KOH 48% vs 90%: which grade should you choose?

KOH 48% and KOH 90% are two commercial forms of the same chemical (potassium hydroxide): 48% is a ready-to-use aqueous solution, while 90% is a solid flake or granule. The choice depends on the trade-off between ease of dosing and water content versus shipping cost: plants that want liquid metering and are not sensitive to freight per active ingredient prefer 48%, while those that want no added water or need to ship a high active concentration over long distances prefer 90%.

Same chemical, two forms

Potassium hydroxide (KOH, caustic potash) is a strong base used in liquid soaps, fertilizers, food additives, battery electrolytes and various chemical syntheses. Two common grades are traded: an aqueous solution of about 48% KOH and a solid flake/granule of at least 90% KOH. The active chemical is identical; the difference lies in physical form, water content and the resulting logistics and handling.

KOH 48% vs 90% comparison

Which one should you choose?

KOH 48% (liquid) is usually preferred where dosing automation runs on liquids, where continuous processes want no dissolving step, and where powder/flake handling is considered risky. The solution is easily pumped and generates no dust.

KOH 90% (solid flake) is advantageous where you want to cut freight and storage cost per active ingredient, where formulations should not gain extra water, and where long shelf life or long-distance transport is needed. The solid form carries more KOH in less volume.