naphthenic, a. Chem.
(næfˈθiːnɪk)
[ad. F. naphténique (Markovnikov & Oglobine 1884, in Ann. de Chim. et de Physique II. 476), f. naphtène naphthene: see -ic.]
1. naphthenic acid: any of the carboxylic acids obtained in the refining of petroleum, esp. one derived from an alicyclic compound (as cyclohexane or cyclopentane); also, an unspecified mixture of such acids.
| 1894 Jrnl. Chem. Soc. LXVI. i. 532 The methyl salts of the lower natural naphthenic acids were prepared and fractionated with a view to isolate the methyl salt of heptanaphthenic acid (hexahydrobenzoic acid). 1932 Jrnl. Amer. Chem. Soc. LIV. 240 We observed that naphthenic acids are formed when linoleic acid is cracked under pressure. 1942 Chem. Rev. XXX. 100 The mixture of acids now known as naphthenic acid. 1946 S. B. Elliott Alkaline-Earth & Heavy-Metal Soaps ii. 33 Naphthenic acids..are the raw materials from which some of the most important soaps are manufactured. 1957 Van der Have & Verver Petroleum xiii. 383 The free naphthenic acids also find certain applications, for instance as wetting agents for the pigments used in printing inks and paints. 1966 McGraw-Hill Encycl. Chem. Technol. X. 47/2 Naphthenic acid production is about 16,000,000 lb annually. |
2. Of, pertaining to, or containing naphthenes.
| 1931 Engineering 2 Jan. 1/2 Cyclohexane, a hydrocarbon of the naphthenic series. 1969 Sci. Jrnl. Nov. 32/2 The basic structure of bitumen is that of clusters of naphthenic and aromatic rings... It is called a naphthenic crude oil. 1974 Sci. Amer. Dec. 7 (Advt.), Up to this point, the best traction drive lubricants were naphthenic oils. |
Hence ˈnaphthenate, any of the salts of a naphthenic acid, some of which are used as paint driers, as fungicides, and in lubricants.
| 1899 Jrnl. Chem. Soc. LXXVI. i. 423 (heading) Properties of naphthenates and their qualitative distinction from salts of fatty acids. 1924 Chem. Abstr. XVIII. 2688 Al naphthenate forms a transparent, colorless, and porous mass which can be powdered; it has a water-proofing action. 1942 Chem. Rev. XXX. 103 In the case of castor machine oils, where increased..viscosity..is desired, various naphthenates have been used. 1960 E. L. Delmar-Morgan Cruising Yacht Equipment & Navigation xiii. 158 It is usually possible to see when power kerosene is deteriorating, by the fact that it becomes bright green in colour, as a result of the formation of copper naphthenate formed by the interaction of the fuel and the metal of a copper or brass tank. 1973 Biol. Abstr. LV. 6965/2 Potassium naphthenate significantly increased the ascorbic acid content of green pods of bush bean plants. |