Effect of FeSO4.7H2O and SnCl2.2H2O added as Chromium (VI) Reducers in Ordinary Portland Cement
نویسندگان
چکیده
The paper compared the effect of additives such as FeSO4.7H2O and SnCl2.2H2O on reduction of water soluble Cr(VI), in ordinary Portland cement (43 grades). The determination of water soluble Cr(VI) from cement samples was precisely conducted by DPC-Spectrophotometer technique. The compressive strength testing of the cement mortar samples was carried out. In addition, hydration properties of cement paste (with and without additives) are reported in this paper. Hydration products were also studied in detail by TGA, SEM and XRD. Tin chloride was found to be the most efficient additive for reducing Cr(VI) in cement. XRD confirmed two phases such as monocarbonate and Friedel’s salt were formed during cement hydration in the presence of tin chloride but not confirmed the presence of calcium hydroxo-stannate. These studies showed significant retardation in early days hydration.
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