Paraffin
wax
Paraffin wax
Paraffin wax is a white or colourless soft solid deriv-able from petroleum,coal or oil shale,that consists of a mixture of hydrocarbon molecules containing between twenty and forty carbon atoms.It is solid at room tem-perature and begins to melt above approximately37°C (99°F);[1]its boiling point is>370°C(698°F).[2]Com-mon applications for paraffin wax include lubrication, electrical insulation,and candles;[3]dyed paraffin wax can be made into crayons.It is distinct from kerosene,an-other petroleum product that is sometimes called paraf-fin.
Paraffin candles are odorless,and bluish-white in color. Paraffin wax wasfirst created in the1850s,and marked a major advancement in candlemaking technology,as it burned more cleanly and reliably than tallow candles,and was cheaper to produce.[4]
In chemistry,paraffin is used synonymously with alkane,indicating hydrocarbons with the general for-mula C n H₂n₊₂.The name is derived from Latin parum (“barely”)+affinis,meaning“lacking affinity"or“lacking reactivity",referring to paraffin’s unreactive nature.[5]
1Properties
Paraffin wax is mostly found as a white,odorless,taste-less,waxy solid,with a typical melting point between about46and68°C(115and154°F),[6]and a density of around900kg/m3.[7]It is insoluble in water,but sol-uble in ether,benzene,and certain esters.Paraffin is un-affected by most common chemical reagents but burns readily.[8]Its heat of combustion is42
kJ/g.
The hydrocarbon C31H64is a typical component of paraffin wax. Paraffin wax is an excellent electrical insulator,with a resistivity of between1013and1017ohm metre.[9]This is better than nearly all other materials except some plastics (notably Teflon).It is an effective neutron moderator and was used in James Chadwick's1932experiments to iden-tify the neutron.[10][11]
Paraffin wax is an excellent material for storing heat,with a specific heat capacity of2.14–2.9J g−1K−1(joules per gram kelvin)and a heat of fusion of200–220J g−1.[12]This property is exploited in modified drywall for home building material:a certain type of wax(with the right melting point)is infused in the drywall dur-ing manufacture so that it melts during the day,ab-sorbing heat,and solidifie
s again at night,releasing the heat.[13]Paraffin wax phase-change cooling coupled with retractable radiators was used to cool the electronics of the Lunar Rover.[14]Wax expands considerably when it melts and this allows its use in wax thermostatic element thermostats for industrial,domestic and,particularly,au-tomobile purposes.[15][16]
2History
Paraffin wax wasfirst created in the1850s when chemists first developed the means to efficiently separate and re-fine the waxy substances naturally occurring in petroleum. Paraffin represented a major advance in the candlemak-ing industry because it burned more cleanly and reliably, and was cheaper to manufacture than any other candle fuel.Paraffin wax initially suffered from having a low melting point,however,a shortcoming later remedied by the addition of harder stearic acid.The production of paraffin wax enjoyed a boom in the early20th cen-tury as a result of the growth of the meatpacking and oil industries,which created paraffin and stearic acid as byproducts.[17]
3Manufacturing
The feedstock for paraffin is slack wax,which is a mix-ture of oil and wax,a byproduct from the refining of lu-bricating oil.
1
24APPLICATIONS
Thefirst step in making paraffin wax is to remove the oil(de-oiling or de-waxing)from the slack wax.The oil is separated through crystallization.Most commonly,the slack wax is heated,mixed with one or more solvents such as a ketone and then cooled.As it cools wax crystallizes out of the solution,leaving only oil in the solution.This mixture isfiltered into two streams:solid(wax plus some solvent)and liquid(oil and solvent).After the solvent is recovered by distillation,the resulting products are called “product wax”(or“press wax”)and“foots oil”.The lower the percentage of oil in the wax the more refined it is con-sidered(semi-refined versus fully refined).[18]The prod-uct wax may be further processed to remove colors and odors.The wax mayfinally be blended together to give certain desired properties such as melt point and pen-etration.Paraffin wax is sold in either liquid or solid form.[19][20][21]
4Applications
In industrial applications,it is often useful to modify the crystal properties of the paraffin wax,typically by adding branching to the existing carbon backbone chain. The modification is usually done with ad
ditives,such as EVA copolymers,microcrystalline wax,or forms of polyethylene.The branched properties result in a mod-ified paraffin with a higher viscosity,smaller crystalline structure,and modified functional properties.Pure paraf-fin wax is rarely used for carving original models for casting metal and other materials in the lost wax pro-cess,as it is relatively brittle at room temperature and presents the risks of chipping and breakage when worked. Soft and pliable waxes,like beeswax,may be preferred for such sculpture,but"investment casting waxes,”often paraffin-based,are expressly formulated for the purpose. In a pathology laboratory,paraffin wax is used to impreg-nate tissue prior to sectioning thin samples of tissue.Wa-ter is removed from tissue through ascending strengths of alcohol(75%to absolute)and the tissue is cleared in an organic solvent such as xylene.The tissue is then placed in paraffin wax for a number of hours and then set in a mold with wax to cool and solidify;sections are cut then on a microtome.
4.1Other uses
•Candle-making
•Coatings for waxed paper or cloth
•Food-grade paraffin wax:
•Shiny coating used in candy-making;al-
though edible,it is nondigestible,passing right
through the body without being broken down
•Coating for many kinds of hard cheese,like
Edam cheese
•Sealant for jars,cans,and bottles
•Chewing gum additive
•Investment casting
•Anti-caking agent,moisture repellent,and dustbind-ing coatings for fertilizers
•Agent for preparation of specimens for histology •Bullet lubricant–with other ingredients,such as olive oil and beeswax
•Phlegmatizing agent,commonly used to sta-bilise/desensitize high explosives such as RDX •Crayons
•Solid propellant for hybrid rocket motors[22]•Component of surfwax,used for grip on surfboards in surfing
•Component of glide wax,used on skis and snowboards
•Friction-reducer,for use on handrails and cement ledges,commonly used in skateboarding •Ink.Used as the basis for solid ink different color blocks of wax for thermal printers.The wax is melted and then sprayed on the paper producing im-ages with a shiny surface
•Microwax:[23]food additive,a glazing agent with E number E905
•Forensic investigations:the nitrate test uses paraffin wax to detect nitrates and nitrites on the hand of a shooting suspect
•Antiozonant agents:blends of paraffin and mi-cro waxes are used in rubber compounds to pre-vent cracking of the rubber;the admixture of wax migrates to the surface of the product and forms a protective layer.The layer can also act as a release agent,helping the product separate from its moul
d.[24]
•Mechanical thermostats and actuators,as an expan-sion medium for activating such devices[16]•“Potting”guitar pickups,which reduces micro-phonic feedback caused from the subtle movements of the pole pieces
•“Potting”of local oscillator coils to prevent micro-phonic frequency modulation in low end FM radios.•Texitle manufacturing processes,such as that used for Eisengarn thread.
•Wax baths for beauty and therapy purposes •Thickening agent in many paintballs
3
•Moisturiser in toiletries and cosmetics such as Vaseline,though potentially comedogenic.
•Prevents oxidation on the surface of polished steel and iron[25]
•Phase change material for thermal energy storage •MESSENGER(Mercury spacecraft)When
the spacecraft was unable to radiate excessive
heat.[26]
•Manufacture of boiled leather armor and books •Skateboard wax
•Paraffin microactuator[27]
•Neutron radiation shielding
•waterproofing agent for waxed cotton garments and commercially important in the early water proofing of ship sails.
5Occupational safety
People can be exposed to paraffin in the workplace by breathing it in,skin contact,and eye contact.The National Institute for Occupational Safety and Health (NIOSH)has set a recommended exposure limit(REL) for paraffin wax fume exposure of2mg/m3over an8-hour workday.[28]
6See also
•Oligomer
•Ozokerite
7References
[1]Freund,Mihály;Mózes,Gyula(1982).Paraffin products:
properties,technologies,applications.Translated by Jakab,
E.Amsterdam,Netherlands:Elsevier.p.121.ISBN0-
444-99712-1.
[2]“Paraffin Wax”.Chemical book.Retrieved25October
2013.
[3]Raw materials and candles production processes,AECM
[4]“History of Candles”.National Candle Association.Re-
trieved25February2016.
[5]“Paraffin,n”.Oxford English Dictionary.Oxford,Eng-
land:Oxford University Press.March2009.
[6]Nasser,William E(1999).“Waxes,Natural and Syn-
thetic”.In McKetta,John J.Encyclopedia of Chemical Processing and Design.67.New York:Marcel Dekker.
p.17.ISBN0-8247-2618-9.This can vary widely,even outside the quoted range,according to such factors as oil content and crystalline structure.
[7]Kaye,George William Clarkson;Laby,Thomas Howell.
“Mechanical properties of materials”.Kaye and Laby Ta-bles of Physical and Chemical Constants.National Physi-cal Laboratory.Retrieved25October2013.
[8]Seager,Spencer L.;Slabaugh,Michael.“Alkane reac-
tions”.Chemistry for Today:General,Organic,and Bio-chemistry.Belmont,CA:Cengage.p.364.ISBN978-0-538-73332-8.
[9]“Electrical insulating materials”.Kaye and Laby Tables of
Physical and Chemical Constants.National Physical Lab-oratory.1995.Retrieved25October2013.
[10]“Attenuation of fast neutrons:neutron moderation and
diffusion”.Kaye and Laby Tables of Physical and Chem-ical Constants.National Physical Laboratory.Retrieved 25October2013.
[11]Rhodes,Richard(1981).The Making of the Atomic Bomb.
New York:Simon and Schuster.p.163.ISBN0-671-44133-7.
[12]“Specific Heat Capacity”.uk Science and
Engineering Encyclopedia.Dirac Delta Consultants Ltd, Warwick,England.Retrieved25October2013.
[13]“Micronal PCM SmartBoard”.
[14]Dean,W.G.;Karu,Z.S.(February1993).“Space Station
thermal storage/refrigeration system research and devel-opment”.Final Report Lockheed Missiles and Space Co.
NASA.pt.....D.
[15]Wax-pellet thermostat United States Patent4948043
[16]Bodén,Roger.“Paraffin Microactuator”(pdf).Materi-
als Science Sensors and Actuators.University of Uppsala.
Retrieved25October2013.
[17]“History of Candles”.National Candle Association.Re-
trieved25February2016.
[18]“Paraffin Wax(Fully Refined)".Barasat Wax Refiner.Re-
trieved21December2012.
[19]“Wax Refining”.The International Group,Inc.Retrieved
21December2012.
[20]“Paraffin wax”.Bitumen Engineering.Retrieved21De-
cember2012.
[21]“Manufacturing Process”.Barasat Wax Refiner.Re-
trieved21December2012.
[22]Staff(Fall2004).“Rocket motor uses common household
product for fuel”(PDF).OASIS Ocean Air Space Industry Site.Stennis Space Center Pearlington,MS:NASA.1(3):
6.Retrieved28November2008.
[23]igiwax/igi-products/by-type/
microcrystallinewax.html
47REFERENCES
retractable
[24](Freund&Mózes1982,p.272)
[25]Dick,William B(1872).“Encyclopedia Of Practical Re-
ceipts And Processes”.New York:Dick and Fitzgerald.
Retrieved25October2013.
[26]“Instrument Information”.NASA.2007.Retrieved24
January2017.
[27]Ogden,Sam;Klintberg,Lena;Thornell,Greger;
Hjort,Klas;Bodén,Roger(30November2013).
“Review on miniaturized paraffin phase change actua-
tors,valves,and pumps”.Microfluidics and Nanofluidics.
doi:10.1007/s10404-013-1289-3.
[28]“CDC-NIOSH Pocket Guide to Chemical Hazards-
Paraffin wax fume”.v.Retrieved2015-11-
27.
5 8Text and image sources,contributors,and licenses
8.1Text
•Paraffin wax Source:/wiki/Paraffin_wax?oldid=764359523Contributors:AxelBoldt,Bryan Derksen,The Anome,Setok,Heron,Edward,Michael Hardy,Liftarn,Error,Andres,Schneelocke,Jay,Michaeln,Furrykef,Snicker,Unfree,Graeme Bartlett,Lunkwill,Wighson,Bensaccount,Unconcerned,Finn-Zoltan,Macrakis,Foobar,Alvestrand,Utcursch,Oknazevad,Jcw69,Fg2, Picapica,Discospinster,Rich Farmbrough,Cacycle,Cfailde,Rgdboer,Dennis Brown,Bobo192,Alphax,Haham hanuka,Andrewpmk, Linmhall,Hadlock,Wtshymanski,Alai,BlueCanoe,Woohookitty,Bunthorne,EmmanuelM,Mandarax,Rnt20,Graham87,KevinHarbin, Sjö,Angusmclellan,Pjetter,SMC,Durin,Fish and karate,Vuong Ngan Ha,Lzz,Old Moonraker,Margosbot~enwiki,Nihiltres,Srlef-fler,Chobot,Jlittlet,Jcabraham,Gaius Cornelius,Shaddack,Salsb,Stassats,Kylelynch,Diotti,David Underdown,TheMadBaron,Btrujill,
A Doon,Vanka5,SmackBot,Eskimbot,Brossow,Kintetsubuffalo,Edgar181,Chris the speller,Persian Poet Gal,SchfiftyThree,WD-
Graham,Jennica,OSborn,Jmlk17,T-borg,Smokefoot,Drphilharmonic,JohnnyBatina,Bige1977,Lambiam,John,JackLumber,Bjso, Diverman,Peterlewis,Beetstra,Martinp23,Kvng,Wizard191,Kevin R Johnson,Tawkerbot2,Mikiemike,CmdrObot,Threehead,Mean-meancoffeebean,N2e,Smoove Z,Oosoom,Rifleman82,Pdxuser,ErrantX,Doughpat,Thijs!bot,Barticus88,Cocoma,John254,Greg L,Nick Number,Opelio,JAnDbot,Bongwarrior,VoABot II,Mrund,Usien6,28421u2232nfenfcenc,Beagel,Enaidmawr,MartinBot, Jpyeron,J.delanoy,The dark lord trombonator,SlightlyMad,VolkovBot,Nailhead76,TXiKiBoT,Oshwah,Rei-bot,Clarince63,Broad-bot,BotKung,Meters,M1a1mstrgn,System.out.print("!"),Kbrose,Biscuittin,SieBot,Android Mouse,Pigeon1231,Explicit,ClueBot, Ithunn,Wysprgr2005,08riodgj1,Farras Octara,Puppy8800,Boneyard90,Roadcrusher3,Ark25,ChrisHodgesUK,Zappa711,Aitias, Plasmic Physics,Ptolom,Wnt,Ginbot86,Gmhofmann,Doronpapo,Addbot,Sebcloug,CanadianLinuxUser,HuyZ,SamatBot,Alpin-wolf,OlEnglish,ScAvenger,David0811,KitemanSA,LuK3,Salars412,Luckas-bot,Amirobot,Anypodetos,Synchronism,AnomieBOT, Kristen Eriksen,Götz,Jim1138,Mdmuzammil001,
Mahmudmasri,Materialscientist,Citation bot,Bob Burkhardt,ArthurBot,Que-bec99,Transity,GrouchoBot,Middle8,Jack B108,BoomerAB,Prari,FrescoBot,D'ohBot,Citation bot1,Jauhienij,Trappist the monk, Fastilysock,Suffusion of Yellow,Jfmantis,Jared105,Beyond My Ken,GrindtXX,Erianna,IGeMiNix,Scientific29,MacStep,Clue-Bot NG,MelbourneStar,Rezabot,Dr mems,Helpful Pixie Bot,BG19bot,Zkrywyj,CitationCleanerBot,Lekro,ChrisGualtieri,Kbog, Awsfam9,Sebastienroblin,Tentinator,Bulingon,DavidLeighEllis,Jakub sza,Noyster,Schmidtph,Monkbot,AwesoMan3000,Ackarp, Emily Temple-Wood(NIOSH),KasparBot,Oluwa2Chainz,Labtek00,Felixkrater and Anonymous:273
8.2Images
•File:Hentriacontane.svg Source:/wikipedia/commons/1/17/Hentriacontane.svg License:Public domain Contributors:Own work Original artist:Edgar181
•File:Paraffin.jpg Source:/wikipedia/commons/d/d7/Paraffin.jpg License:CC BY-SA3.0Contributors: Own work Original artist:Gmhofmann
8.3Content license
•Creative Commons Attribution-Share Alike3.0

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