Cumene

Cumene

Names
Preferred IUPAC name (Propan-2-yl)benzene[1]
Other names Isopropylbenzene Cumol (1-Methylethyl)benzene
Identifiers
CAS Number	98-82-8 Y
3D model (JSmol)	Interactive image
Beilstein Reference	1236613
ChEBI	CHEBI:34656 Y
ChEMBL	ChEMBL1398949
ChemSpider	7128 Y
ECHA InfoCard	100.002.458
EC Number	202-704-5
KEGG	C14396 Y
PubChem CID	7406
RTECS number	GR8575000
UNII	8Q54S3XE7K Y
UN number	1918
CompTox Dashboard (EPA)	DTXSID1021827
show InChI InChI=1S/C9H12/c1-8(2)9-6-4-3-5-7-9/h3-8H,1-2H3 Y Key: RWGFKTVRMDUZSP-UHFFFAOYSA-N Y InChI=1/C9H12/c1-8(2)9-6-4-3-5-7-9/h3-8H,1-2H3 Key: RWGFKTVRMDUZSP-UHFFFAOYAJ
show SMILES CC(C)c1ccccc1
Properties
Chemical formula	C9H12
Molar mass	120.195 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)
Solubility in water	negligible
Solubility	soluble in acetone, ether, ethanol
Vapor pressure	8 mm (20°C)[2]
Magnetic susceptibility (χ)	-89.53·10−6 cm3/mol
Refractive index (nD)	1.4915 (20 °C)
Viscosity	0.777 cP (21 °C)
Hazards
Main hazards	flammable
GHS pictograms
GHS Signal word	Warning
GHS hazard statements	H226, H302, H304, H312, H314, H332, H335, H341, H412, H441
GHS precautionary statements	P201, P202, P260, P261, P264, P270, P271, P273, P280, P281, P301+312, P301+330+331, P302+352, P303+361+353, P304+312, P304+340, P305+351+338, P308+313, P310, P312, P321, P322, P330, P363, P405
NFPA 704 (fire diamond)	2 3 1
Flash point	43 °C (109 °F; 316 K)
Autoignition temperature	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]
NIOSH (US health exposure limits):
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).
Y  (what is YN ?)
Infobox references

Cumene (isopropylbenzene) is 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.^[4] The original route for manufacturing of cumene was by alkylation of benzene in the liquid phase using sulfuric acid as a catalyst, but because of the complicated neutralization and recycling steps required, together with corrosion problems, this process has been largely replaced. As an alternative, 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] In this process, the efficiency of cumene production is generally 70-75%. The remaining components are primarily polyisopropyl benzenes. In 1976, an improved cumene process that uses aluminum chloride as a catalyst was developed. The overall conversion of cumene for this process can be as high as 90%.

The addition of two equivalents of propylene gives diisopropylbenzene (DIPB). Using transalkylation, DIPB is comproportionated with benzene.^[6]

Safety[]

Cumene forms peroxides upon long exposure to air.^[7] Tests for peroxides are routinely conducted before heating or distilling.

References[]

External links[]

• National Pollutant Inventory - Cumene fact sheet
• Cumene Production from Benzene and Propylene Using Aluminum Chloride Catalyst