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Castor oil

From Wikipedia, the free encyclopedia
For the fictional character from theThimble Theatrecomic strip, seeCastor Oyl.Not to be confused withCastoreum.
Castor beans
A bottle of castor oil

Castor oilis avegetable oilpressed fromcastor beans.[1] It is a colourless or pale yellow liquid with a distinct taste and odor. Itsboiling pointis 313 °C (595 °F) and itsdensityis 0.961 g/cm3.[2]It includes a mixture oftriglyceridesin which about 90% of fatty acids arericinoleates.Oleic acidandlinoleic acidare the other significant components.

Castor oil and its derivatives are used in the manufacturing ofsoaps,lubricants,hydraulic andbrake fluids,paints,dyes,coatings,inks,cold-resistantplastics,waxesand polishes,nylon,andperfumes.[3]

Etymology[edit]

The name probably comes from a confusion between theRicinusplant that produces it and another plant, theVitex agnus-castus.[4][5]An alternative etymology, though, suggests that it was used as a replacement forcastoreum.[6]

Composition[edit]

Structure of the major component of castor oil: triester of glycerol and ricinoleic acid

Castor oil is well known as a source ofricinoleic acid,amonounsaturated,18-carbonfatty acid.Among fatty acids, ricinoleic acid is unusual in that it has ahydroxylfunctional groupon the 12th carbon atom. This functional group causes ricinoleic acid (and castor oil) to be morepolarthan most fats. The chemical reactivity of the alcohol group also allows chemicalderivatizationthat is not possible with most other seed oils.

Because of its ricinoleic acid content, castor oil is a valuable chemical in feedstocks, commanding a higher price than other seed oils. As an example, in July 2007, Indian castor oil sold for aboutUS$0.90/kg ($0.41/lb),[citation needed]whereas U.S.soybean,sunflower,andcanolaoils sold for about $0.30/kg ($0.14/lb).[7]

Average composition of castor seed oil / fatty acids
Acid name Range Type
Ricinoleic acid 85–95 ω−9
Oleic acid 2–6 ω−9
Linoleic acid 1–5 ω−6
α-Linolenic acid 0.5–1 ω−3
Stearic acid 0.5–1 saturated
Palmitic acid 0.5–1 saturated
Dihydroxystearic acid 0.3–0.5 saturated
Others 0.2–0.5

Uses[edit]

Annually, 270,000–360,000 tonnes (600–800 million pounds) of castor oil are produced for a variety of uses.[3]

Human uses[edit]

Castor oil has been used orally to relieveconstipationor to evacuate thebowelbeforeintestinalsurgery.[8]Thelaxativeeffect of castor oil is attributed toricinoleic acid,which is produced byhydrolysisin thesmall intestine.[8]Use of castor oil for simple constipation is medically discouraged because it may cause violentdiarrhea.[8]

Food and preservative[edit]

In the food industry, food-grade castor oil is used in food additives, flavorings, candy (e.g.,polyglycerol polyricinoleateinchocolate),[9] as a mold inhibitor, and in packaging. Polyoxyethylated castor oil (e.g.,Kolliphor EL)[10]is also used in the food industries.[11]

InIndia,Pakistan,andNepal,food grains arepreservedby the application of castor oil. It stopsrice,wheat,andpulsesfrom rotting. For example, the legumepigeon peais commonly available coated in oil for extended storage.

Traditional medicine[edit]

Advertisement of castor oil as a medicine by Scott & Bowne Company, 19th century

Use of castor oil as a laxative is attested to in the c. 1550 BCEEbers Papyrus,[12]and was in use several centuries earlier.[13]

According to theAmerican Cancer Society,"available scientific evidence does not support claims that castor oil on the skin cures cancer or any other disease."[14]

Childbirth[edit]

Castor oil has been historically used toinduce laborin pregnant women. A 1984 study concluded "castor oil, which is more economical and convenient thanoxytocin,can be used safely and effectively to stimulate labor ".[15]Another trial concluded "research is needed to attempt to quantify the efficacy of castor oil as a cervical priming and induction agent".[16]Another comparison found "Women who receive castor oil have an increased likelihood of initiation of labor within 24 hours compared to women who receive no treatment. Castor oil use in pregnancy is underreported worldwide".[17]Castor oil may be effective in triggering contractions in "patients who are at or past theirdelivery datebut have not gone into labor ".[18]A 2022 meta-analysis published in an Iranian nursing and midwifery journal found "use of castor oil has positive effect on labor induction and increases the prevalence ofvaginal delivery.None of the studies considered in this meta-analysis reported any serious harmful effects for the use of castor oil ".[19]Diarrhea(with concomitant risk ofdehydration) is an expectedside effectof ingesting castor oil to induce labor.[19]

Punishment[edit]

Since children commonly strongly dislike the taste of castor oil, some parentspunished childrenwith a dose of it.[20][21]Physicians recommended against the practice because they did not want medicines associated with punishment.[22]

A heavy dose of castor oil could be used as a humiliating punishment for adults. Colonial officials used it in theBritish Raj(India) to deal with recalcitrant servants.[23] Belgian military officials prescribed heavy doses of castor oil inBelgian Congoas a punishment for being too sick to work.[24]

Castor oil was also a tool of punishment favored by theFalangistand laterFrancoist Spainduring and following theSpanish Civil War.[25] Its use as a form ofgendered violenceto repress women was especially prominent.[25][26] This began during the war whereNationalistforces would specifically target Republican-aligned women, both troops and civilians, who lived inRepublican-controlled areas.[25] The forced drinking of castor oil occurred alongside sexual assault, rape, torture and murder of these women.[25][27]

Its most notorious use as punishment came inFascist ItalyunderBenito Mussolini.It was a favorite tool used by theBlackshirtsto intimidate and humiliate their opponents.[28][29][30] Political dissidentswere force-fed large quantities of castor oil byfascistsquads so as to induce bouts of extreme diarrhea in the victims. This technique was said to have been originated byGabriele D'AnnunzioorItalo Balbo.[31]This form of torture was potentially deadly, as the administration of the castor oil was often combined withnightstickbeatings, especially to therear,so that the resulting diarrhea would not only lead to dangerous dehydration but alsoinfectthe open wounds from the beatings. However, even those victims who survived had to bear thehumiliationof the laxative effects resulting from excessive consumption of the oil.[32]

Emollient[edit]

Castor oil has been used incosmeticproducts included in creams and as amoisturizer.It is often combined withzinc oxideto form anemollientandastringent,zinc and castor oil cream, which is commonly used to treat infants fornappy rash.[33] [34]

Industrial uses[edit]

Coatings[edit]

Castor oil is used as a biobasedpolyolin thepolyurethaneindustry. The average functionality (number ofhydroxylgroups per triglyceride molecule) of castor oil is 2.7, so it is widely used as a rigid polyol and in coatings.[1] One particular use is in a polyurethane concrete where a castor-oil emulsion is reacted with an isocyanate (usually polymericmethylene diphenyl diisocyanate) and acementandconstruction aggregate.This is applied fairly thickly as a slurry, which is self-levelling. This base is usually further coated with other systems to build a resilient floor.[35]

Castor oil is not adrying oil,meaning that it has a low reactivity with air compared with oils such aslinseed oilandtung oil.However, dehydration of castor oil yields linoleic acids, which do have drying properties.[1] In this process, the OH group on the ricinoleic acid along with a hydrogen from the next carbon atom are removed, forming a double bond which then has oxidative cross-linking properties and yields the drying oil. It is considered a vital raw material.[36]

Precursor to industrial chemicals[edit]

Castor oil can react with other materials to produce other chemical compounds that have numerous applications.[37] [38] [39] [40] Transesterificationfollowed by steam cracking givesundecylenic acid,a precursor to specialized polymernylon 11,andheptanal,a component in fragrances.[41] Breakdown of castor oil in strong base gives2-octanol,both a fragrance component and a specialized solvent, and thedicarboxylic acidsebacic acid.Hydrogenation of castor oil saturates the alkenes, giving a waxy lubricant.[1] Castor oil may be epoxidized by reacting the OH groups withepichlorohydrinto make thetriglycidyl ether of castor oilwhich is useful in epoxy technology.[42] This is available commercially as Heloxy 505.[43]

The production oflithium greaseconsumes a significant amount of castor oil.Hydrogenationandsaponificationof castor oil yields 12-hydroxystearic acid, which is then reacted withlithium hydroxideorlithium carbonateto give high-performance lubricant grease.[44]

Since it has a relatively highdielectric constant(4.7), highly refined and dried castor oil is sometimes used as adielectric fluidwithin high-performance, high-voltagecapacitors.

Lubrication[edit]

Castor oil advertisement from The Aerial Age Weekly in 1921

Vegetable oils such as castor oil are typically unattractive alternatives topetroleum-derivedlubricantsbecause of their pooroxidativestability.[45][46]Castor oil has better low-temperatureviscosityproperties and high-temperature lubrication than most vegetable oils, making it useful as a lubricant injet,diesel,and racing engines.[47]The viscosity of castor oil at 10 °C is 2,420centipoise,[48]but it tends to form gums in a short time, so its usefulness is limited to engines that are regularly rebuilt, such as racing engines. Lubricant companyCastroltook its name from castor oil.

Castor oil has been suggested as a lubricant forbicycle pumpsbecause it does not degrade natural rubber seals.[49]

Early aviation and aeromodelling[edit]

World War I aviationrotary enginesused castor oil as a primary lubricant, mixed with the fuel

Castor oil was the preferred lubricant forrotary engines,such as theGnome engineafter that engine's widespread adoption for aviation in Europe in 1909. It was used almost universally in rotary-engined Allied aircraft inWorld War I.Germany had to make do with inferiorersatzoil for its rotary engines, which resulted in poor reliability.[50][51][52]

Themethanol-fueled, two-cycle,glow-plug enginesused for aeromodelling, since their adoption bymodel airplanehobbyists in the 1940s, have used varying percentages of castor oil as lubricants. It is highly resistant to degradation when the engine has its fuel-air mixture leaned for maximum engine speed. Gummy residues can still be a problem for aeromodelling powerplants lubricated with castor oil, however, usually requiring eventual replacement ofball bearingswhen the residue accumulates within the engine's bearing races. One British manufacturer ofsleeve valvedfour-cycle model engines has stated the "varnish" created by using castor oil in small percentages can improve the pneumatic seal of the sleeve valve, improving such an engine's performance over time.

Turkey red oil[edit]

Turkey red oil, also called sulphonated (or sulfated) castor oil, is made by addingsulfuric acidto vegetable oils, most notably castor oil.[53]It was the first syntheticdetergentafter ordinarysoap.It is used in formulatinglubricants,softeners, anddyeing assistants.[53]

Biodiesel[edit]

Castor oil, like currently less expensive vegetable oils, can be used as feedstock in the production ofbiodiesel.The resulting fuel is superior for cold winters, because of its exceptionally lowcloud pointandpour point.[54]

Initiatives to grow more castor for energy production, in preference to other oil crops, are motivated by social considerations. Tropical subsistence farmers would gain a cash crop.[55]

Safety[edit]

The castor seed containsricin,a toxiclectin.Heating during the oil extraction process denatures and deactivates the lectin. Harvesting castor beans, though, may not be without risk.[56]The International Castor Oil Association FAQ document states that castor beans contain an allergenic compound called CB1A. This chemical is described as being virtually nontoxic, but has the capacity to affect people with hypersensitivity. The allergen may be neutralized by treatment with a variety of alkaline agents. The allergen is not present in the castor oil itself.[57]

See also[edit]

References[edit]

  1. ^abcdThomas, Alfred (2005). "Fats and Fatty Oils".Ullmann's Encyclopedia of Industrial Chemistry.Weinheim: Wiley-VCH.doi:10.1002/14356007.a10_173.ISBN978-3527306732.
  2. ^Aldrich Handbook of Fine Chemicals and Laboratory Equipment.Sigma-Aldrich. 2003.[full citation needed]
  3. ^abMutlu, H; Meier, MAR (January 2010). "Castor oil as a renewable resource for the chemical industry".European Journal of Lipid Science and Technology.112(1): 10–30.doi:10.1002/ejlt.200900138.
  4. ^"The Castor Bean: A Plant Named After A Tick".Wayne's Word: An Online Textbook of Natural History. March 1999. Archived fromthe originalon 2021-11-15.Retrieved2020-04-26.
  5. ^Irene Jacob, "Ricinus Communis — The Miracle Tree through Four Thousand Years",The Healing Past: Pharmaceuticals in the Biblical and Rabbinic World,ed. Irene and Walter Jacob (Brill, 1993), 81-93.
  6. ^Casselman, William Gordon."Castor".Bill Casselman's Canadian Word of the Day.Archived fromthe originalon 2011-02-03.Retrieved2014-08-09.
  7. ^"Seed Oil Prices"(PDF).United States Department of Agriculture.July 2007. p. 31. Archived fromthe original(PDF)on April 6, 2008.Retrieved2008-08-10.
  8. ^abc"Castor oil".Drugs. 3 October 2022.Archivedfrom the original on 20 April 2023.Retrieved20 April2023.
  9. ^Wilson, R; Van Schie, BJ; Howes, D (1998). "Overview of the preparation, use and biological studies on polyglycerol polyricinoleate (PGPR)".Food and Chemical Toxicology.36(9–10): 711–8.doi:10.1016/S0278-6915(98)00057-X.PMID9737417.
  10. ^"Safety datawsheet cremophor El Castor Oil"(PDF).sfm.state.or.us.Archived fromthe original(PDF)on 2017-12-06.Retrieved2016-12-05.
  11. ^Busso, C; Castro-Prado, MA (March 2004)."Cremophor EL stimulates mitotic recombination in uvsH//uvsH diploid strain of Aspergillus nidulans".Anais da Academia Brasileira de Ciências.76(1): 49–55.doi:10.1590/S0001-37652004000100005.PMID15048194.
  12. ^Bryan, Cyril P. (1930).The Papyrus Ebers, Translated from the German Version by Cyril P. Bryan(PDF).London: Geoffrey Bles. p. 44. Archived fromthe original(PDF)on 2013-09-21.
  13. ^Bryan, p. xvii
  14. ^"Castor Oil".American Cancer Society.March 2011. Archived fromthe originalon 2013-02-09.Retrieved2013-09-22.
  15. ^Davis, L (November 1984)."The use of castor oil to stimulate labor in patients with premature rupture of membranes".Journal of Nurse-Midwifery.29(6): 366–370.doi:10.1016/0091-2182(84)90166-6.
  16. ^Kelly, AJ; Kavanagh, J; Thomas, J (2013)."Castor oil, bath and/or enema for cervical priming and induction of labour".Cochrane Database of Systematic Reviews.2013(7): CD003099.doi:10.1002/14651858.CD003099.pub2.PMC7138266.PMID23881775.
  17. ^Garry, D.; Figueroa, R.; Guillaume, J.; Cucco, V. (January 2000)."Use of castor oil in pregnancies at term".Alternative Therapies in Health and Medicine.6(1): 77–79.ISSN1078-6791.PMID10631825.
  18. ^"CASTOR BEAN: Overview, Uses, Side Effects, Precautions, Interactions, Dosing and Reviews".webmd.Retrieved2024-04-25.
  19. ^abAmerizadeh, Atefeh; Farajzadegan, Ziba; Asgary, Sedigheh (2022)."Effect and Safety of Castor Oil on Labor Induction and Prevalence of Vaginal Delivery: A Systematic Review and Meta-Analysis".Iranian Journal of Nursing and Midwifery Research.27(4): 251–259.doi:10.4103/ijnmr.ijnmr_7_21(inactive 2024-05-02).ISSN1735-9066.PMC9580580.PMID36275342.{{cite journal}}:CS1 maint: DOI inactive as of May 2024 (link)
  20. ^For an American example seeDavid J. Rothman (1980).Conscience and Convenience: The Asylum and Its Alternatives in Progressive America.Transaction Publishers. p. 279.ISBN9780202365091.Archivedfrom the original on 2023-01-14.Retrieved2015-10-29.
  21. ^For a Canadian examples seeNeil Sutherland (1997).Growing Up: Childhood in English Canada from the Great War to the Age of Television.University of Toronto Press. p.87.ISBN9780802079831.Retrieved2015-10-29.
  22. ^Journal of the American Medical Association.American Medical Association. 1919. p. 1699.Archivedfrom the original on 2023-01-14.Retrieved2015-10-29.
  23. ^Cecilia Leong-Salobir (2011).Food Culture in Colonial Asia: A Taste of Empire.Taylor & Francis. p. 66.ISBN9781136726545.Archivedfrom the original on 2023-01-14.Retrieved2016-01-08.
  24. ^Adam., Hochschild (1999).King Leopold's ghost: a story of greed, terror, and heroism in Colonial Africa(1st Mariner books ed.). Boston: Houghton Mifflin. p. 166.ISBN978-0547525730.OCLC759834634.
  25. ^abcdPreston, Paul (2012).The Spanish holocaust: inquisition and extermination in twentieth-century Spain.Internet Archive. New York: W.W. Norton & Co. pp. 139, 156, 169, 187, 201, 202, 212, 310, 315, 321, 326, 449.ISBN978-0-393-06476-6.
  26. ^Juan, Carmen Miguel (2016-04-06)."Mujeres y dictadura franquista: la historia silenciada".elDiario.es(in Spanish).Retrieved2023-12-16.
  27. ^Juan, Carmen Miguel (2016-04-06)."Mujeres y dictadura franquista: la historia silenciada".elDiario.es(in Spanish).Retrieved2023-12-16.
  28. ^"Italy The rise of Mussolini".Encyclopædia Britannica Online.Encyclopædia Britannica. 2007. Archived fromthe originalon October 14, 2007.Retrieved2007-08-03.
  29. ^"Benito's Birthday".Time, in partnership with CNN. August 6, 1923. Archived fromthe originalon April 7, 2008.Retrieved2007-08-03.
  30. ^Bosworth, R. J. B. (2002).Mussolini.New York: Arnold/Oxford Univ. Press.ISBN978-0-340-73144-4.
  31. ^"Bearded like a medieval condottiere, bluff yet suave, fearless and supple, [Italo Balbo] was not the type to pass unnoticed anywhere. His admirers here chose to forget the Blackshirt club-wielder and reputed inventor of the castor-oil treatment for Fascist foes"
    Marshal BalboArchived2021-04-29 at theWayback Machine,The New York Times,July 1, 1940, p. 18.
  32. ^Cecil Adams (1994-04-22)."Did Mussolini use castor oil as an instrument of torture?".The Straight Dope.Archivedfrom the original on 2020-11-01.Retrieved2014-08-09.
  33. ^Williams, Cheryll (1 July 2012).Medicinal Plants in Australia Volume 3: Plants, Potions and Poisons.Rosenberg Publishing. p. 309.ISBN978-1-925078-07-7.Archivedfrom the original on 20 April 2023.Retrieved8 March2023.
  34. ^Nathan, Alan (2010).Non-prescription Medicines.Pharmaceutical Press. p. 206.ISBN978-0-85369-886-9.Archivedfrom the original on 20 April 2023.Retrieved8 March2023.
  35. ^Howarth, GA (June 2003). "Polyurethanes, polyurethane dispersions and polyureas: Past, present and future".Surface Coatings International Part B: Coatings Transactions.86(2): 111–118.doi:10.1007/bf02699621.ISSN1476-4865.S2CID93574741.
  36. ^Ogunniyi, D. S. (2006-06-01)."Castor oil: A vital industrial raw material".Bioresource Technology.97(9): 1086–1091.Bibcode:2006BiTec..97.1086O.doi:10.1016/j.biortech.2005.03.028.ISSN0960-8524.PMID15919203.Archivedfrom the original on 2016-11-30.Retrieved2023-03-09.
  37. ^Ma, Yufeng; Wang, Rui; Li, Qiaoguang; Li, Mei; Liu, Chengguo; Jia, Puyou (2021-03-24)."Castor oil as a platform for preparing bio-based chemicals and polymer materials".Green Materials.10(3): 99–109.doi:10.1680/jgrma.20.00085.ISSN2049-1220.S2CID233687152.Archivedfrom the original on 2023-01-31.Retrieved2022-04-18.
  38. ^"Multiple uses of castor oil".Archived fromthe originalon 2007-09-29.Retrieved2007-08-02.
  39. ^Mutlu, Hatice; Meier, Michael A. R. (2010-01-25). "Castor oil as a renewable resource for the chemical industry".European Journal of Lipid Science and Technology.112:10–30.doi:10.1002/ejlt.200900138.
  40. ^Ogunniyi, D.S. (June 2006). "Castor oil: A vital industrial raw material".Bioresource Technology.97(9): 1086–91.Bibcode:2006BiTec..97.1086O.doi:10.1016/j.biortech.2005.03.028.PMID15919203.
  41. ^Ashford's Dictionary of Industrial Chemicals, Third edition, 2011, page 6162
  42. ^Hermansen, Ralph D. (2017-03-16).Polymeric Thermosetting Compounds: Innovative Aspects of Their Formulation Technology.CRC Press.ISBN9781771883153.Archivedfrom the original on 2023-01-14.Retrieved2020-11-09.
  43. ^Ash, Michael; Ash, Irene (2007).Handbook of fillers, extenders, and diluents(2nd ed.). Endicott, NY: Synapse Information Resources. p. 82.ISBN9781890595968.
  44. ^Kirk-Othmer Encyclopedia of Chemical Technology.Archived fromthe originalon July 14, 2011.Retrieved2010-07-12.
  45. ^"Chemical modification to improve vegetable oil lubricants".Archivedfrom the original on 2006-10-01.Retrieved2007-08-02.
  46. ^"Petroleum Oil and the Environment".DOE.Archivedfrom the original on 2009-08-23.Retrieved2006-12-28.
  47. ^McGuire, Nancy (2004)."Taming the Bean".The American Chemical Society. Archived fromthe originalon September 27, 2006.Retrieved2007-08-02.
  48. ^Brady, George S.; Clauser, Henry R.; Vaccari, John (1997).Materials Handbook(14th ed.). New York: McGraw-Hill.ISBN978-0070070844.
  49. ^Older, Jules (2000).Backroad and Offroad Biking.Mechanicsburg, PA: Stackpole Books. p. 37.ISBN978-0811731508.
  50. ^Guilmartin, John F. Jr. (1994). "Technology and Strategy: What Are the Limits?".Two Historians in Technology and War.United States Army War College, Strategic Studies Institute. p. 10.ISBN978-1428915220.
  51. ^Fisher, Suzanne Hayes (1999). "Aircraft, production during the war". In Tucker, Spencer C.; Wood, Laura Matysek; Murphy, Justin D. (eds.).The European Powers in the First World War: An Encyclopedia.Taylor & Francis. p. 10.ISBN978-0815333517.
  52. ^U.S. Tariff Commission(1921).Tariff Information Surveys on the Articles in Paragraphs 44 and 45 of the Tariff Act of 1913.Washington, D.C.: Government Printing Office. p. 40.
  53. ^abPenda, H (2017).Herbal Soaps & Detergents Handbook.Delhi, India: NIIR. p. 121.ISBN9789381039007.
  54. ^Biodiesel from Castor Oil: A Promising Fuel for Cold Weather(PDF)ArchivedJune 16, 2013, at theWayback Machineby Carmen Leonor Barajas Forero, 2004-10-12. Retrieved 2012-01-24.
  55. ^The Promise of the Castor BeanArchivedMarch 9, 2016, at theWayback Machineby Elizabeth Johnson, Biodiesel Magazine, 2004-12-01. Retrieved 2012-01-24.
  56. ^Auld, DL; Pinkerton, SD; Rolfe, R; Ghetie, V; et al. (March–April 1999)."Selection of castor for divergent concentrations of ricin and ricinus communis agglutinin".Crop Science.39(2): 353–7.doi:10.2135/cropsci1999.0011183X003900020008x.Archived fromthe originalon 2008-10-12.Retrieved2007-07-31.
  57. ^Dierig, David A. (1995)."Lesquerella".New Crop FactSHEET.Center for New Crops & Plant Products, at Purdue University.Archivedfrom the original on 2007-10-25.Retrieved2007-08-01.

Further reading[edit]

External links[edit]

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