Magnesium heptasulfate

Magnesium sulfate heptahydrate (molecular formula MgSO4.7H2O), also known as sulphur, bitter salt, cathartic salt and cathartic salt, is white or colorless acicular or oblique columnar crystals, odorless, cool and slightly bitter, molecular weight: 246.47, specific gravity 1.68, soluble in water, slightly soluble in ethanol and glycerol, soluble in its own crystalline water at 67.5 C. When decomposed by heat, the crystalline water losing the tetramolecule is at 70 and 80 degrees Celsius. It loses all crystalline water to anhydrous substance at about 200 C. It is easy to weathering into powder in air (drying). When heated, it gradually removes crystalline water and turns into anhydrous magnesium sulfate. This product does not contain any toxic impurities. Magnesium sulfate heptahydrate is easier to weigh than anhydrous magnesium sulfate because it is not easy to dissolve, and is convenient for quantitative control in industry. Mainly used in fertilizer, leather making, printing and dyeing, catalysts, paper making, plastics, porcelain, pigments, matches, explosives and fireproof materials manufacturing. It can be used for printing and dyeing thin cotton cloth and silk, as weighting agent of cotton silk and filler of kapok products, and as cathartic salt in medicine.