ettringite has been researched along with aluminum-sulfate* in 2 studies
2 other study(ies) available for ettringite and aluminum-sulfate
Article | Year |
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Ettringite and monosulfate formation to reduce alkalinity in reactions of alum-based water treatment residual with steel slag.
Aged steel slag has a potential use as a highly durable aggregate in roadway construction; however, its high capacity for creating alkaline leachates (pH > 12.4) poses a severe environmental risk. In batch and column leach tests, 10% alum-based water treatment residual (WTR) addition to aged steel slag resulted in a 67% decrease in acid neutralizing capacity of steel slag and leachate alkalinity, but this alkalinity mitigation effect was accompanied with markedly increases in dissolved Al concentrations in the leachates (<4.6 mM) compared to steel slag-only samples. Measurements of dissolved ions, saturation index evaluations, and results of geochemical modeling analysis indicated that ettringite and monosulfate formations were favored and that it is probably the responsible mechanism for the observed mitigation of alkalinity and Ca release under alkaline conditions. Topics: Alum Compounds; Industrial Waste; Minerals; Steel; Water Pollutants, Chemical; Water Purification | 2019 |
Characterization of hydration products of mineral trioxide aggregate.
To characterize the hydration products of white mineral trioxide aggregate (MTA).. Mineral trioxide aggregate, white Portland cement and bismuth oxide were evaluated using X-ray diffraction (XRD) analysis and Rietveld XRD. The cements were tested un-hydrated and after hydration and curing for 30 days at 37 degrees C. Analysis of hydrated cement leachate was performed weekly for five consecutive weeks from mixing using inductively coupled plasma atomic emission spectroscopy after which the cements were viewed under the scanning electron microscope to evaluate the cement microstructure. Quantitative energy dispersive analysis with X-ray was performed and atomic ratios were plotted.. Both Portland cement and MTA produced calcium silicate hydrate (C-S-H) and calcium hydroxide (CH) on hydration. The tricalcium aluminate levels were low for MTA which resulted in reduced production of ettringite and monosulphate. On hydration the bismuth level in the hydrated MTA decreased; bismuth oxide replaced the silica in the C-S-H and was leached out once the C-S-H decomposed with time. Both MTA and Portland cement released a high amount of calcium ions which decreased in amount over the 5-week period.. The hydration mechanism of MTA is different to that of Portland cement. In MTA the bismuth oxide is bound to the C-S-H and is leached out from the cement with time as the C-S-H decomposes. MTA produces a high proportion of calcium ions from CH a by-product of hydration and also by decomposition of C-S-H. The release of calcium ions reduces with time. Topics: Alum Compounds; Aluminum Compounds; Bismuth; Calcium Compounds; Calcium Hydroxide; Dental Cements; Drug Combinations; Hydrolysis; Microscopy, Electron, Scanning; Minerals; Oxides; Root Canal Filling Materials; Silicates; Spectroscopy, Electron Energy-Loss; X-Ray Diffraction | 2008 |