Why in news?
The growing popularity of eco‑friendly cleaning products has led to renewed interest in how soaps and detergents are made and how they differ. Environmentally conscious consumers want products that clean effectively without harming water bodies.
What are soaps?
- Soaps are salts of fatty acids produced by reacting vegetable or animal fats with a strong alkali such as sodium hydroxide (caustic soda) or potassium hydroxide.
- Common oils used include coconut, palm, olive and soybean oils. After saponification, perfumes and colourants may be added.
- Soaps are biodegradable and work best in soft water. They form scum in hard water because of mineral reactions.
What are detergents?
- Detergents are synthetic cleansing agents derived mainly from petrochemicals. They contain surfactants that loosen dirt and grease.
- Typical ingredients include linear alkyl benzene sulphonate and sodium lauryl sulphate, along with builders like sodium carbonate or phosphates, enzymes, bleaches, dyes and fragrances.
- Detergents work well in both soft and hard water but some components can pollute rivers and harm aquatic life.
Manufacturing processes
- Soap making: Fats are hydrolysed into fatty acids and then reacted with a strong alkali. The resulting soap is dried, blended with additives and shaped into bars.
- Detergent making: Petrochemical feedstocks are sulphonated to create surfactants, neutralised with alkali, mixed with builders and additives, spray‑dried into powders or agglomerated into pellets and then packaged.
Environmental considerations
Soaps are generally biodegradable, whereas some detergent components can persist in water and contribute to pollution. Choosing products with fewer phosphates and opting for plant‑based surfactants can reduce environmental impact.