POTASSIUM OLEATE SULFONATE OPA (POTASSIUM OLEATE SULFONATE). Potassium Oleate Sulfonate. OPA is an anionic surfactant with very good wetting and low foam.Potassium Oleate – properties. Potassium Oleate is the name used in the international INCI system and is also the chemical name of the potassium salt of oleic acid. Potassium Oleate is a potassium salt of both oleic acid and fatty acid. POTASSIUM OLEATE SULFONATE OPA is a salt because it is the product of an acid and a base. POTASSIUM OLEATE SULFONATE OPA Long carbon with a carboxyl group end