Sodium Hydroxide

Strong alkali used for alkalinity and pH control in treatment systems.

The same chemistry as our caustic soda flakes, listed separately because plants that dose it continuously order it as a process chemical rather than a cleaning one. It is the standard reagent for holding treated water within its target pH band and for adding alkalinity where a coagulant has consumed it — alum and PAC both drive pH down as they work, and something has to bring it back.

• —Continuous pH correction in treatment plants
• —Restoring alkalinity consumed by coagulant dosing
• —Effluent neutralisation before discharge
• —Industrial process pH control

Severely corrosive to skin and eyes. Full protective equipment required. Always add to water rather than the reverse, as the dissolution reaction is strongly exothermic. Store separately from acids — accidental mixing reacts violently.

Sodium Hydroxide is also sold and searched for as Caustic soda, NaOH, Lye and Sodium hydrate.