The Effects of Ultrasonication on the Precipitation Of Precipitated Calcium Carbonate (PCC) Through Mineral Carbonation in a CaCl2-NH4 Cl-NH3-H2O SYSTEM

Abstract

The effects of ultrasonication on the precipitation of precipitated calcium carbonate (PCC) based on mineral carbonation are investigated in a CaCl2-NH4Cl-NH3-H2O system. The experimental results show that high ultrasonic power can delay the induction period of the reaction, and that the pH and conductivity change little as the ultrasonic power changes. The structure of PCC changes from mature, large and spherical particles into aggregates composed of a large number of loose crystals, and a larger proportion of vaterite transforms into calcite under an ultrasonic power of 0% to 30%, which leads to the ultrasonic scouring action. When the ultrasonic power is increased to 60% and 90%, the particle size of PCC decreases, and the proportion of vaterite increases as the ultrasonic power increased further as a result of the high saturation during the prolonged induction period induced by ultrasonication and of the high-power ultrasonic waves shattering the agglomerates rather than scouring the crystal surface.