Modified calcium carbonate

The so-called modified calcium carbonate means that the surface of heavy calcium carbonate or light calcium carbonate can be activated, not only hydrophobic but also activated. The modified calcium carbonate has a molecular formula of CAC03, a molecular weight of 100.09, an alias colloid calcium carbonate, and a Japanese commodity name is white Yanhua, also known as active calcium carbonate. China has a vast territory, rich in quality limestone, and active development of active calcium carbonate production, to meet the needs of rubber, plastics, paper, paint and other industries have important practical significance.
1. Properties of modified calcium carbonate
The modified calcium carbonate is a very fine white powder, odourless and tasteless. The particle is similar to the sphere. The particle size is below 0.1um, and a layer of fat soap is adsorbed on the surface of the particles. Therefore, the colloid activation performance is a fine white reinforcing filler. Dissolve in water, decompose with acid, burn to become burnt black, release carbon dioxide and produce calcium oxide.
Two, the application of modified calcium carbonate
Modified calcium carbonate is a widely used filler used in rubber, plastic, paper, paint, paint, printing, cable, leather, medicine and food industries. Its main characteristics are that the particle size is less than 0.1um, the particle size is more uniform, the specific surface area is large, the application performance is much better than the ordinary calcium carbonate, the filler of the PVC cable material, synthetic leather, polyethylene film, foam plastic slippers and so on is widely used. Plastic products filled with activated calcium carbonate can improve the impact resistance. As a rubber supplement, active calcium carbonate is added to rubber products, its mechanical properties are obviously improved, such as tearing strength can be increased more than one times, flexing times can be increased by 5-6 times, so active calcium carbonate is both rubber filler and rubber reinforcing agent. In China, the rubber industry is the largest user of calcium carbonate, and the annual consumption is more than half of the total calcium carbonate. Activated calcium carbonate has good whiteness and fineness, and can be used in paper making and coating industry to improve the quality of paper and coatings. In addition, active calcium carbonate can also be used as a filler for medium and high grade ink, with good gloss and transparency, and dispersibility and fluidity can meet the requirements of high-grade ink filler.
Three. Production process of modified calcium carbonate
The production process of modified calcium carbonate is roughly the same as that of light calcium carbonate production, but in the process of carbonization, strict control conditions should be made to produce fine Calcium Carbonate Granules and use activator for surface treatment. The mixing of limestone and coal is about 7.5, which is about 7.5, and at 900-1000 temperature in the lime kiln. The carbon dioxide is sent to the carbonation tower in the lime kiln. The carbon dioxide is sent to the carbonation tower, the lime is fed into the digestion tank, and the lime is digested with 80-90 centigrade hot water to make 'the emulsion of about 9%, into the carbonization tower, carbonized through carbon dioxide, and when carbonized, suspension liquid. When the pH value is equal to 7, it is the end point of the reaction. With dry surface treatment and wet surface treatment, wet surface treatment process is usually used, because the method can produce active calcium carbonate with high activity, good dispersibility and high transparency.