- Adipic acid
Chembox new
Name = Adipic acid
ImageFile = Adipic_acid_structure.png
ImageName = Adipic acid
ImageFile1 = Adipic acid-3d.png
IUPACName = hexanedioic acid
OtherNames = butane-1,4-dicarboxylic acid
Section1 = Chembox Identifiers
SMILES = OC(=O)CCCCC(=O)O
CASNo = 124-04-9
ChemSpiderID = 191
RTECS =
Section2 = Chembox Properties
C=6|H=10|O=4
Appearance = White crystals
Density = 1.36 g/cm³
Solubility = slightly soluble
MeltingPt = 152 °C (425 K)
BoilingPt = 337 °C (610 K)
pKa = 4.43, 5.41
Section3 = Chembox Structure
Coordination =
CrystalStruct =
Dipole =
Section7 = Chembox Hazards
MainHazards = flammable
FlashPt = 232 °C
RPhrases = R: R36
Section8 = Chembox Related
Function =dicarboxylic acid s
OtherFunctn =glutaric acid pimelic acid
OtherCpds =hexanoic acid Adipic acid (
IUPAC systematic name : hexanedioic acid) is a dicarboxylic acid . It is a white crystalline powder. Due to its long aliphatic chain, it is not very soluble in water.Preparation
Historically, adipic acid was prepared from various fats using oxidation. Current commercial adipic acid is produced from
cyclohexane by two oxidation steps.# Cyclohexane + O2 →
cyclohexanol andcyclohexanone +byproducts
# cyclohexanol/cyclohexanone +nitric acid + air → adipic acid + nitrous oxide(The mixture of cyclohexanol and cyclohexanone produced from cyclohexane is commercially called "KA oil", the abbreviation of "Ketone-Alcohol oil".)
Other patented processes include those using
phenol as feedstock. For example, phenol can be oxidized to KA oil, which is further processed give adipic acid. [US patent|7,250,537] Utilizing principles ofgreen chemistry , a new method of synthesis has been developed, which involves oxidizing cyclohexene withhydrogen peroxide via atungsten catalyst and aphase transfer catalyst to produce adipic acid. [cite journal |author=Sato, K.; Aoki, M.; Noyori, R. |title=A "Green" route to adipic acid: direct oxidation of cyclohexenes with 30 percent hydrogen peroxide |journal=Science |volume=281 |issue=5383 |pages=1646–7 |year=1998|doi = 10.1126/science. |doi_brokendate=2008-06-22] The waste product is water.Uses
By far the main use of adipic acid is as monomer for the production of
nylon by apolycondensation reaction withhexamethylene diamine forming 6,6-nylon . Other uses include:* Monomer for production of
Polyurethane * reactant to form plasticizers and lubricant components
* Food Ingredient as a flavorant and gelling aid.
E-number E355.* FDA citations - GRAS (21 CFR 184.1009), Indirect additive (21 CFR 175.300, 21 CFR 175.320, 21 CFR 176.170, 21 CFR 176.180, 21 CFR 177.1200, 21 CFR 177.1390 , 21 CFR 177.1500, 21 CFR 177.1630 , 21 CFR 177.1680, 21 CFR 177.2420, 21 CFR 177.2600)
* European Union Citations - Decision 1999/217/EC - Flavoing Substance; Directive 95/2/EC, Annex IV - Permitted Food Additive; 2002/72/EC, Annex A - Authorized monomer for Food Contact Plastics
References
External links
* [http://www.chemicalland21.com/arokorhi/industrialchem/organic/ADIPIC%20ACID.htm adipic acid on chemicalland]
* [http://www.solutia.com/pages/corporate/products/product.asp?product=164 Solutia Inc product website]
* [http://ptcl.chem.ox.ac.uk/MSDS/AD/adipic_acid.html Safety data from Oxford University]
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