Dissolution Behavior and Kinetics of Fine Silica Powder in Dilute Alkaline Solution
微硅粉中SiO2在稀碱液中的溶解行为及动力学

The dissolution behavior and dissolution kinetics of fine SiO2 powder in dilute alkaline solution were studied. The effects of initial concentration of NaOH, reaction time and reaction temperature on the dissolution rate of fine silica powder were investigated. XRD was used to analyze the phases of fine silica powder and leaching residue. The results demonstrated that SiO2 dissolution rate increased with initial concentration of NaOH and reaction temperature. Dissolution apparent activation energy of the amorphous SiO2 of fine silica powder in dilute NaOH solution was 18 kJ/mol. Dissolution reaction was controlled by diffusion.