Journal of Chemical Engineering of Japan, Vol.49, No.5, 445-451, 2016
Kinetics of Cerussite Leaching in Sulfamic Acid Solution
The leaching of cerussite kinetic was investigated using sulfamic acid solution as lixiviant. Results showed that 30 min was the optimum time to achieve over 95% lead extraction under the following leaching conditions: temperature of 60 degrees C, stirring speed of 1,000 rpm, average particle size of 60 mu m, and sulfamic acid concentration of 0.3 mol/L. The leaching process was controlled by the shrinking core model for surface chemical reaction. The leaching rate increased with increased reaction temperature, stirring speed, and concentration, as well as with decreased particle size. The apparent activation energy was 47.57 kJ/mol, and the reaction orders with respect to stirring speed, sulfamic acid concentration, and particle size were 1.683, 1.165, and -0.764, respectively. XRD and SEM analyses indicated that cerussite almost was completely dissolved and leaching residues included quartz. Therefore, sulfamic acid solution can be used as effective lixiviant for lead extraction from cerussite.