dicalcium silicate Chemical Properties

InChI

InChI=1S/2Ca.2O3Si/c;;2*1-4(2)3/q2*+2;2*-2

InChIKey

GGDIOEDJZLBCGA-UHFFFAOYSA-N

SMILES

[Ca+2].[Ca+2].[Si]([O-])([O-])=O.[Si]([O-])([O-])=O

EPA Substance Registry System

Silicic acid (H4SiO4), calcium salt (1:2) (10034-77-2)

Safety Information

TSCA 

TSCA listed

dicalcium silicate Usage And Synthesis

Chemical Properties

Dicalcium silicate crystallizes in four polymorphic modifications which are known under the designations α, α', β, and γ. The β modification is metastable at all temperatures. It is converted to the less dense γ modification at below 500 ℃. This conversion is the reason why a cement clinker rich in C2S may disintegrate at low cooling rates. In industrial clinkers, however, burnt above 1200 ℃, disintegration generally does not take place because the different high temperature modifications of C2S are stabilized by incorporation of, e.g., Al3+, Mg2+, P3+, Na+, K+ etc. The type of modification present in industrial clinkers additionally depends on the cooling rate. Commonly, C2S exists in its β modification besides the α and α' modifications.

General Description

Dicalcium silicate occurs when cement clinker is not completely saturated with calcium oxide. Pure dicalcium silicate melts congruently at 2130 ℃. In lime-rich raw mixes, C2S forms already at temperatures below 1000 ℃ by solid-state reaction. During the sintering process in the presence of a melt above 1250 ℃, C2S incorporates additional Ca2+, resulting in the formation of C3S. 

dicalcium silicate(10034-77-2)Related Product Information

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