Cumene
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Names | |||
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Preferred IUPAC name
(1-methylethyl)benzene | |||
Other names | |||
Identifiers | |||
3D model (JSmol) |
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ChEBI | |||
ChemSpider | |||
ECHA InfoCard | 100.002.458 | ||
KEGG | |||
PubChem CID |
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RTECS number | GR8575000 | ||
UNII | |||
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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)[2] | ||
-89.53·10−6 cm3/mol | |||
Refractive index (nD) |
1.4915 (20 °C) | ||
Viscosity | 0.777 cP (21 °C) | ||
Hazards | |||
Main hazards | flammable | ||
R-phrases (outdated) | R10,R37,R51/53,R65 | ||
S-phrases (outdated) | S24,S37,S61,S62 | ||
NFPA 704 | |||
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): | |||
LD50 (median dose) |
12750 mg/kg (oral, mouse) 1400 mg/kg (oral, rat)[3] | ||
LC50 (median concentration) |
200 ppm (mouse, 7 hr)[3] | ||
LCLo (lowest published) |
8000 ppm (rat, 4 hr)[3] | ||
US health exposure limits (NIOSH): | |||
PEL (Permissible) |
TWA 50 ppm (245 mg/m3) [skin][2] | ||
REL (Recommended) |
TWA 50 ppm (245 mg/m3) [skin][2] | ||
IDLH (Immediate danger) |
900 ppm[2] | ||
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
![](../I/m/Cumene-formation-2D-skeletal_V2.svg.png)
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.[4] 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.[5] The addition of two equivalents of propylene gives diisopropylbenzene (DIPB). Using transalkylation, DIPB is comproportionated with benzene.[6]
Safety
Isopropylbenzene forms peroxides upon contact with air. Tests for peroxides are routinely conducted before heating or distilling.
See also
References
- ↑ Nomenclature of Organic Chemistry : IUPAC Recommendations and Preferred Names 2013 (Blue Book). Cambridge: The Royal Society of Chemistry. 2014. pp. 139, 597. doi:10.1039/9781849733069-FP001. ISBN 978-0-85404-182-4.
- 1 2 3 4 "NIOSH Pocket Guide to Chemical Hazards #0159". National Institute for Occupational Safety and Health (NIOSH).
- 1 2 3 "Cumene". Immediately Dangerous to Life and Health Concentrations (IDLH). National Institute for Occupational Safety and Health (NIOSH).
- ↑ Market Study Benzene, published by Ceresana, July 2011
- ↑ The Innovation Group website, page accessed 15/11/07
- ↑ Bipin V. Vora, Joseph A. Kocal, Paul T. Barger, Robert J. Schmidt, James A. Johnson (2003). "Alkylation". Kirk‐Othmer Encyclopedia of Chemical Technology. doi:10.1002/0471238961.0112112508011313.a01.pub2.