Sulfater

Sulfater are compounds containing the sulfate group, SO4^2-, and include both inorganic salts and organic esters of sulfuric acid. The sulfate ion features sulfur in a +6 oxidation state bonded to four oxygens in a tetrahedral arrangement. The term sulfater is the plural form in several languages; in English, sulfates is common.

In salts, sulfates form ionic compounds with a wide range of cations. Solubility varies: many alkali metal sulfates are readily soluble in water, some alkaline earth sulfates are also soluble, while others are sparingly soluble (such as calcium sulfate) or essentially insoluble (as with barium sulfate). Sulfate esters, such as alkyl sulfates, are widely used as surfactants in detergents and personal care products.

Natural occurrence includes minerals such as gypsum (calcium sulfate dihydrate) and anhydrite (calcium sulfate), as well as barite (barium sulfate). Sulfates form through weathering and oxidation of sulfide minerals and are common in evaporite deposits. They are also found dissolved in seawater and freshwater systems.

Uses span several industries. Sodium sulfate has played a historical role in the sulfate process for papermaking and in glass manufacture. Calcium sulfate and magnesium sulfate have medical and construction applications (plaster, drywall, baths), while organic sulfates are important as surfactants in cleaning products.

Biological and environmental aspects: sulfate is a nutrient for many plants and microorganisms, which assimilate it for growth. Some microbes reduce sulfate to sulfide as part of their metabolism. In the environment, sulfates influence water chemistry, soil health, and corrosion, and may originate from natural sources or industrial activities.