What it is
Strong alkali made with chlorine by electrolysis of salt. Used in soap, detergents, textiles, paper, alumina and water treatment.
Lye (about 32% / 48–50%)FlakesPrills / pearls
Where India produces it
Where imports come from
India makes more than it uses: production 3,926.6 thousand tonnes against consumption of 3,516.1 thousand tonnes in 2024-25 (DCPC).
- Australia
- Austria
- Bangladesh
- Belgium
- Canada
Rules before you buy or sell
- BIS QCO in force: caustic soda must carry the BIS mark to IS 252:2013 (Bureau of Indian Standards (Caustic Soda) Order, 2018, S.O. 1468(E), 3 Apr 2018). Imports also need a BIS licence.
- Sodium hydroxide is listed in Schedule 1 of the Manufacture, Storage and Import of Hazardous Chemical (MSIHC) Rules, 1989. Above the threshold quantities, a unit must notify authorities, keep safety data sheets and an on-site emergency plan.
Storage and handling
Corrosive. Store flakes in sealed bags in a dry place; lye in mild-steel or HDPE tanks. Keep away from acids and aluminium; wear goggles and gloves.
Businesses that use it
Bath Soap Manufacturing Unit →Laundry Soap Making →Detergent Cake (Washing Bar) →Liquid Detergent →Dupatta Colouring and Dyeing Unit →Cotton Yarn Dyeing (Hank and Package Dyeing) →Bleaching and Dyeing of Cotton Knitted Fabric (Job Work) →
Sources (4)
- Chemical and Petrochemical Statistics at a Glance 2025, Department of Chemicals & Petrochemicals (Tables 3, 5, 8, 10, 16, 17, 20, 28)
- Directory of Chemical & Petrochemical Units 2022-23 (large and medium units), Department of Chemicals & Petrochemicals · 2023
- BIS — Products under compulsory certification, Scheme-I (QCO list with amendment and rescind orders; page updated 24 Sep 2026) · 2026
- Manufacture, Storage and Import of Hazardous Chemical Rules, 1989 (as amended up to 2000), Schedule 1 — copy hosted by Inspectorate of Factories & Boilers, Goa · 1989