Sorel cement

Sorel cement (also known as Sorel concrete ) is developed by the Frenchman Stanislas Sorel in the 50s and 60s of the 19th century, acid-base cement. Acid acts as an aqueous solution of magnesium chloride, caustic calcined magnesite as the base ( magnesium oxide, MgO). Depending on the reactivity of the magnesium oxide used occurs within minutes or even several hours later to a hardening of the mixture:

5 MgO MgCl2 13 H2O → 5 Mg (OH ) 2.MgCl2.8H2O

The resulting compound is a magnesium oxychloride.

Use

Residential and industrial

Sorel cement is used for the production of industrial flooring and grinding and polishing stones for marble industry. Its advantages include the very rapid development of strength and high ultimate strength to its disadvantages, the leachability of the chlorine from the set cement due to water ingress.

In German -speaking countries, such floor coverings are called magnesia or Magnesitbeläge. Another advantage is, inter alia, that - in contrast to cement-based screeds - can be laid completely seamless. A variant of the magnesite screeds are known as " stone wood " flooring known. They were mainly in the post-war period much in housing - used - but also for light duty floors in the commercial sector. This stone wood coverings are also made of Magnesitbinder / magnesia cement and also contain significant amounts of wood flour ( sawdust) as a filler. Stone Wood floors are warm to the touch and comfortable to walk, they have a certain elasticity.

A significant disadvantage of all Magnesitbeläge - not only of stone wood - is the low water resistance. With moisture, the binder begins to swell and can involve large areas detached from the base. In addition, should - be avoided contact with sensitive against corrosion metals - because of the chlorine contained in the binder.

Assurance of atomic camps

This cement is used in the Asse mine to create flow barriers there. It even dosing and mixing plants were built near them. Normal building materials from cement are decomposed by salts or salt- containing solutions over time. Sorel concrete is especially resistant to potassium salts which prevail there.