The rate and mechanism of polymorphic transformation of calcium carbonate in water

Ogino, Takeshi; Suzuki, Toshio; Sawada, Kiyoshi

doi:10.1016/0022-0248(90)90618-u

Cited by 110 publications

(94 citation statements)

References 32 publications

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“…The predominance of calcite relative to the other CaCO 3 polymorphs further supports this hypothesis. Indeed, in a supersaturated solution of Ca 21 and CO 3 22 , amorphous CaCO 3 precipitates first, then transforms to vaterite, and finally to calcite, which is the most thermodynamically stable CaCO 3 polymorph (Ogino et al, 1990). In the presence of Mg 21 , the formation of aragonite is favored at the expense of calcite.…”

Section: Discussionmentioning

confidence: 99%

Trichomes of Tobacco Excrete Zinc as Zinc-Substituted Calcium Carbonate and Other Zinc-Containing Compounds

et al. 2006

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(S.F., M.A.M.) Tobacco (Nicotiana tabacum L. cv Xanthi) plants were exposed to toxic levels of zinc (Zn). Zn exposure resulted in toxicity signs in plants, and these damages were partly reduced by a calcium (Ca) supplement. Confocal imaging of intracellular Zn using Zinquin showed that Zn was preferentially accumulated in trichomes. Exposure to Zn and Zn 1 Ca increased the trichome density and induced the production of Ca/Zn mineral grains on the head cells of trichomes. These grains were aggregates of submicrometer-sized crystals and poorly crystalline material and contained Ca as major element, along with subordinate amounts of Zn, manganese, potassium, chlorine, phosphorus, silicon, and magnesium. Micro x-ray diffraction revealed that the large majority of the grains were composed essentially of metal-substituted calcite (CaCO 3 ). CaCO 3 polymorphs (aragonite and vaterite) and CaC 2 O 4 (Ca oxalate) mono-and dihydrate also were identified, either as an admixture to calcite or in separate grains. Some grains did not diffract, although they contained Ca, suggesting the presence of amorphous form of Ca. The presence of Zn-substituted calcite was confirmed by Zn K-edge micro-extended x-ray absorption fine structure spectroscopy. Zn bound to organic compounds and Zn-containing silica and phosphate were also identified by this technique. The proportion of Zn-substituted calcite relative to the other species increased with Ca exposure. The production of Zn-containing biogenic calcite and other Zn compounds through the trichomes is a novel mechanism involved in Zn detoxification. This study illustrates the potential of laterally resolved x-ray synchrotron radiation techniques to study biomineralization and metal homeostasis processes in plants.Smoking of tobacco (Nicotiana tabacum) leaves is one of the principal routes of exposure to heavy metals. Metals contained in tobacco leaves originate from root uptake and transfer to the shoots and also from deposition of aerosol particles on the leaves (Fleisher and Parungo, 1974). Efforts have been made to minimize toxic metal contents in the leaves (LugonMoulin et al., 2004). However, this is not the case for counterfeit tobacco products, which contain higher concentrations of metals than their genuine equivalents (Stephens et al., 2005). Besides its primary application for leaf production, tobacco is also a candidate for phytoextraction. Although this plant species is not a hyperaccumulator, it has several advantages, including a high biomass, moderate soil requirements, fast growth rate, and ease of harvesting. For this particular application, research is conducted with the aim of enhancing metal accumulation in the shoots (Song et al., 2003).Little is known about the mechanisms of metals accumulation and detoxification in tobacco. The exposure of plants to high concentrations of metals generally induces a stress, whose visible symptoms include an inhibition of root elongation, a decrease in shoot growth, leaf chlorosis, and necrosis of the tissues. This stress is ge...

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Section: Discussionmentioning

confidence: 99%

Trichomes of Tobacco Excrete Zinc as Zinc-Substituted Calcium Carbonate and Other Zinc-Containing Compounds

et al. 2006

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“…There are three crystalline anhydrous CaCO 3 polymorphs 2 -calcite, aragonite, and vaterite, and amorphous anhydrous CaCO 3 is also known. The CaCO 3 polymorphs and their crystallization and transformation mechanisms are discussed in Carlson (1983), Cölfen (2003), Jiménez-López et al (2001), Kitamura (2001), Nissenbaum et al (2008), Ogino et al (1987Ogino et al ( , 1990, Perdikouri et al (2008), and the references therein. Crystals of calcite, aragonite, and vaterite are typically rhombohedral, acicular (needle-like), and polycrystalline spherical, respectively, in morphology.…”

Section: 2mentioning

confidence: 99%

Thermodynamic Data for Geochemical Modeling of Carbonate Reactions Associated with CO2 Sequestration – Literature Review

Krupka

Cantrell

McGrail

2010

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SummaryPermanent storage of anthropogenic CO 2 in deep geologic formations is being considered as a means to reduce the concentration of atmospheric CO 2 and thus its contribution to global climate change. To assure safe and effective geologic sequestration, numerous studies have been completed regarding the extent to which CO 2 migrates within geologic formations, and what physical and geochemical changes occur in these formations when CO 2 is injected. Sophisticated, computerized reservoir simulations are used as part of field site and laboratory CO 2 sequestration studies. These simulations use coupled multiphase flow-reactive chemical transport models and/or standalone (i.e., no coupled fluid transport) geochemical models to calculate gas solubility, aqueous complexation, reduction/oxidation (redox), and/or mineral solubility reactions related to CO 2 injection and sequestration.Thermodynamic data are critical inputs to modeling geochemical processes. The adequacy of thermodynamic data for carbonate compounds has been identified as an important data requirement for the successful application of these geochemical reaction models to CO 2 sequestration. Therefore, a review was completed of thermodynamic data for CO 2 gas and carbonate aqueous species and minerals present in published data compilations and databases used in geochemical reaction models. Published studies that describe mineralogical analyses from CO 2 sequestration field and natural analogue sites and laboratory studies were also reviewed to identify specific carbonate minerals that are important to CO 2 sequestration reactions and therefore require thermodynamic data.The results of the literature review (Section 5.0) indicate that an extensive thermodynamic database exists for CO 2 and CH 4 gases, carbonate aqueous species, and carbonate minerals. Values of ∆ f G 298° and/or log K r,298° are available for essentially all of these compounds. However, log K r,T° or heat capacity values at temperatures above 298 K exist for less than approximately one-third of these compounds. Because the temperatures of host formations that will be used for CO 2 injection and sequestration will be at temperatures in the range of 50ºC to 100ºC or greater, the lack of high-temperature thermodynamic values for key carbonate compounds, especially minerals, will impact the accuracy of some modeling calculations.In comparison to the available thermodynamic data for carbonate minerals, only a small number of carbonate minerals have been described in published studies as actually being present in the host rock formations at CO 2 injection test sites or natural analogue sites, reaction products of CO 2 injection/ intrusion into a host formation, or as mineral reactants or products of laboratory CO 2 fluid-rock and -mineral experiments. Except for a few carbonate solid-solution minerals (ferroan and magnesian carbonates and ferroan dolomite), thermodynamic data are available for the pure carbonate minerals identified in these natural analogue site and fluid-rock and -mineral...

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“…In the environment, ACC is thermodynamically unstable and rapidly transforms into vaterite and 250 then calcite (17). However, it is found as a stable compound in plants (e.g., cystoliths) and 251 animals (e.g., cuticle of crustaceans, spicules of ascidiae, granules in molluscs) (18).…”

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confidence: 99%

Chemical forms of calcium in Ca,Zn- and Ca,Cd-containing grains excreted by tobacco trichomes

Sarret¹,

Isaure²,

Marcus³

et al. 2007

Can. J. Chem.

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Tobacco (Nicotiana tabacum L. cv. Xanthi) plants exposed to toxic levels of zinc and cadmium excrete metals through their leaf trichomes (epidermal hairs) as Zn,Ca- and Cd,Ca-containing grains. Little is known about the nature and formation mechanism of these precipitates. The chemical, crystalline, and non-crystalline compositions of individual grains produced by tobacco were studied by scanning electron microscopy coupled with energy dispersive X-ray analysis (SEM-EDX), micro-X-ray diffraction (μXRD) and calcium K-edge micro X-ray absorption near edge structure (μXANES) spectroscopy. Zinc is predominantly incorporated in calcite, and cadmium in calcite and vaterite. Aragonite, which occurs occasionally, does not seem to contain trace metals. In addition to being precipitated in its three possible polymorphic forms, calcite, aragonite and vaterite, calcium also is speciated as amorphous CaCO3 and possibly organic Ca in some grains. Most often, a particular grain consists of two or more crystalline and non-crystalline phases. The observed variability of intra- and inter-grain elemental and phase composition suggests that this biomineralization process is not constrained by biological factors, but instead results from thermodynamically and kinetically controlled reactions. This study illustrates the potential of laterally resolved X-ray synchrotron radiation techniques (μXRD and μXANES) to study biomineralization and metal immobilization processes in plants

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The rate and mechanism of polymorphic transformation of calcium carbonate in water

Cited by 110 publications

References 32 publications

Trichomes of Tobacco Excrete Zinc as Zinc-Substituted Calcium Carbonate and Other Zinc-Containing Compounds

Trichomes of Tobacco Excrete Zinc as Zinc-Substituted Calcium Carbonate and Other Zinc-Containing Compounds

Thermodynamic Data for Geochemical Modeling of Carbonate Reactions Associated with CO2 Sequestration – Literature Review

Chemical forms of calcium in Ca,Zn- and Ca,Cd-containing grains excreted by tobacco trichomes

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