FMC manufactures caustic soda, the common name for sodium hydroxide (NaOH), in Green River, Wyoming. FMC's product is considered Chemical Grade caustic soda and is produced by reacting soda ash with lime. The product is available in bulk quantities as a 50% liquid solution.

Caustic soda is used as the primary strong base in the chemical industry. Applications include cleaning, detergent production, water treatment, oil drilling, fuel processing, pulp & paper manufacturing, biodiesel production, food preparation and more.