Naphthenic acid by a general formula CH O, where "n" indicates the carbon number and "z" specifies a homologous series. The "z" is equal to 0 for saturated, acyclic acids and increases to 2 in monocyclic naphthenic acids, to 4 in bicyclic naphthenic acids, to 6 in tricyclic acids, and to 8 in tetracyclic acids. Salts of naphthenic acids, called naphthenates, are widely used as hydrophobic sources of metal ions in diverse applications.Aluminium salts of naphthenic acid and palmitic acid were combined during World War II to produce napalm. The word "napalm" is derived from the words naphthenic acid and palmitic acid.
Copper naphthenate adhesion promoters, lubricant additives, and catalysts where oil solubility is required. Naphthenic acid is a complex group of carboxylic acids with the general formula CHO where n indicates the carbon number and z specifies the hydrogen deficiency resulting from ring formation. Naphthenic acids occur naturally in crude oil at varying concentrations, and their composition varies with the crude oil composition and the conditions during refining. Crude oils with total acid number (TAN) as little as 0.5 mg KOH/g acid or petroleum fractions greater than about 1.0 mg KOH/g oil usually qualify as a high acid crude or oil. At the