Non-stoichiometric hydrated magnesium-doped calcium carbonate precipitation in ethanol

The effect of Mg2+ on the precipitation pathway of CaCO3 in absolute ethanol has been studied to investigate the role of ion solvation in the crystallization process.

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The role of magnetic iron oxide nanoparticles in the bacterially induced calcium carbonate precipitation

Applied Microbiology and Biotechnology ◽

10.1007/s00253-018-8860-5 ◽

2018 ◽

Vol 102 (8) ◽

pp. 3595-3606 ◽

Cited By ~ 18

Author(s):

Mostafa Seifan ◽

Alireza Ebrahiminezhad ◽

Younes Ghasemi ◽

Ali Khajeh Samani ◽

Aydin Berenjian

Keyword(s):

Iron Oxide ◽

Calcium Carbonate ◽

Iron Oxide Nanoparticles ◽

Oxide Nanoparticles ◽

Carbonate Precipitation ◽

Calcium Carbonate Precipitation ◽

Magnetic Iron Oxide Nanoparticles ◽

Magnetic Iron Oxide

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Calcite seed-assisted microbial induced carbonate precipitation (MICP) and its potential in biocementation

10.1101/2020.07.17.206516 ◽

2020 ◽

Author(s):

Jennifer Zehner ◽

Anja Røyne ◽

Pawel Sikorski

Keyword(s):

Calcium Carbonate ◽

Crystallization Process ◽

Biological Process ◽

Precipitation Process ◽

Carbonate Precipitation ◽

Amorphous Calcium Carbonate ◽

Calcium Carbonate Precipitation ◽

Mineral Precipitation ◽

Solid Materials ◽

Significant Difference

Microbial-induced calcium carbonate precipitation (MICP) is a biological process inducing biomineralization of CaCO3. This can be used to form a solid, concrete-like material. To be able to use MICP successfully for producing solid materials, it is important to understand the formation process of the material in detail. It is well known, that crystallization surfaces can influence the precipitation process. Therefore, we present in this contribution a systematic study investigating the influence of calcite seeds on the MICP processes. We focus on the pH changes during the crystallization process measured with absorption spectroscopy and on the optical density (OD) signal to analyze the precipitation process. Furthermore, optical microscopy was used to visualize the precipitation processes in the sample and connect them to changes in pH and OD. We show that there is a significant difference in the pH evolution between samples with and without calcite seeds present and that the shape of the pH evolution and the changes in OD can give detailed information about the mineral precipitation and transformations. In the presented experiments we show that amorphous calcium carbonate (ACC) can also precipitate in the presence of initial calcite seeds, which can have consequences for consolidated MICP materials.

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Role of calcium carbonate precipitation in lake metabolism

10.2172/12513673 ◽

1974 ◽

Author(s):

W. Sedgefield White

Keyword(s):

Calcium Carbonate ◽

Carbonate Precipitation ◽

Calcium Carbonate Precipitation ◽

Lake Metabolism

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Role of Na-Montmorillonite on Microbially Induced Calcium Carbonate Precipitation

Molecules ◽

10.3390/molecules26206211 ◽

2021 ◽

Vol 26 (20) ◽

pp. 6211

Author(s):

Guowang Tang ◽

Cangqin Jia ◽

Guihe Wang ◽

Peizhi Yu ◽

Haonan Zhang

Keyword(s):

Calcium Carbonate ◽

Sandy Soil ◽

Carbonate Precipitation ◽

Soil Consolidation ◽

X Ray Diffraction ◽

Calcium Carbonate Precipitation ◽

X Ray ◽

Significant Attention ◽

Previous Reaction

The use of additives has generated significant attention due to their extensive application in the microbially induced calcium carbonate precipitation (MICP) process. This study aims to discuss the effects of Na-montmorillonite (Na-MMT) on CaCO3 crystallization and sandy soil consolidation through the MICP process. Compared with the traditional MICP method, a larger amount of CaCO3 precipitate was obtained. Moreover, the reaction of Ca2+ ions was accelerated, and bacteria were absorbed by a small amount of Na-MMT. Meanwhile, an increase in the total cementing solution (TCS) was not conducive to the previous reaction. This problem was solved by conducting the reaction with Na-MMT. The polymorphs and morphologies of the CaCO3 precipitates were tested by using X-ray diffraction and scanning electron microscopy. Further, when Na-MMT was used, the morphology of CaCO3 changed from an individual precipitate to agglomerations of the precipitate. Compared to the experiments without Na-MMT in the MICP process, the addition of Na-MMT significantly reduced the hydraulic conductivity (HC) of sandy soil consolidated.

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