Solidification of Cr Ions by Ettringite at Different Sulfate Concentrations

被引：0

作者：

Wang X. ^{[1
,2
]}

Cui S. ^{[1
]}

Yan B. ^{[2
]}

Wang L. ^{[2
]}

Zhang J. ^{[2
]}

机构：

[1] College of Materials Science and Engineering, Beijing University of Technology, Beijing

[2] China Building Materials Academy, Beijing

来源：

Jianzhu Cailiao Xuebao/Journal of Building Materials | 2019年 / 22卷 / 06期

关键词：

Construction; Cr ion; Ettringite; SO[!sub]4[!/sub] [!sup]2-[!/sup; Solidification;

D O I：

10.3969/j.issn.1007-9629.2019.06.007

中图分类号：

学科分类号：

摘要：

The solidification of ettringite on the chromium ions with different valence states and species under the condition of different sulfate concentrations were investigated by means of XRD, IR analysis, DSC, SEM, ICP and other method. The results showed that the ettringite solidification rate for the low dosage(0.5%) of chromium ions with different valence and species was add up to 85% or more. The solidification rate of ettringite to Cr(Ⅲ) changed little, while the solidification rate to Cr(Ⅵ) 28d decreased to 38.6% when the dosage of chromium ions increased to 2.0%. The solidification ability of ettringite to Cr(Ⅵ) was improved when the concentrations of SO4 2- ions were low in the hydrated liquid phase. No matter what concentration of SO4 2- ions was in the hydrated liquid phase, Cr(Ⅲ) and Cr(Ⅵ) had a different effects on the crystal structure and morphology of ettringite, and that of Cr(Ⅲ) was more obvious. The effect of Cr ions on ettringite crystal morphology was also different. When the concentrations of SO4 2- ions were low in the hydrated liquid phase, the doping of Cr(Ⅲ) could obviously promote the growth and development of ettringite crystal in the c-axis direction, and improve the crystallization degree and thermal stability of ettringite to a certain extent. © 2019, Editorial Department of Journal of Building Materials. All right reserved.

引用

页码：878 / 885

页数：7

共 20 条

[1] Taylor H.F.M., Cement Chemistry, pp. 176-181, (1997)
[2] Bhishan P., Stephen D., Kinrad E., Et al., Effects of carbonation on the leachability and compressive strength of cement-solidified and geopolymer-solidified synthetic metal wastes, Journal of Environmental Management, 101, 30, pp. 59-67, (2012)
[3] Vysvaril M., Bayer P., Immobilization of heavy metals in natural zeolite-blended cement pastes, Procedia Engineering, 151, pp. 162-169, (2016)
[4] Binglin G., Keiko S., Tsuyoshi H., Selenite and selenate uptaken in ettringite: Immobilization mechanisms, coordination chemistry, and insights from structure, Cement and Concrete Research, 100, pp. 166-175, (2017)
[5] Klemmw A., Bhatty J.I., Fixation of heavy metals as oxyan-ion-substituted ettringites, pp. 9-10, (2002)
[6] Li S., Guo S.L., Huang X., Research on characteristics of heavy metals(As, Cd, Zn) in coal from southwest China and prevention method by using modified calcium-based materials, Fuel, 186, 15, pp. 714-725, (2016)
[7] Wieslawa N.-W., Barbara T., The properties of cement pastes and mortars processed with some heavy metal nitrates containing solutions, Procedia Engineering, 108, pp. 72-79, (2015)
[8] Gougar M.L.D., Scheetz B.E., Roy D.M., Ettringite and C-S-H Portland cement phases for waste iron immobilization: A review, Waste Management, 16, 4, pp. 295-303, (1996)
[9] Zbignie W., Giergiczn Y., Krol A., Immobilization of heavy metals(Pb, Cu, Cr, Zn, Cd, Mn) in the mineral additions containing concrete composites, Hazardous Terials, 160, 30, pp. 247-255, (2008)
[10] Poellmann H., Auer S.T., Kuzal H.-J., Solid solution of ettringites: Part Ⅱ: Incorporation of B(OH)4 and CrO4 2- in 3CaO•Al2O3•3CaSO4•32H2O, Cement and Concrete Research, 23, 1, pp. 422-430, (1993)

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