Calcium carbonate is an important non-metallic mineral basic raw material in daily industrial production, known as “industrial food”, and is closely related to the national economy and life. Calcium carbonate is widely used in plastics, architectural coatings, paints, papermaking, rubber, inks, pigments, adhesives, sealants, daily chemicals, toothpaste, food, medicine and other fields.
Application of calcium carbonate in polymer-based composite materials
The preparation and application of traditional calcium carbonate have been widely reported. Calcium carbonate whiskers have attracted the attention of researchers due to their columnar fiber structure and their ability to improve the tensile strength, bending strength, impact toughness and other mechanical properties of polymer materials.
Application in flame retardant materials
In terms of flame retardancy, calcium carbonate is mainly used in polymer-based composite materials, wood modification, etc., especially polymer/natural fiber composite materials. Calcium carbonate, especially crystalline calcium carbonate, can be used as a polymer reinforcing agent and a polymer flame retardant.
Application in hydrogels
Under acidic conditions, calcium carbonate can promote the regeneration of biological tissues, and calcium carbonate can be degraded in the body. Weakly acidic environments can regulate the release of calcium ions from calcium carbonate; calcium ions can form ionic bonds in hydrogels to improve the mechanical strength of hydrogels.
Application in photocatalytic materials
Studies have shown that the elimination rate of nitrogen oxides by carbon nitride after the synergistic action of cyanide defects and calcium carbonate reached 51.18%, which is significantly higher than the elimination rate of nitrogen oxides by unmodified carbon nitride of 34.05%.
Application in new energy materials
Zinc-air battery is a water-based rechargeable battery with the advantages of safety, low cost and environmental friendliness. It is a green energy storage device with development prospects. However, the capacity of zinc-air battery decays quickly and the cycle stability is poor.
Application in radiation refrigeration materials
The infrared emission groups of inorganic materials are mainly anionic groups. Calcium carbonate has good infrared emission performance in the atmospheric window (8~13 μm), and the raw materials are widely available. Shells, eggshells and other waste materials are all raw materials for calcium carbonate.
Application in thermal energy storage
Calcium carbonate has good thermal conductivity, mechanical properties, sealing properties and chemical stability, and can be used for microcapsule coating phase change materials. The prepared microcapsule cortex has good protection and a longer service life.
Application in tumor treatment
Calcium carbonate can be used as a drug release system for tumor treatment due to its low cost, easy bioabsorption and good biocompatibility. However, the typical micrometer-sized calcium carbonate has a high crystallinity, which reduces the degradation rate of calcium carbonate in the biological system and seriously damages the drug release efficiency.
Application in the field of new papermaking
Some scholars have prepared flexible and deformable calcium carbonate with a high aspect ratio using nanocellulose as a template. First, the nanocellulose is dispersed in water, and carbon dioxide is introduced after stirring evenly, so that calcium oxide generates calcium carbonate in situ around the nanocellulose. This method can make paper change from wood-based to calcium carbonate-based, reduce the use of wood, and contribute to the sustainable development of the papermaking industry.
Application in building materials
Calcium carbonate whiskers have good compatibility with cement and are often used for cement reinforcement. Ordinary concrete is prone to cracks when impacted, while calcium carbonate whiskers can control the development of cracks.
Application in water treatment
Calcium carbonate has good buffering, neutralization and adsorption properties, and can be used in water treatment and wastewater treatment. In water treatment, calcium carbonate can adjust pH, remove polluting ions and adjust water hardness, playing an important role in alleviating scale formation, preventing pipe blockage and improving water resource utilization efficiency.
Application in soil treatment
In the treatment of contaminated soil, calcium carbonate can precipitate a variety of heavy metal ions and adjust the pH of the soil, and is an important repair agent for contaminated soil.