Sodium sulphate

摘要

THE SODIUM SULPHATE market is unusual among industrial minerals in that the natural product competes on a level playing field with synthetically produced material. In most of the natural production sites, sodium sulphate is derived from the mining of thenardite (Na_2SO_4) or precipitation/evaporation from brines to form mirabilite salt (Na_2SO_4.l OH_2O, also called Glauber's salt). The formation of deposits is temperature dependent as below 32.4 deg C, more hydrous mirabilite will form from sodium sulphate brine but above this point the anhydrous form, thenardite is formed. Synthetic sodium sulphate is derived from a wide range of complex industrial chemical processes including sodium dichromate manufacture, rayon fibre spinning, speciality silica production, battery recycling, and a number of others.