<p>The Kroll process is currently the only method for large-scale production of sponge titanium in industry, which face problems such as low efficiency and high energy consumption. Vacuum distillation of titanium sponge is the most time-consuming and energy-consuming process in the Kroll process. The study of the volatilization kinetics of impurities (Mg, MgCl₂, etc.) in titanium sponge during vacuum distillation is important for improving efficiency, reducing energy consumption, and improving the quality of Ti sponge. In this paper, the volatilization kinetics of magnesium chloride and magnesium impurities during vacuum distillation of titanium sponge were investigated, and the volatilization rates of magnesium and magnesium chloride in titanium sponge were determined by using a volatilization rate measurement apparatus. The empirical equations for volatilization rate of Mg and MgCl₂ with temperature, pressure were obtained based on the experimental data of volatilization rate determined in this study, and its changing trend is described. The maximum volatilization rate was calculated using the Langmuir equation, and the cohesion factor was corrected. The mass transfer coefficients of magnesium and magnesium chloride in titanium sponge in the “free state” in vacuum distillation process at different temperatures and pressures were calculated, and the rate-limiting step were determined. This study provides reliable experimental data for improving the vacuum distillation of titanium sponge and provides a reference for the Kroll process to reduce energy consumption and improve efficiency.</p>