluoride; Characterization and Evaluation of Materials; Chemistry and Materials Science; Dissolution; Engineering Thermodynamics; Enthalpy; Heat and Mass Transfer; Machines; Magnetic Materials; Magnetism; Manufacturing; Materials Science; Melts; Metallic Materials; Processes; Sedimentation; Solid Mechanics; Solubility; Titanium; Titanium dioxide; 재료공학; NaF-CaF; Partial molar enthalpy; Saturation concentration; BaF; Solubility; melts; Titanium dioxide
• ISSN: 1598-9623; 2005-4149
• DOI: 10.1007/s12540-018-0156-x

The solubility of TiO
2
in NaF-CaF
2
-BaF
2
ternary eutectic melts was investigated at the temperature range of 1025–1150 °C. The least-squares equation was obtained from the relationship between the reciprocal temperature and the natural logarithm of the titanium concentration in the melts saturated with TiO
2
. The corresponding partial molar enthalpy of dissolution of TiO
2
was found to be 188 kJ/mol. The titanium saturation concentration was 3.73 wt% at 1100 °C. From the titanium concentration change with the added amount of TiO
2
at different holding time after a final stirring, it was found that not only complete dissolution of TiO
2
but also enough sedimentation of excessive TiO
2
should be guaranteed to obtain more reliable solubility data. The holding time of 10 h was found to be enough for the excessive TiO
2
particles to settle down in our experimental conditions. It is noteworthy that in case of adding TiO
2
in excess of its solubility, the Ba
1.12
(Ti
8
O
16
) phase was observed at the lower and bottom of the solidified salt ingots.