Furfural 490020 220711894 2008-06-21T05:24:44Z DOI bot 6652755 Citation maintenance. Initiated by [[User:Fconaway|Fconaway]]. You can [[WP:DOI|use this bot]] yourself! Please [[User:DOI_bot/bugs|report any bugs]]. {{chembox new | ImageFileL1 = Furfural structure.png | ImageSizeL1 = 120px | ImageFileR1 = Furfural-3D-vdW.png | ImageSizeR1 = 120px | IUPACName = Furan-2-carbaldehyde | OtherNames = furfural, furan-2-carboxaldehyde, fural, furfuraldehyde, pyromucic aldehyde | Section1 = {{Chembox Identifiers | Abbreviations = | CASNo = 98-01-1 | EINECS = | PubChem = 7362 | SMILES = O=Cc1ccco1 | InChI = 1/C5H4O2/c6-4-5-2-1-3-7-5/h1-4H | RTECS = | MeSHName = | ChEBI = | KEGG = | ATCCode = }} | Section2 = {{Chembox Properties | C = 5 | H = 4 | O = 2 | Formula = C<sub>5</sub>H<sub>4</sub>O<sub>2</sub> | MolarMass = 96.09 g/mol | Appearance = Colorless oil | Density = 1.16 g/mL liquid | MeltingPt = -36.5 °C | Melting_notes = | BoilingPt = 161.7 °C | Boiling_notes = | Solubility = | SolubleOther = | Solvent = | pKa = | pKb = | IsoelectricPt = | SpecRotation = | RefractIndex = | Viscosity = | Dipole = }} | Section3 = {{Chembox Structure | CrystalStruct = | Coordination = | MolShape = | Dipole = }} | Section4 = {{Chembox Thermochemistry | DeltaHf = | DeltaHc = | Entropy = | HeatCapacity = }} | Section5 = {{Chembox Pharmacology | AdminRoutes = | Bioavail = | Metabolism = | HalfLife = | ProteinBound | Excretion = | Legal_status = | Legal_US = | Legal_UK = | Legal_AU = | Legal_CA = | PregCat = | PregCat_AU = | PregCat_US = }} | Section6 = {{Chembox Explosive | ShockSens = | FrictionSens = | ExplosiveV = | REFactor = }} | Section7 = {{Chembox Hazards | ExternalMSDS = | EUClass = | EUIndex = | MainHazards = | NFPA-H = | NFPA-F = | NFPA-R = | NFPA-O = | RPhrases = | SPhrases = | RSPhrases = | FlashPt = 62 °C | Autoignition = | ExploLimits = | PEL = }} | Section8 = {{Chembox Related | OtherAnions = | OtherCations = | OtherFunctn = | Function = | OtherCpds = }} }} The [[chemical compound]] '''furfural''' is an industrial chemical derived from a variety of [[agriculture|agricultural]] byproducts, including [[maize|corncobs]], [[oat]] and [[wheat]] [[bran]], and [[sawdust]]. The name ''furfural'' comes from the [[Latin]] word ''furfur'', meaning bran, referring to its usual source. Furfural is an [[aromatic]] [[aldehyde]], with the ring structure shown at right. Its [[chemical formula]] is [[carbon|C]]<sub>5</sub> [[hydrogen|H]]<sub>4</sub> [[oxygen|O]]<sub>2</sub>. In its pure state, it is a colorless oily liquid with the odor of [[almond]]s, but upon exposure to air it quickly becomes yellow. ==History== Furfural was first isolated in 1832 by the [[Germany|German]] [[chemist]] [[Johann Wolfgang Döbereiner]], who formed a very small quantity of it as a byproduct of [[formic acid]] synthesis.<ref> {{cite journal | title = Ueber die medicinische und chemische Anwendung und die vortheilhafte Darstellung der Ameisensäure | pages = 141–146 | author = J. W. Döbereiner | volume = 3 | issue = 2 | year = 1832 | journal = Berichte der deutschen chemischen Gesellschaft | doi = 10.1002/jlac.18320030206}}</ref> At the time, formic acid was formed by the [[distillation]] of dead [[ant]]s, and Döbereiner's ant bodies probably contained some plant matter. In 1840, the [[Scotland|Scottish]] chemist [[John Stenhouse]] found that the same chemical could be produced by distilling a wide variety of crop materials, including corn, oats, bran, and sawdust, with aqueous [[sulfuric acid]], and he determined that this chemical had an [[empirical formula]] of C<sub>5</sub>H<sub>4</sub>O<sub>2</sub>. In 1901, the German chemist [[Carl Harries]] deduced furfural's structure. Except for occasional use in [[perfume]], furfural remained a relatively obscure chemical until 1922, when the [[Quaker Oats Company]] began mass-producing it from oat hulls. Today, furfural is still produced from agricultural byproducts like [[bagasse|sugarcane bagasse]] and [[corn]] cobs. ==Properties== Furfural's physical properties are summarized in the table at right. Furfural dissolves readily in most polar [[organic chemistry|organic]] solvents, but is only slightly soluble in either [[water]] or [[alkane]]s. Chemically, furfural participates in the same kinds of reactions as other aldehydes and other aromatic compounds. The aromatic stability of furfural is not as great as in [[benzene]], and furfural participates in [[hydrogenation]] and other [[addition reaction]]s more readily than many other aromatics. When heated above 250 °C, furfural decomposes into [[furan]] and [[carbon monoxide]], sometimes explosively. When heated in the presence of acids, furfural irreversibly solidifies into a hard thermosetting [[resin]]. ==Production== Many plant materials contain the [[polysaccharide]] [[hemicellulose]], a [[polymer]] of [[sugar]]s containing five carbon atoms each. When heated with sulfuric acid, hemicellulose undergoes [[hydrolysis]] to yield these sugars, principally [[xylose]]. Under the same conditions of heat and acid, xylose and other five carbon sugars undergo dehydration, losing three water molecules to become furfural: :[[xylose|C<sub>5</sub>H<sub>10</sub>O<sub>5</sub>]] → C<sub>5</sub>H<sub>4</sub>O<sub>2</sub> + 3 [[water|H<sub>2</sub>O]] For crop residue feedstocks, about 10% of the mass of the original plant matter can be recovered as furfural. Furfural and water evaporate together from the reaction mixture, and separate upon condensation. Global total capacity of production is about 450,000 ton. [[China]] is the biggest supplier of this product and they have about a half of global capacity. In the laboratory, synthesis of furfural from corn cobs takes place by [[reflux]] with dilute [[sulfuric acid]] <ref>{{OrgSynth | title = Furfural | volume = 1 | pages = 49 | year = 1921 | collvol = 1 | collvolpages = 280 | author = Roger Adams and V. Voorhees | prep = cv1p0280}}</ref>. ==Uses== Furfural is used as a [[solvent]] in [[petrochemical]] [[refining]] to extract [[diene]]s (which are used to make synthetic [[rubber]]) from other [[hydrocarbon]]s. Furfural, as well as its derivative [[furfuryl alcohol]], can be used either by themselves or in together with [[phenol]], [[acetone]], or [[urea]] to make solid resins. Such resins are used in making [[fiberglass]], some [[aircraft]] components, and automotive [[brake]]s. Furfural is also used as a chemical intermediate in the production of the solvents [[furan]] and [[tetrahydrofuran]]. [[Hydroxymethylfurfural]] has been identified in a wide variety of heat processed foods. ==Safety== When ingested or inhaled, furfural can cause [[intoxication]], including [[Euphoria (emotion)|euphoria]], [[headache]], [[dizziness]], [[nausea]], and eventual unconsciousness and death due to respiratory failure. Contact with furfural irritates the [[skin]] and [[respiratory tract]] and can cause the [[lung]]s to fill with fluid. Chronic skin exposure can lead to a skin [[allergy]] to the substance, as well as an unusual susceptibility to [[sunburn]]. In toxicity studies, furfural has led to [[tumor]]s, [[mutation]]s, and [[liver]] and [[kidney]] damage in animals. ==References== <references/> [[Category:flavors]] [[Category:Furans]] [[Category:Aldehydes]] [[Category:Solvents]] [[ar:فرفورال]] [[de:Furfural]] [[es:Furfural]] [[fr:Furfural]] [[it:Furfurale]] [[lv:Furfurols]] [[nl:Furfural]] [[ja:フルフラール]] [[pl:Furfural]] [[pt:Furfural]] [[ru:Фурфурол]] [[fi:Furfuraali]] [[sv:Furfural]] [[zh:糠醛]]