Naphtha

Naphtha (/ˈnæpθə/ or /ˈnæfθə/) is a flammable liquid hydrocarbon mixture. Mixtures labelled naphtha have been produced from natural gas condensates, petroleum distillates, and the distillation of coal tar and peat. In different industries and regions naptha may also be crude oil or refined products such as kerosene. Mineral spirits, also historically known as "naptha", are not the same chemical.

Etymology

The word naphtha is from Latin and Ancient Greek (νάφθα), derived from Middle Persian naft ("wet", "naphtha"),[1][2] from Old Persian 𐎴𐎳𐎫. In Ancient Greek, it was used to refer to any sort of petroleum or pitch. The term entered Semitic languages as well in antiquity: It appears in Arabic as نَفْط nafṭ ("petroleum"), in Syriac as ܢܰܦܬܳܐ naftā, and in Hebrew as נֵפְט neft.

The book of II Maccabees tells how a "thick water" was put on a sacrifice at the time of Nehemiah and when the sun shone it caught fire. It adds that "those around Nehemiah termed this 'Nephthar', which means Purification, but it is called Nephthaei by the many [literally hoi polloi]."[3]

Naphtha is the root of the word naphthalene. The second syllable of "naphtha" can also be recognised in phthalate.

It also enters the word napalm, a contraction of the "na" of naphthenic acid and "palm" of palmitic acid, originally made from a mixture of naphthenic acid combined with aluminium and magnesium salts of palmitic acid.

In older usage, "naphtha" simply meant crude oil, but this usage is now obsolete in English. It was also used for mineral spirits (also known as "Stoddard Solvent"), the "naptha" originally in Fels Naptha laundry soap. The Ukrainian and Belarusian word нафта (lit. nafta), Lithuanian, Latvian and Estonian "nafta", the Russian word нефть (lit. neft') and the Persian naft (نفت) mean "crude oil". Also, in Albania, Bosnia and Herzegovina, Bulgaria, Croatia, Italy, Serbia, Slovenia, nafta (нафта in Cyrillic) is colloquially used to indicate diesel fuel and crude oil. In the Czech Republic and Slovakia, nafta was historically used for both diesel fuel and crude oil, but its use for crude oil is now obsolete[4] and it generally indicates diesel fuel. In Bulgarian, nafta means diesel fuel, while neft, as well as petrol (петрол in Cyrillic), means crude oil. Nafta is also used in Argentina, Paraguay and Uruguay to refer to gasoline/petrol.[5] In Poland, the word nafta means kerosene.[6] In Flemish, the word naft is used colloquially for gasoline.[7]

There is a conjecture that the Greek word naphtha came from the Indo-Iranian god name Apam Napat, which occurs in Vedic and in Avestic;[8] the name means "grandson of (the) waters", and the Vedas describe him as fire emerging from water, perhaps inspired by a burning seepage of natural gas.

Types

Various qualifiers have been added to the term "naphtha" by different sources in an effort to make it more specific:

One source[9] distinguishes by boiling point:

Light naphtha is the fraction boiling between 30 °C and 90 °C and consists of molecules with 5–6 carbon atoms. Heavy naphtha boils between 90 °C and 200 °C and consists of molecules with 6–12 carbon atoms.

Another source[10] differentiates light and heavy comments on the hydrocarbon structure, but offers a less precise dividing line:

Light [is] a mixture consisting mainly of straight-chained and cyclic aliphatic hydrocarbons having from five to six carbon atoms per molecule. Heavy [is] a mixture consisting mainly of straight-chained and cyclic aliphatic hydrocarbons having from seven to nine carbon atoms per molecule.

Both of these are useful definitions, but they are incompatible with one another. These terms are also sufficiently broad that they are not widely useful.

Health and safety considerations

The material safety data sheets (MSDSs) from various naphtha vendors are also indicative of the non-specific nature of the product and reflect the considerations due for a flammable mixture of hydrocarbons: flammability, carcinogenicity, skin and airway irritation, etc.[11][12][13][14]

Humans can be exposed to naphtha in the workplace by breathing it in, swallowing it, skin contact, and eye contact. The US Occupational Safety and Health Administration (OSHA) has set the permissible exposure limit for naphtha exposure in the workplace as 100 ppm (400 mg/m3) over an 8-hour workday. The US National Institute for Occupational Safety and Health (NIOSH) has set a recommended exposure limit (REL) of 100 ppm (400 mg/m3) over an 8-hour workday. At levels of 1000 ppm, 10% of the lower explosive limit, naphtha is immediately dangerous to life and health.[15]

See also

References

  1. Christian Gizewski (Berlin Institute of Technology). "Persisches Erbe im Griechischen, Lateinischen, Arabischen, Türkischen und in verschiedenen heutigen europäischen Sprachen (Persian Heritage in Greek, Latin, Arabic, Turkic and Various Modern European Languages)". Technische Universität Berlin. Retrieved 2010-02-28.
  2. David Neil MacKenzie (1971). A Concise Pahlavi Dictionary. Oxford University Press. p. 57. ISBN 978-1-934768-59-4.
  3. 2 Maccabees 1:36
  4. "Slovenské slovníky". Slovnik.juls.savba.sk. Retrieved 2015-10-26.
  5. Pedro Mairal (2012). El año del desierto. Stockcero, Inc. pp. 71–. ISBN 978-1-934768-59-4.
  6. Andrey Taranov (23 October 2013). Polish vocabulary for English speakers - 7000 words. BoD - Books on Demand. pp. 98–. ISBN 978-1-78071-417-2.
  7. Michael G. Clyne (1992). Pluricentric Languages: Differing Norms in Different Nations. Walter de Gruyter. pp. 85–. ISBN 978-3-11-012855-0.
  8. 3・4・5歳児の保育おたよりイラスト決定版: かわいいイラストがたっぷり!. Books.google.co.uk. p. 12. Retrieved 2015-10-26.
  9. Prestvic, Rune; Kjell Moljord; Knut Grande; Anders Holmen (2004). "Compositional analysis of naphtha and reformate". Catalytic naphtha reforming. USA: CRC Press. p. 2. Retrieved 2010-02-03.
  10. "Chemistry of Hazardous Materials, Third Edition", Meyer, E., Prentice Hall, 1998, page 458.
  11. "Petroleum Ether". Hazard.com. 1998-04-21. Retrieved 2015-10-26.
  12. "Material Safety Data Sheet : Shellite" (PDF). Recochem.com.au. Retrieved 2015-10-26.
  13. "Material Safety Data Sheet : Ronsonol Lighter Fuel" (PDF). Cooperbooth.com. Retrieved 2015-10-26.
  14. "NAFAA". NAFAA. Retrieved 2015-10-26.
  15. "CDC - NIOSH Pocket Guide to Chemical Hazards - Naphtha (coal tar)". www.cdc.gov. Retrieved 2015-11-27.
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