Sulphonic acid

Sulphonic acid (also spelled sulfonic acid) refers to a class of organic compounds with the general formula RSO2OH, where R represents an organic group. Sulphonic acids are among the most important organo sulphur compounds in nature.

Structure and properties

Sulphonic acids have a sulphur atom bonded to a carbon atom of a hydrocarbon and bonded also to three oxygen atoms, one of which has been attached by a coordinate bond to a hydrogen atom. They are strong acids. Sulphonic acids and their salts and esters are called sulphonates.

Production

Sulphonic acids are typically prepared by the direct sulphonation of hydrocarbons. The process involves the reaction of a suitable hydrocarbon with sulphuric acid. Other methods include the oxidation of sulphides or the hydrolysis of sulfonyl chlorides.

Applications

Sulphonic acids and their derivatives are widely used in the manufacture of detergents, dyes, and pharmaceuticals. They also serve as intermediates in many chemical synthesis processes.

Health and safety

Exposure to sulphonic acids can cause irritation to the skin and eyes. Ingestion or inhalation can lead to serious health effects. Therefore, appropriate safety measures should be taken while handling these chemicals.

See also

• Sulphuric acid
• Organic chemistry
• Sulphonation