Turpentine (which is also called spirit of turpentine, oil of turpentine, terebenthine, terebenthene, terebinthine and, colloquially, turps)[2] is a fluid obtained by the distillation of resin harvested from living trees, mainly pines. Principally used as a specialized solvent, it is also a source of material for organic syntheses.
Substitutes include white spirit or other petroleum distillates – although the constituent chemicals are very different.[4]
Etymology
The word turpentine derives (via French and Latin) from the Greek word τερεβινθίνη terebinthine, in turn the feminine form (to conform to the feminine gender of the Greek word, which means 'resin') of an adjective (τερεβίνθινος) derived from the Greek noun (τερέβινθος) for the terebinth tree.[5]
"Herty system" in use on turpentine trees in Northern Florida, circa 1936Chipping a turpentine tree in Georgia (US), circa 1906–20"Cat face" on a pine treeTurpentine distillery at Manlyn, North Carolina
To tap into the sap producing layers of the tree, harvesters used a series of hacks to remove the pine bark. Once debarked, pine trees secrete crude turpentine (oleoresin) onto the surface of the wound as a protective measure to seal the opening, resist exposure to micro-organisms and insects, and prevent vital sap loss. Harvesters wounded trees in V-shaped streaks down the length of the trunks to channel the crude turpentine into containers. It was then collected and processed into spirits of turpentine. Crude turpentine yield may be increased by as much as 40% by applying paraquatherbicides to the exposed wood.[10]
The V-shaped cuts are called "catfaces" for their resemblance to a cat's whiskers. These marks on a pine tree indicate it was used to collect resin for turpentine production.[11]
Crude turpentine collected from the trees may be evaporated by steam distillation in a copper still. Molten rosin remains in the still bottoms after turpentine has been distilled out.[10] Such turpentine is called gum turpentine.[13] The term gum turpentine may also refer to crude turpentine, which may cause some confusion.
Turpentine may alternatively be extracted from destructive distillation of pine wood,[3] such as shredded pine stumps, roots, and slash, using the light end of the heavy naphtha fraction (boiling between 90 and 115 °C or 195 and 240 °F) from a crude oil refinery. Such turpentine is called wood turpentine. Multi-stage counter-current extraction is commonly used so fresh naphtha first contacts wood leached in previous stages and naphtha laden with turpentine from previous stages contacts fresh wood before vacuum distillation to recover naphtha from the turpentine. Leached wood is steamed for additional naphtha recovery prior to burning for energy recovery.[14]
Sulfate turpentine
When producing chemical wood pulp from pines or other coniferous trees, sulfate turpentine may be condensed from the gas generated in Kraft process pulp digesters. The average yield of crude sulfate turpentine is 5–10 kg/t pulp.[15] Unless burned at the mill for energy production, sulfate turpentine may require additional treatment measures to remove traces of sulfur compounds.[16]
Industrial and other end uses
Solvent
As a solvent, turpentine is used for thinning oil-based paints, for producing varnishes, and as a raw material for the chemical industry. Its use as a solvent in industrialized nations has largely been replaced by the much cheaper turpentine substitutes obtained from petroleum such as white spirit. A solution of turpentine and beeswax or carnauba wax has long been used as a furniture wax.
Lighting
Spirits of turpentine, called camphine, was burned in lamps with glass chimneys in the 1830s through the 1860s. Turpentine blended with grain alcohol was known as burning fluid. Both were used as domestic lamp fuels, gradually replacing whale oil, until kerosene, gas lighting and electric lights began to predominate.
Source of organic compounds
Turpentine is also used as a source of raw materials in the synthesis of fragrant chemical compounds. Commercially used camphor, linalool, alpha-terpineol, and geraniol are all usually produced from alpha-pinene and beta-pinene, which are two of the chief chemical components of turpentine. These pinenes are separated and purified by distillation. The mixture of diterpenes and triterpenes that is left as residue after turpentine distillation is sold as rosin.
Folk medicine
Turpentine and petroleum distillates such as coal oil and kerosene, were used in folk medicine for abrasions and wounds, as a treatment for lice, and when mixed with animal fat, as a chest rub or inhaler for nasal and throat ailments.[17][18]Vickschest rubs still contain turpentine in their formulations, although not as an active ingredient.[19]
Turpentine enemas, a very harsh purgative, had formerly been used for stubborn constipation or impaction.[23] They were also given punitively to political dissenters in post-independence Argentina.[24]
Niche uses
Turpentine is also added to many cleaning and sanitary products due to its antiseptic properties and its "clean scent".
In early 19th-century America, spirits of turpentine (camphine) was burned in lamps as a cheap alternative to whale oil. It produced a bright light but had a strong odour.[25] Camphine and burning fluid (a mix of alcohol and turpentine) served as the dominant lamp fuels replacing whale oil until the advent of kerosene, electric lights and gas lighting.[26]
Honda motorcycles, first manufactured in 1946, ran on a blend of gasoline and turpentine, due to the scarcity of gasoline in Japan following World War II.[27]
In his book If Only They Could Talk, veterinarian and author James Herriot describes the use of the reaction of turpentine with resublimed iodine to "drive the iodine into the tissue", or perhaps just impress the watching customer with a spectacular treatment (a dense cloud of purple smoke).[28]
Turpentine was added extensively into gin during the Gin Craze.[29]
As an organic solvent, turpentine's vapour can irritate the skin and eyes, damage the lungs and respiratory system, as well as the central nervous system when inhaled, and cause damage to the renal system when ingested, among other things.[30] Ingestion can cause burning sensations, abdominal pain, nausea, vomiting, confusion, convulsions, diarrhea, tachycardia, unconsciousness, respiratory failure,[31] and chemical pneumonia.
^Stenius, Per, ed. (2000). "2". Forest Products Chemistry. Papermaking Science and Technology. Vol. 3. Finland: Fapet Oy : Published in cooperation with the Finnish Paper Engineers' Association and TAPPI. pp. 73–76. ISBN952-5216-03-9.
^"Surviving 'The Spanish Lady' (Spanish flu)". CBC News. 2003-04-10. Event occurs at 03:20. Archived from the original on 2020-08-07. Retrieved 2018-12-29. A turpentine and hot water, and [wring hot towels out of there], and put it on their chest and back. --Elsie Miller (nee Smith)
^"Turpentine enema". Biology-Online Dictionary. Biology-Online. 7 October 2019. Archived from the original on 2019-04-21. Retrieved 2019-12-26.
^"Ribbons and Rituals". In "Problems in Modern Latin American History". Ed. Chasteen and Wood. Oxford, UK: Scholarly Resources, 2005. p. 97, ISBN 9781442218598 and 9781442218604
