Precipitated calcium carbonate has been recognized as the most used additive and filler in paper industries, healthcare sectors, and polymer industries.
When the purified calcium carbonate is precipitated, its physical properties differ from that of the ground precipitated calcium carbonate.
The distinctive physical properties of precipitated calcium carbonate make it a suitable choice for industrial applications. The size and shape of PCC particles depend on various factors such as temperature, pH, supersaturation, and additives.
With the increase in temperature, the speed of chemical reactions also increases tremendously. This affects the PCC strength gain.
When the temperature rises, the hydration rate of the reaction also increases, thus increasing the strength gain. The optimum temperature during the carbonation ranges between 47.5℃- 65℃.
Higher temperatures are often considered better for the formation of aragonite precipitated calcium carbonate to yield higher concentrations
Furthermore, the particle size also changes with temperatures. As the temperature rises, the particle size of calcium hydroxide also increases.
When calcium hydroxide is prepared at higher temperatures, the particle size of precipitated calcium carbonate increases. Additionally, it also increases the yield of aragonite.
At lower supersaturation, the induction period for CaCO3 precipitation increases.
Furthermore, the presence of Mg2+ results in the formation of Mg-calcite compounds. However, as the concentration of ions increases, the concentration of Mg-calcite formed decreases.
The increase of magnesium additive also increases the amount of aragonite. As the amount of additive increases, the longitude and aspect ratio of aragonite starts decreasing.
Magnesium is the most common additive used in obtaining pure aragonite. Many organic and inorganic additives, containing magnesium, are used for the same.
The type of ions added in the parent solution affects the physical properties of the crystal-like its crystallinity and shape.
When citrate ions are added to the solution, it decreases the crystallinity of aragonite crystals. Whereas the magnesium ions do the complete opposite.
Citrate ions form rod-like aragonite crystals and granular calcite crystals. In comparison, the phthalic ions form rhombohedral-shaped aragonite crystals when added to the parent solution.
The majority of calcium carbonate powder manufacturers use varied sizes of calcium hydroxide to yield a variety of sizes of aragonite crystals.
This process involves the hydration reaction of calcium oxide at a temperature range of 10-80℃ and adding an aqueous solution of sodium carbonate.
Furthermore, the particle size of aragonite crystals increases with the rise in temperature and concentration of calcium hydroxide. Thus during the carbonation process, the size of the particles increases.
In addition to the above-mentioned, the particle size of aragonite precipitated calcium carbonate is also affected by the concentration of CO2 bubbles. The particle size also reduced with the reduction in the size of the bubbles.
Applications of aragonite PCC
Aragonite PCC has achieved huge success and is copiously used in various industries. Its large aspect ratio is the key factor that has led to its usage as an inorganic filler.
Aragonite PCC is used as a filler for rubber, plastic, pigment, paper, and polypropylene resins. It is said to increase the mechanical and optical properties of the aforementioned products.
The Paper industry is the leading consumer of aragonite PCC. It is believed to enhance the brightness, opaqueness, ink absorption, smoothness, and scattering of light.
Furthermore, increasing the concentration of aragonite PCC in a paper increases the mechanical properties all the while decreasing the paper cost.
Wrapping Up
Apart from these there are a whole lot of other factors that affect the properties of aragonite PCC. Knowing these properties help the calcium carbonate powder manufacturers to produce the perfect precipitated calcium carbonate.
Aragonite PCC is the most used filler in the paper industry. Considering its various uses in industrial applications, it is important to keep check of the physical properties that affect it.
ShreeKarniChemicals is one of the leading calcium carbonate manufacturers in India. We provide the best quality of material and services to our consumers.
November 14, 2022
November 14, 2022
November 4, 2022
October 14, 2022
October 13, 2022
Leave a Reply