• Title/Summary/Keyword: calcium carbonate

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Development of Hybrid Calcium Carbonate for High Loading Paper (I) - Manufacture and Application of Hybrid Calcium Carbonate - (고충전지 제조를 위한 하이브리드 탄산칼슘 충전제의 개발 (I) - 하이브리드 탄산칼슘의 제조 및 이용 -)

  • Jung, Jae Kwon;Seo, Yung Bum
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.47 no.4
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    • pp.30-37
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    • 2015
  • Needs for high ash loading in printing paper increase as green house gas (GHG) emission regulation becomes more stricter and pressure of lowering paper production cost increases. To meet the needs, a new type of filler was developed. The mixture of ground calcium carbonate (GCC) and calcium oxide was pre-floccuated with polyelectrolyte and further treated with carbon dioxide to form new calcium carbonate between GCCs. The final products were called as hybrid calcium carbonate (HCC), and its properties were compared to the GCC and the pre-flocculated GCC. Results showed increase in tensile, smoothness, opacity, and bulk for HCC.

Quality Characteristics of Soy Ice Creams as Affected by Enzyme Hydrolysis Times and Added Calciums (효소처리시간과 칼슘의 종류를 달리한 칼슘강화 콩아이스크림의 품질특성)

  • 김지영;이숙영
    • Korean journal of food and cookery science
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    • v.19 no.2
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    • pp.216-222
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    • 2003
  • The effects of hydrolysis times and calcium source additions (calcium lactate, calcium carbonate), on the qualify characteristics of soy ice cream prepared with soy protein isolate(SPI), were studied. Increasing the hydrolysis time decreased the viscosity and overrun of soy ice creams, but increased the melt-down property. The addition of calcium lactate increased the viscosity of the soy ice cream mix, but no changes were observed from the calcium carbonate addition. The overrun of calcium lactate samples was higher than on addition of calcium carbonate. The addition of calcium lactate and calcium carbonate resulted in decreased melt-down properties, although these effects were more evident in the calcium lactate samples. However, calcium carbonate addition resulted in higher scores in the overall quality of the soy ice creams. In conclusion, better soy ice cream could be prepared by treating the SPI with Flavorzyme for 50 min, along with calcium fortification in the form of calcium carbonate.

A Brief review of Aragonite Precipitated Calcium Carbonate (PCC) Synthesis Methods and Its Applications

  • Ramakrishna, Chilakala;Thenepalli, Thriveni;Ahn, Ji Whan
    • Korean Chemical Engineering Research
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    • v.55 no.4
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    • pp.443-455
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    • 2017
  • This article provides an exclusive overview of the synthesized aragonite precipitated calcium carbonate and its applications in various fields. The last decade has seen a steady increase in the number of publications describing the synthesis, characterization and applications of calcium carbonate morphologies. Mainly, two kinds of processes have been developed for the synthesis of aragonite precipitated calcium carbonate under controlled temperature, concentrations and aging, and the final product is single-phase needle-like aragonite precipitated calcium carbonate formed. This review is mainly focused on the history of developed methods for synthesizing aragonite PCC, crystal growth mechanisms and carbonation kinetics. Carbonation is an economic, simple and ecofriendly process. Aragonite PCC is a new kind of functional filler in the paper and plastic industries, nowadays; aragonite PCC synthesis is the most exciting and important industrial application due to numerous attractive properties. This paper describes the aragonite PCC synthetic approaches and discusses some properties and applications.

Non-isothermal Behavior of Calcium Carbonate (탄산칼슘의 비등온 열적거동)

  • Sohn, Yong-Un;Lim, Jae-Won;Choi, Good-Sun
    • Journal of Powder Materials
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    • v.16 no.3
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    • pp.167-172
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    • 2009
  • This study has been carried out to investigate the non-isothermal behaviors and kinetic parameter of calcium carbonate by different thermal analysis methods. At the heating rate of $10^{\circ}C$/min, the onset calcination temperature, the peak and final temperatures of calcium carbonate were $612^{\circ}C$, $748^{\circ}C$, and $890^{\circ}C$ respectively. As the heating rate of the calcium carbonate increased from $5^{\circ}C$/min to $20^{\circ}C$/min, the peak temperature increased from $719^{\circ}C$ to $782^{\circ}C$. The activation energies of the calcium carbonate calculated by the methods of Kissinger and Freeman-Carroll were 40.15 kcal/mol and 43.47 kcal/mol, respectively.

Histologic observation of regenerated bone in human intraosseous lesion following guided tissue regeneration with calcium carbonate implant and autogenous bone graft (Calcium carbonate 및 자가골 이식술을 동반한 조직유도재생술후 생검을 통한 재생골의 조직학적 관찰)

  • Lee, Yong-Moo;Han, Soo-Boo;Um, Heung-Sik;Kim, Dang-Kyoon
    • Journal of Periodontal and Implant Science
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    • v.28 no.2
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    • pp.263-273
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    • 1998
  • For histologic observation of the regenerated bone following guided tissue regeneration (GTR) using ePTFE membranes with calcium carbonate implant and autogenous bone graft, biopsies were collected from 2 patients during 5-year-postoperative surgical reentry. In both combined cases with guided tissue regeneration in conjunction with calcium carbonate implant and autogenous bone graft, significant bone fill and gain in probing attachment level was observed. In histologic examination, specimen in GTR case with calcium carbonate grafting was composed of a dense bone containing vascular channel with lamellar structure and viable bone cells in lacunae, however considerable calcium carbonate particles remained unresorbed and isolated from regenerated bone by the dense cellular and fibrous connective tissue. No formative cells could be seen in contact with remained calcium carbonate particles. In GTR case with autogenous bone grafting, specimen show was composed of a dense lamellar bone containing vascular channel, which showed normal alveolar bone architectures. The present observation indicate that guided tissue regeneration in conjunction with grafting, especially autogenous bone graft, has highly osteogenic potential, however resorbable calcium carbonate granules were not completely resorbed at 5 year postimplantation.

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Characteristics of Gaeryangmerou Wine deacidified by Calcium Carbonate (탄산칼슘 처리에 의한 개량머루주의 감산 특성)

  • Kim, Chan-Woo;Jeon, Jin-A;Kang, Ji-Eun;Choi, Han-Seok;Yeo, Soo-Hwan;Jeong, Seok-Tae
    • Journal of the East Asian Society of Dietary Life
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    • v.26 no.6
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    • pp.559-564
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    • 2016
  • We investigated the effect of calcium carbonate on the quality of wine obtained from Gaeryangmerou (Vitis. spp.), grapes, which are commonly used in wine making in Korea. Alcoholic fermentation was carried out at $25^{\circ}C$, for 7 days in the presence of 0.1%, 0.2%, and 0.3% calcium carbonate. As calcium carbonate concentration increased, the pH of wine increased, while its total acid content and redness decreased. Calcium carbonate treatment during precipitation and aging is more effective than during fermentation. Concentrations of alcohol, total anthocyanin, polyphenol, and tannin showed no significant differences between controls and deacidified groups. Tartaric and malic acids were found to be the major acids in Gaeryangmerou wine. Calcium carbonate reduced total acidity by precipitating tartaric acid. In the sensory evaluation of the acidity, and overall acceptability, wine treated with 0.1% calcium carbonate was the best. Higher calcium carbonate concentration, was associated with greater reduction in total wine acidity. However, it is necessary to maintain the calcium carbonate concentration within 0.1% since excessive amounts of calcium carbonate can have a negative effect on wine quality.

Synthesis and Crystallization of Amorphous Calcium Carbonate by Gas-Liquid Reaction of System Ca($OH_2 O$)-$H_2$-$CO_2$ (Ca($OH_2$)-$H_2 O$-$CO_2$계의 기액반응으로부터 비정질 탄산칼슘의 합성 및 결정화)

  • Im, Jae-Seok;Kim, Ga-Yeon;Im, Goeng
    • The Journal of Engineering Research
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    • v.5 no.1
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    • pp.73-87
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    • 2004
  • The synthesis and crystallization of amorphous calcium carbonate($CaCO_3$.$nH_2 O$) obtained from gas-liquid reaction between aqueous solution of calcium hydroxide and carbon dioxide at 15~$50^{\circ}C$ are investigated by electrical conductometry, XRD and TEM. The results are as follows: The initial reaction products prior to the formation of precipitated calcium carbonate is amorphous calcium carbonate. The electrical conductivity values in the slurry are decreased during the formation of amorphous calcium carbonate which covers particle surface of calcium hydroxide and retard the dissolution of calcium hydroxide into the solution. that amorphous calcium carbonate is unstable in the aqueous solution and crystallizes finally to calcite by the through-solution reaction. While amorphous calcium carbonate crystallizes into chain-like calcite, the conductivity values are recovered rapidly and the apparent viscosity of slurry containing higher concentration of calcium hydroxide increase. At below pH 9.5, chain-like calcite separates into individual particles to form precipitated calcium carbonate. The formation and synthetic temperature range of amorphous calcium carbonate is most suitable a primary decreasing step(a-step) at $15^{\circ}C$ in the electrical conductometry.

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Stability of Pre-treated Fillers for High Loaded Printing Paper (고충전 인쇄용지 제조를 위한 중질 탄산칼슘 전처리 기술의 안정성에 관한 연구)

  • Seo, Yung Bum;Choi, Jin Sung;Ji, Sung Gil
    • Korean Chemical Engineering Research
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    • v.55 no.1
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    • pp.1-6
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    • 2017
  • More addition of calcium carbonate in printing paper allows savings of the wood fibers and the drying energy. Pre-flocculation of GCC (ground calcium carbonate) using functional polymers was known as the best available technology to make high loaded paper until now, and it allowed less reduction of the paper essential properties such as tensile strength and smoothness at higher GCC content. However, pre-flocculated GCC became unstable in size under the continued agitation in the mill. Therefore, pre-flocculation method was modified in such a way that the in-situ calcium carbonate was formed between the GCC particles of the pre-flocculated GCC, and the resultant became more stable in size, which we named as HCC (hybrid calcium carbonate). HCC turned out to make high tensile strength and smoothness as much as the pre-flocculated GCC and gave much better size stability against stirring. Furthermore, HCC gave high bulk that pre-flocculation could not make.

Effect of chemical concentrations on strength and crystal size of biocemented sand

  • Choi, Sun-Gyu;Chu, Jian;Kwon, Tae-Hyuk
    • Geomechanics and Engineering
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    • v.17 no.5
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    • pp.465-473
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    • 2019
  • Biocementation due to the microbially induced calcium carbonate precipitation (MICP) process is a potential technique that can be used for soil improvement. However, the effect of biocementation may be affected by many factors, including nutrient concentration, bacterial strains, injection strategy, temperature, pH, and soil type. This study investigates mainly the effect of chemical concentration on the formation of calcium carbonate (e.g., quantity, size, and crystalline structure) and unconfined compressive strength (UCS) using different treatment time and chemical concentration in the biotreatment. Two chemical concentrations (0.5 and 1.0 M) and three different treatment times (2, 4, and 8 cycles) were studied. The effect of chemical concentrations on the treatment was also examined by making the total amount of chemicals injected to be the same, but using different times of treatment and chemical concentrations (8 cycles for 0.50 M and 4 cycles for 1.00 M). The UCS and CCC were measured and scanning electron microscopy (SEM) analysis was carried out. The SEM images revealed that the sizes of calcium carbonate crystals increased with an increase in chemical concentrations. The UCS values resulting from the treatments using low concentration were slightly greater than those from the treatments using high concentration, given the CCC to be more or less the same. This trend can be attributed to the size of the precipitated crystals, in which the cementation efficiency increases as the crystal size decreases, for a given CCC. Furthermore, in the high concentration treatment, two mineral types of calcium carbonate were precipitated, namely, calcite and amorphous calcium carbonate (ACC). As the crystal shape and morphology of ACC differ from those of calcite, the bonding provided by ACC can be weaker than that provided by calcite. As a result, the conditions of calcium carbonate were affected by test key factors and eventually, contributed to the UCS values.

Development of Hybrid Calcium Carbonate for High Loading Paper (II) - Comparison with GCC - (고충전지 제조를 위한 하이브리드 탄산칼슘 충전제의 개발 (II) - 중질탄산칼슘과 비교 -)

  • Jung, Jae Kwon;Seo, Yung Bum
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.47 no.4
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    • pp.76-80
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    • 2015
  • In filler loaded paper, the size of the filler affects its strength, optical and surface properties. As the size of the filler increases, tensile strength and bulk usually increases, opacity decreases, and smoothness becomes worse. Pre-flocculation of GCC (grounded calcium carbonate) makes large diameter flocs at aqueous medium that consists of multiple GCC particles, but they collapse to 2-dimensional shape in dried paper and makes low bulk paper. The hybrid calcium carbonate (HCC) that was made by in-situ $CaCO_3$ formation between GCC in aqueous medium made high bulk paper without harming tensile strength, bulk, opacity, and smoothness. The GCC that has equivalent size as HCC failed to make high opacity and smoothness as much as HCC.