Kinetics of titanium extraction at hydrometallurgical fluoridation of titanomagnetite ore

This paper presents a study of the kinetics of titanium leaching during fluorammonium hydrometallurgical proces sing of titanomagnetite ores from the Chinea deposit. A series of experiments was conducted to determine the kinetic parameters over a range of process durations. Two leaching solutions were employed to investigate the kinetics of the process, and the composition and concentration of these solutions were identified as optimal for achieving the maximum level of titanium and vanadium extraction into solution. The concentration of (NH4)+ in both solutions was 0.4 mol/L, while the concentration of (F)– for solution 1 was 0.8 mol/L and for solution 2 was 0.9 mol/L. It was observed that the rate of titanium recovery declines with the passage of time. At approximately 10 hours, the rate of recovery reaches a plateau. In the initial five hours of leaching, the graph is linearised in the coordinates of the ‘shrinking sphere’ model. The results of calculations for the second section, with a duration of between 5 and 25 hours, are linearised in the coordinates of the Yander equation. The value of the apparent activation energy falls within the range Ea ∊ (30; 71) kJ/mol, indicating that the leaching process occurs in a kinetic regime. This study was supported by the Tomsk State University Development Programme (Priority-2030).