It’s a non-toxic odourless compound found as a white mineral and which occurs naturally in limestones, chalks and marbles. Commercially, it is produced in two different grades. Both are industrial and are based primarily on particle size and characteristics of the products. The two grades include ground calcium carbonate and precipitated calcium carbonate.
1. Precipitated calcium carbonate-The production of this grade occurs through chemical precipitation in a carbonation process or as a product of another bulk chemical process. The crystal shape of the product and its particles are uniform and regular having a narrow size distribution.
2. Ground calcium carbonate-its produced through the extraction and processing of calcium carbonate deposits that occur naturally. The crystal shapes of this chemical are irregularly rhombohedral and have wider sized distribution.
Due to the small size of precipitated CaCO3 particles, the grade tends to be of higher purity, is less abrasive and has a higher brightness as compared to the ground CaCo3 particles.
Applications of calcium carbonate include:
i) In the medical field, the compound is used as an anti-acid as well as a calcium supplement.
ii) It is applied as a filler and pigment in cosmetics and is added to swimming pools as a pH corrector.
III) It’s widely used in the pulp and paper industry to produce whiter, higher quality pigments as compared to other minerals.
iv) It also has construction applications. Here it is used as a filler in concrete which increases its durability and appearance. is is also used to purify metals.
v) It is used as an additive for human and livestock food products which act as vitamin supplements.
vi) It is used in water purification in water and treatment plants to remove impurities and acidity.
vii)It is also used as a fertilizer for pH stabilization in soil and as a calcium additive.