In this study, we used the insight gained from our previous work and developed an indirect aqueous CaS carbonation process for the production of high-grade CaCO 3 (i.e. >99 mass% as CaCO 3) or precipitated calcium carbonate (PCC). The process used an acid gas (H 2 S) to improve the aqueous dissolution of CaS, which is otherwise poorly soluble ...

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The process of claim 1, further comprising the step of performing one or more of dewatering, dispersion, or grinding, of the precipitated calcium carbonate product obtained in step (b) to obtain a precipitated calcium carbonate product having a D50 of between 0.35 and 0.4 …

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According to the process, limestone is burned at a high temperature to form calcium oxide and, thereafter, calcium carbonate is formed from calcium oxide in the presence of water and carbonate ions and the formed calcium carbonate is recovered. The formation of the carbonate may be performed by carbonating calcium oxide with carbon dioxide gas in the presence of water or water vapour, or by ...

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Precipitated calcium carbonate (PCC) is also used in papermaking as a coating and filler material. In conventional production of synthetic (i.e., precipitated) calcium carbonate, flue gas containing CO 2 is bubbled though a hydrated lime slurry (calcium hydroxide), from which calcium carbonate precipitates. By adjusting the precipitation ...

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Precipitated calcium carbonate production, synthesis and properties 59 al. (2008) and Lim et al. (2010) have investigated mineral carbonation with carbon dioxide gas. Teir et al. (2007) investigated dissolution properties of steelmaking slags in acetic acid for precipitated calcium carbonate production. Effect …

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process [46]. The formation of precipitated calcium carbonate (PCC) in pure ethanol as the solvent was possible without leaving Ca(OH) 2 as reac-tants; among them calcite was first precipitated from the carbonation in bulk solution as in the pure water, while the aragonite and vaterite might have been synthesized via local carbonation occurring ...

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The calcium carbonate was synthesized with the temperatures of 65, 100, 150, 200 and 234°C. The eggshell powder size was 29, 50, 80, 110, and 130 μm. The volume of water to mass of eggshell ...

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Milk of lime, precipitated calcium carbonate, morphology, particle size, carbonation. 1. Introduction Precipitated calcium carbonate (PCC) is a filler used in many applications, like papers, plastics, rubbers, paints, drugs and so on. Its high purity, well-ordered particle size and morphology makes it the white filler of choice.1 In paint ...

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Precipitated Calcium Carbonate. PCC stands for Precipitated Calcium Carbonate—also known as purified, refined or synthetic calcium carbonate. It has the same chemical formula as other types of calcium carbonate, such as limestone, marble and chalk: CaCO3. The calcium, carbon and oxygen atoms can arrange themselves in three different ways, to form three different calcium carbonate …

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Precipitated calcium carbonate is produced using the most economic process existing today. Limestone is converted into calcium oxide and carbon dioxide by means of calcination at temperatures in excess of 900°C. To ensure a high level of purity, the calcination process …

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A process for continuously producing precipitated calcium carbonate having a controllable particle diameter, in which nucleation and crystal growth are carried out in separate phases or phases. The size of the calcium carbonate particles is determined and/or controlled by the concentration of the calcium hydroxide suspension and by the ratio of CO 2 introduced to the volume of Ca(OH) 2 ...

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A process for the production of precipitated calcium carbonate. A slurry of calcium hydroxide is agitated in a pressurized reactor, and carbon dioxide is provided under pressure to the reactor to produce precipitated calcium carbonate at a high reaction rate. Carbon dioxide is utilized at a high efficiency. Solubilized calcium ions and carbonate ions react to produce a calcium carbonate ...

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The present invention provides a process for preparing a precipitated calcium carbonate product comprising the steps of: (a) preparing an aqueous suspension of precipitated calcium carbonate seeds by carbonating a suspension of Ca(OH) 2 in the presence of 0.005 to 0.030 moles of Sr, in the form of Sr(OH) 2, per mole of Ca(OH) 2, (b) dewatering and dispersing the precipitated calcium ...

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Formation Characteristics of Precipitated Calcium Carbonate by Carbonation Process 5 O2− ions which surrounding the Ca2+ ion than calcite and bonding with 9 O2− atoms. Therefore, calcium ions are easily captured than calcite by aragonite nuclei.

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Also, the design of a continuous test setup (total volume ∼75 L) is described, which enables quick process variations needed to adapt the system to the varying slag quality. Different precipitated calcium carbonate crystals (calcite and vaterite) are generated in different parts of the setup.

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