zwavelzure

Zwavelzure, or sulfuric acid, is a colorless, highly viscous mineral acid with the chemical formula H2SO4. It is one of the most widely produced and used chemicals in industry, central to inorganic and industrial chemistry. Concentrated sulfuric acid is dense and highly hygroscopic, readily absorbing water from air and mixing with water exothermically. It is a strong diprotic acid; the first dissociation is complete in water and the second remains substantially strong, making the solution highly conductive and corrosive. At high concentrations it can act as a powerful dehydrating agent and can behave as an oxidizer under certain conditions.

Industrial production is dominated by the contact process. Sulfur is burned to form sulfur dioxide (SO2), which is oxidized to sulfur trioxide (SO3) over a vanadium oxide catalyst. The SO3 is absorbed in concentrated sulfuric acid to form oleum (H2SO4·SO3), which is then diluted to the desired strength. Historically, sulfuric acid was produced by the lead chamber process; the contact process now accounts for the vast majority of supply.

Uses of zwavelzure are broad. It is essential for producing phosphate fertilizers and is a key reagent in mineral processing, petroleum refining, and chemical synthesis. It is also used in metal pickling, paper pulping, and the manufacture of detergents and dyes. In lead-acid batteries, sulfuric acid provides the electrolyte. In the laboratory, diluted solutions serve as a versatile strong acid and dehydrating agent.

Safety and handling are critical due to its corrosivity. Concentrated sulfuric acid can cause severe burns to skin and eyes and releases harmful fumes. It reacts violently with water and organic materials; proper PPE, ventilation, and storage in corrosion-resistant containers are required. Accidental contact requires immediate rinsing with water and medical attention.