sulphate de calcium

Traductions

• anglais

  Date : 1983

  Définition

  A grayish-white heavy powder, which occurs in both anhydrous (CaSO₄) and hydrated (CaSO₄.2H₂O) forms, the latter being known as gypsum. It is found in nature in many localities and is also a by-product of many chemical reactions.
  
  A white salt know best in the hydrated forms, gypsum and plaster of Paris but also found as the anhydrous mineral anhrydrite.

  Notes :

  The anhydrous product is used to control the setting rate of Portland cement, as a weighting agent in paper sizes, and for coating textile products. It is also a neutralizing agent in soil conditioning. The hydrated form (gypsum) has the property of quickly setting to a hard solid in the presence of water; it is the chief component of plasters and cements, such as plaster of Paris, which is the hemihydrate, CaSO₄.1/2H₂=. It has also recently been developed as a commercial source of sulfur.
  
  It is obtained as a by-product in chemical pocesses, and used in its anhydrous form chiefly in keene's cement, in composite pigments, as a filler (as in paper), and as a drying agent.

  Termes :

  1. calcium sulfate
  2. calcium sulphate