Sorel cement

After mixing with cotton crushed in powder, it was also used as a surrogate material for ivory to fabricate billiard balls resistant to shock.

[1] In the late 19th century, several attempts were made to determine the composition of the hardened Sorel's cement, but the results were not conclusive.

It also exhibits some elasticity, an interesting property increasing its capacity to resist shocks (better mechanical resilience), particularly useful for billiard balls.

[19] Prolonged exposure of Sorel cement to water leaches out the soluble MgCl2, leaving hydrated brucite Mg(OH)2 as the binding phase, which without absorption of CO2, can result in loss of strength.

[17] In use, Sorel cement is usually combined with filler materials such as gravel, sand, marble flour, asbestos, wood particles and expanded clays.

[20] The resistance of the cement to water can be improved with the use of additives such as phosphoric acid, soluble phosphates, fly ash, or silica.

Sorel cement is also studied as a candidate material for chemical buffers and engineered barriers (drift seals made of salt-concrete) for deep geological repositories of high-level nuclear waste in salt-rock formations (Waste Isolation Pilot Plant (WIPP) in New Mexico, USA; Asse II salt mine, Gorleben and Morsleben in Germany).

[21][22][23] Phase 5 of the magnesium oxychloride could be a useful complement, or replacement, for MgO (periclase) presently used as a CO2 getter in the WIPP disposal chambers to limit the solubility of minor actinides carbonate complexes, while establishing moderately alkaline conditions (pH: 8.5–9.5) still compatible with the undisturbed geochemical conditions initially prevailing in situ in the salt formations.

Moreover, as magnesium hydroxychloride is also a possible pH buffer in marine evaporite brines, Sorel cement is expected to less disturb initial in situ conditions prevailing in deep salts formations.

However, the chemical reactions that create the oxychlorides may not run to completion, leaving unreacted MgO particles and/or MgCl2 in pore solution.