Calcium silicate

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Calcium silicate
Image:Calcium silicate.png
General
Systematic name	Calcium silicate
Other names	silicic acid calcium salt, grammite, silene, micro-cell
Molecular formula	Ca₂SiO₄
Molar mass	172.2391 g/mol
Appearance	White or cream powder
CAS number	[1344-95-2]
Properties
Density and phase	? g/cm³, ?
Solubility in water	? g/100 ml (?°C)
Melting point	?°C (? K)
Boiling point	?°C (? K)
Acidity (pK_a)	?
Basicity (pK_b)	?
Structure
Molecular shape	?
Crystal structure	?
Hazards
MSDS	External MSDS
Main hazards	Irritant
NFPA 704
Flash point	?°C
R/S statement	R: ? S: ?
RTECS number	?
Related compounds
Other anions	?
Other cations	?
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) Infobox disclaimer and references

Calcium silicate is a white powder with the chemical formula Ca₂SiO₄. It has a low bulk density and high physical water absorption. It is used as an anti-caking agent and an antacid. A white free-flowing powder derived from limestone and diatomaceous earth, calcium silicate has no known adverse effects to health. It is used in roads, insulation and roof tiles.

1 High temperature insulation
2 Passive fire protection
3 Calcium silicate in the steel industry
4 As a product of sealants
5 See also

[edit] High temperature insulation

Industrial grade piping and equipment insulation is often fabricated from calcium silicate. Its fabrication is a routine part of the curriculum for insulation apprentices. Calcium silicate competes in these realms against rockwool as well as proprietary insulation solids, such as perlite mixtures and vermiculite bonded with sodium silicate.

[edit] Passive fire protection

Circuit integrity fireproofing of cable trays in Lingen/Ems, Germany using calcium silicate board system qualified to DIN 4102. Contractor: Signum, Bissendorf, Germany. Other methods for exterior protection of electrical circuits include boards made of sodium silicate bonded and pressed vermiculite and flexible wraps made of ceramic fibre and rockwool. One may also use ceramic fibre wraps treated with endothermic materials, provided strict bounding is ensured for all installed configurations, regardless of the product.

One of the most successful materials in fireproofing in Europe is calcium silicate. Where North Americans use spray fireproofing plasters, Europeans are more likely to use cladding made of calcium silicate. Calcium silicate is easily damaged by water. Therefore, silicone treated sheets are available to fabricators to mitigate potential harm from high humidity or general presence of water. Fabricators and installers of calcium silicate in passive fire protection often also install firestops.

[edit] Calcium silicate in the steel industry

It is also the remains of when molten iron is made from iron ore and calcium carbonate to produce slag in a blast furnace.

[edit] As a product of sealants

When sodium silicate is applied as a sealant to cured concrete or the shells of fresh eggs, it chemically reacts with calcium hydroxide or carbonate to form calcium silicate, sealing pores with a relatively impermiable material.