The Influence of Experimental Factors on Calcium Carbonate Morphology Prepared by Carbonation

The study of the precipitated calcium carbonate, (PCC) has received much attention owing to the wide applications. Calcium carbonate has three kinds of crystal polymorphs: calcite, aragonite and vaterite. The control of crystal shape, size and morphology is fundamental from the viewpoint of technical application. The work has as main aim establishing the influence of the initial concentration of solution, temperature and stirring speed in the obtaining process of the precipitated calcium carbonate having imposed properties by carbonating Ca(OH)(2) suspensions. It was studied the influence of conditions over the shape and size of particles. Solid obtained was analyzed from the view point of its chemistry (IR spectra), granulometric distribution and morphology by SEM. The carbonation process was monitored by pH and conductivity adjustment. The necessary carbonation time varies linearly with the suspension concentration. Increasing the gas flow rate causes a decreasing of carbonation time. Increasing the stirring speed leads to a decreasing of the particle size. The most significant influence on the particle morphology and size is represented by the initial concentration of suspension.