Ligroin is the petroleum fraction consisting mostly of C7 and C8hydrocarbons and boiling in the range 90‒140 °C (194–284 °F). The fraction is also called heavy naphtha.[1][2] Ligroin is used as a laboratory solvent. Products under the name ligroin can have boiling ranges as low as 60‒80 °C and may be called light naphtha.[3]
The name ligroin (or ligroine or ligroïne) appeared as early as 1866.[note 1]
Ligroin is assigned the CAS Registry Number 8032-32-4, which is also applied to many other products, particularly the lower boiling ones, called petroleum spirit, petroleum ether and petroleum benzine.[3]
^The name "ligroin" was coined in the United States:
Heppe, G., ed. (1890). Klemens Merck's Warenlexikon für Handel, Industrie und Gewerbe [Klemens Merck's dictionary of commodities for commerce, industry, and trade] (in German). Leipzig, Germany: G. A. Gloeckner. p. 349. From p. 349: "Ligroine; der in Amerika erfundene Name für einen der flüchtigeren Teile des rohen Petroleums, … " (Ligroin: the name that was coined in America for one of the more volatile parts of crude petroleum, … )
Early use in English:
(Editorial staff) (24 October 1866). "Polytechnic Association of the American Institute". The American Artisan and Patent Record. 3: 389. From p. 389: "Dr. Van der Weyde then exhibited some samples of the products of distillation of tar, and a safety-lamp for burning the lighter hydro-carbons, which is mainly a reproduction of the "Ligroine" lamp invented and put into the market first by C. Schreiber in Munich (Bavaria), and described in the March number of Dingler's Polytechnic Journal."
Schafhäutl (1866). "Ueber die neue Li-gro-ine- oder Petroleum-Gaslampe" [On the new ligroin or petroleum gas lamp]. Dinglers Polytechnisches Journal (in German). 179: 472–475. From p. 474: "Das einzige Gefährliche ist die Aufbewahrung des Leuchtstoffes, der sogenannten Li-gro-ine selbst. Diese Naphta oder Li-gro-ine muß, wenn in großen Quantitäten vorhanden, in wohl verschlossenen Gefäßen aufbewahrt werden." (The one danger is the storage of the lamp fuel, the so-called "ligroin" itself. This naphtha or "ligroin" must, if present in large quantities, be stored in well sealed containers.)