Cumene

Not to be confused with cumin or cumulene.
Cumene
Skeletal formula of cumene
Ball-and-stick model of the cumene molecule
Names
IUPAC name
(1-methylethyl)benzene
Systematic IUPAC name
prop-2-ylbenzene
2-phenylpropane
Other names
i-propylbenzene
isopropylbenzene
cumol
Identifiers
98-82-8 YesY
ChEBI CHEBI:34656 YesY
ChemSpider 7128 YesY
Jmol interactive 3D Image
KEGG C14396 YesY
PubChem 7406
RTECS number GR8575000
UNII 8Q54S3XE7K YesY
Properties
C9H12
Molar mass 120.20 g·mol−1
Appearance colorless liquid
Odor sharp, gasoline-like
Density 0.862 g cm−3, liquid
Melting point −96 °C (−141 °F; 177 K)
Boiling point 152 °C (306 °F; 425 K)
negligible
Solubility soluble in acetone, ether, ethanol
Vapor pressure 8 mm (20°C)[1]
1.4915 (20 °C)
Viscosity 0.777 cP (21 °C)
Hazards
Main hazards flammable
R-phrases R10,R37,R51/53,R65
S-phrases S24,S37,S61,S62
NFPA 704
Flammability code 3: Liquids and solids that can be ignited under almost all ambient temperature conditions. Flash point between 23 and 38 °C (73 and 100 °F). E.g., gasoline) Health code 2: Intense or continued but not chronic exposure could cause temporary incapacitation or possible residual injury. E.g., chloroform Reactivity code 1: Normally stable, but can become unstable at elevated temperatures and pressures. E.g., calcium Special hazards (white): no codeNFPA 704 four-colored diamond
3
2
1
Flash point 43 °C (109 °F; 316 K)
424 °C (795 °F; 697 K)
Explosive limits 0.9-6.5%
Lethal dose or concentration (LD, LC):
12750 mg/kg (oral, mouse)
1400 mg/kg (oral, rat)[2]
200 ppm (mouse, 7 hr)[2]
8000 ppm (rat, 4 hr)[2]
US health exposure limits (NIOSH):
TWA 50 ppm (245 mg/m3) [skin][1]
TWA 50 ppm (245 mg/m3) [skin][1]
900 ppm[1]
Related compounds
Related compounds
 ethylbenzene
toluene
benzene
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Infobox references

Cumene is the common name for isopropylbenzene, an organic compound that is based on an aromatic hydrocarbon with an aliphatic substitution. It is a constituent of crude oil and refined fuels. It is a flammable colorless liquid that has a boiling point of 152 °C. Nearly all the cumene that is produced as a pure compound on an industrial scale is converted to cumene hydroperoxide, which is an intermediate in the synthesis of other industrially important chemicals, primarily phenol and acetone.

Production

Commercial production of cumene is by Friedel–Crafts alkylation of benzene with propylene. Cumene producers account for approximately 20% of the global demand for benzene.[3] Previously, solid phosphoric acid (SPA) supported on alumina was used as the catalyst. Since the mid-1990s, commercial production has switched to zeolite-based catalysts.[4]

Isopropylbenzene is stable, but may form peroxides in storage if in contact with the air. It is important to test for the presence of peroxides before heating or distilling. The chemical is also flammable and incompatible with strong oxidizing agents. Environmental laboratories commonly test isopropylbenzene using a Gas chromatography–mass spectrometry (GCMS) instrument.[5]

Health effects

A review by the US Department of Health and Human Services found that mice exposed to cumene fumes developed tumors in their lungs and livers. Cumene was anticipated to also be a human carcinogen and was added to the governmental organization's list of carcinogens in 2014.[6]

See also

References

  1. 1 2 3 4 "NIOSH Pocket Guide to Chemical Hazards #0159". National Institute for Occupational Safety and Health (NIOSH).
  2. 1 2 3 "Cumene". Immediately Dangerous to Life and Health. National Institute for Occupational Safety and Health (NIOSH).
  3. ↑ Market Study Benzene, published by Ceresana, July 2011
  4. ↑ The Innovation Group website, page accessed 15/11/07
  5. ↑ http://www.caslab.com/Isopropylbenzene.php5
  6. ↑ Gannon, Megan (October 3, 2014). "4 New Substances Added To List Of Carcinogens". Huffington Post. LiveScience.

External links

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