What is hydroxyl number?

Hydroxyl number is a measure of the amount of hydroxyl groups in a chemical compound. It is expressed as the amount of potassium hydroxide (KOH) in milligrams needed to neutralize the hydroxyl groups in one gram of the compound.

The hydroxyl number is used to determine the average molecular weight of a compound as well as its degree of hydrophilicity (water-loving). Compounds with high hydroxyl numbers are typically more soluble in water and have better wetting properties.

The hydroxyl number is commonly used in the analysis of oils, fats, waxes and other organic compounds. It is also an important parameter in the production of polyols, which are widely used in the manufacture of polyurethane foams, coatings, adhesives and other products.

The hydroxyl number can be determined by various methods including titration, spectroscopy and chromatography.