Sulphonic acid is a type of organic acid with the general formula R-SO₃H, where ‘R’ represents an organic group. It is a strong acid, often a million times stronger than a typical carboxylic acid. Its key properties and wide range of applications make it a fundamental compound in various industries.

key properties
- Chemical Formula: R-SO₃H
- Appearance: Typically a colorless to pale yellow liquid or crystalline solid.
- Acidity: Strong acid due to the electron-withdrawing nature of the sulfonyl group.
- Solubility: Highly soluble in water and other polar organic solvents.
- Stability: Generally stable at high temperatures.
Applications
- Detergents and Surfactants: It is a primary ingredient in the production of household and industrial detergents, as its derivatives, like Linear Alkyl Benzene Sulphonic Acid (LABSA), are excellent cleaning and foaming agents.
- Chemical Manufacturing: Used as an acid catalyst in various organic reactions and in the production of synthetic fibers, dyes, and pharmaceuticals.
- Water Treatment: Sulphonic acid-based groups are a key component in ion-exchange resins used for water softening and purification.
- Metal Plating: Specific types, such as methanesulfonic acid, are used in the metal finishing and plating industry.
Safety Precautions
- Corrosive Nature: Sulphonic acid is a corrosive substance that can cause severe burns to the skin and eyes. Inhalation can cause respiratory irritation.
- Handling: Always handle with extreme care in a well-ventilated area. Personal protective equipment (PPE), including gloves, goggles, and a face shield, is essential.
- Storage: Store in a cool, dry place away from incompatible materials such as strong bases and oxidizing agents.
