Caustic Potash

Product summary

A representative alkaline product manufactured through the electrolysis of potassium chloride solution


Strong alkaline product with acute toxicity and corrosivity.
It is a “hazardous substance” under the Poisonous and Deleterious Substances Control Act.

Generic name: potassium hydroxide
Chemical formula: KOH

(Reaction) KCl + H2O > KOH Caustic potash + 1/2H2 Hydrogen + 1/2Cl2 Chlorine

CSCL Number  1-369
Industrial Safety and Health Act Number  1-369
CAS NO  1310-58-3

Main uses

The manufacturing of all kinds of potassium chloride, soft soap, petrochemicals, optical glass, etc.


Liquid caustic potash (48%) comes in chemical tank trucks, drums (280kg) and plastic bags.

Please select to match your intended use.

Physical Properties

Caustic potash (liquid)Caustic potash (solid)
AppearanceChanging condition of concentration and
temperature may solidify from liquid state.
Solid (flakes)
Color Colorless and transparent White
Odor Odorless Odorless
Boiling point140°C1,320°C
Melting point No data available360°C
Density1.5g/cm3 (15°C)2.04g/cm3

Warnings for use

It is corrosive to eyes and skin, so always wear protective gear such as protective goggles, rubber gloves, and rubber boots.
It produces heat if diluting or neutralizing acid, so please add a small amount of potassium hydroxide liquid while stirring.
Never add water or acid into a concentrated solution of potassium hydroxide, because there is a danger of causing an explosive boil.


Phase diagram (taken from a graph of solidifying temperature per concentration)
*Please refer to the SDS for more detailed product information.

Production plant

■ AGC Inc. (Japan) Chiba Plant