Sorel cement

Sorel cement (also known as magnesia cement or magnesium oxychloride) is a non-hydraulic cement first produced by the French chemist Stanislas Sorel in 1867.[1]

In fact, in 1855, before working with magnesium compounds, Stanislas Sorel first developed a two-component cement by mixing zinc oxide powder with a solution of zinc chloride.[2][3] In a few minutes he obtained a dense material harder than limestone.

Only a decade later, Sorel replaced zinc with magnesium in his formula and also obtained a cement with similar favorable properties. This new type of cement was stronger and more elastic than Portland cement, and therefore exhibited a more resilient behavior when submitted to shocks. The material could be easily molded like plaster when freshly prepared, or machined on a lathe after setting and hardening. It was very hard, could be easily bound to many different types of materials (good adhesive properties), and colored with pigments. Therefore, it was used to make mosaics and to mimic marble. After mixing with cotton crushed in powder, it was also used as a surrogate material for ivory to fabricate billiard balls resistant to shock. [4]

Sorel cement is a mixture of magnesium oxide (burnt magnesia) with magnesium chloride with the approximate chemical formula Mg4Cl2(OH)6(H2O)8, or MgCl2·3Mg(OH)2·8H2O, corresponding to a weight ratio of 2.5–3.5 parts MgO to one part MgCl2.[5]

Quite surprisingly, much more recently, another chemist, Charles A. Sorrell (1977, 1980) – whose family name sounds quite similar to that of Stanislas Sorel – also studied the topic and published works on the same family of oxychloride compounds based on zinc and magnesium, just as Sorel had done about 100 years before. The zinc oxychloride cement is prepared from zinc oxide and zinc chloride instead of the magnesium compounds.[6][7]

  1. ^ Sorel Stanislas (1867). "Sur un nouveau ciment magnésien". Comptes Rendus Hebdomadaires des Séances de l'Académie des Sciences, volume 65, pages 102–104.
  2. ^ Sorel Stanislas (1856). Procédé pour la formation d'un ciment très-solide par l'action d'un chlorure sur l'oxyde de zinc. Bulletin de la Société d'Encouragement pour l'Industrie Nationale, 55, 51–53.
  3. ^ Souchu, Philippe (2012-04-18). "Le ciment Sorel". Site documentaire du Lerm. Retrieved 2020-07-08.
  4. ^ Chevalier, Michel (1868). "Exposition Universelle de 1867 à Paris. Rapports du Jury international, Tome dixième, Groupe VI, Arts Usuels – Classes 65 – Section I, Chapitre 3 – Matériaux artificiels, § 5 – Ciment d'oxychlorure de magnésium, 80–83". archive.org/. Imprimerie Administrative de Paul Dupont, Paris. Retrieved 2020-07-08.
  5. ^ Holleman, A. F.; Wiberg, E. (2001). "Inorganic Chemistry". Academic Press, San Diego. ISBN 0-12-352651-5.
  6. ^ Sorrell, Charles A. (1977). "Suggested chemistry of zinc oxychloride cements". Journal of the American Ceramic Society. 60 (5–6): 217–220. doi:10.1111/j.1151-2916.1977.tb14109.x. ISSN 0002-7820.
  7. ^ Urwongse, Ladawan; Sorrell, Charles A. (1980). "The system MgO-MgCl2-H2O at 23 °C". Journal of the American Ceramic Society. 63 (9–10): 501–504. doi:10.1111/j.1151-2916.1980.tb10752.x. ISSN 0002-7820.