Ethylbenzene
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Names | |||
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Preferred IUPAC name
Ethylbenzene | |||
Other names
Ethylbenzol; Phenylethane; alpha-Methyltoluene; EB
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Identifiers | |||
3D model (
JSmol ) |
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Abbreviations | EB | ||
1901871 | |||
ChEBI | |||
ChEMBL | |||
ChemSpider | |||
DrugBank | |||
ECHA InfoCard
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100.002.591 | ||
KEGG | |||
PubChem CID
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RTECS number
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UNII | |||
CompTox Dashboard (EPA)
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Properties | |||
C8H10 | |||
Molar mass | 106.168 g·mol−1 | ||
Appearance | colorless liquid | ||
Odor | aromatic[1] | ||
Density | 0.8665 g/mL | ||
Melting point | −95 °C (−139 °F; 178 K) | ||
Boiling point | 136 °C (277 °F; 409 K) | ||
0.015 g/100 mL (20 °C) | |||
log P | 3.27 | ||
Vapor pressure | 9.998 mmHg | ||
-77.20·10−6 cm3/mol | |||
Refractive index (nD)
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1.495 | ||
Viscosity | 0.669 cP at 20 °C | ||
0.58 D[2] | |||
Thermochemistry | |||
Heat capacity (C)
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1.726 J/(gK) | ||
Hazards | |||
Occupational safety and health (OHS/OSH): | |||
Main hazards
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Flammable | ||
GHS labelling: | |||
Danger | |||
H225, H304, H320, H332, H335, H336, H351, H360, H373, H400, H411 | |||
P201, P202, P210, P233, P240, P241, P242, P243, P260, P261, P264, P271, P273, P280, P281, P301+P310, P303+P361+P353, P304+P312, P304+P340, P305+P351+P338, P308+P313, P312, P314, P331, P337+P313, P370+P378, P391, P403+P233, P403+P235, P405, P501 | |||
NFPA 704 (fire diamond) | |||
Flash point | 22.22 °C (72.00 °F; 295.37 K) | ||
430 °C (806 °F; 703 K) | |||
Explosive limits
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1–7.8% | ||
Lethal dose or concentration (LD, LC): | |||
LD50 (median dose)
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5460 mg/kg | ||
LCLo (lowest published)
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4000 ppm (rat, 4 hr)[3] | ||
NIOSH (US health exposure limits): | |||
PEL (Permissible)
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TWA 100 ppm (435 mg/m3)[1] | ||
REL (Recommended)
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TWA 100 ppm (435 mg/m3) ST 125 ppm (545 mg/m3)[1] | ||
IDLH (Immediate danger) |
800 ppm[1] | ||
Related compounds | |||
Related
aromatic hydrocarbons |
styrene, toluene | ||
Related compounds
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benzene polystyrene | ||
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Ethylbenzene is an
Occurrence and applications
Ethylbenzene occurs naturally in coal tar and petroleum.[4]
The dominant application of ethylbenzene is its role as an intermediate in the production of polystyrene. Catalytic dehydrogenation of ethylbenzene gives hydrogen and styrene:
- C
6H
5CH
2CH
3 → C6H5CH=CH2 + H
2
As of May 2012, more than 99% of all the ethylbenzene produced is used for this purpose.
Ethylbenzene hydroperoxide, a reagent and radical initiator, is produced by autoxidation of ethylbenzene:
- C6H5CH2CH3 + O2 → C6H5CH(O2H)CH3
Niche uses
Ethylbenzene is added to gasoline as an
Production
Ethylbenzene is produced on a large scale by combining
- C
6H
6 + C
2H
4 → C
6H
5CH
2CH
3
In 2012, more than 99% of ethylbenzene was produced in this way.[citation needed]
Small amounts of ethylbenzene are recovered from the mix of
In the 1980s a zeolite-based process using vapor phase alkylation offered a higher purity and yield. Then a liquid phase process was introduced using
Industrial accidents
On June 3, 2014, an explosion occurred in the Dutch Moerdijk industrial area. This happened in a chemical reactor operated by Shell which overheated due to an exothermal runaway reaction between the metal oxide catalyst and ethylbenzene.[7]
Health effects
The acute toxicity of ethylbenzene is low, with an LD50 of about 4 grams per kilogram of body weight. The longer term toxicity and carcinogenicity is ambiguous.[8] Eye and throat sensitivity can occur when high level exposure to ethylbenzene in the air occurs. At higher level exposure, ethylbenzene can cause dizziness.[4] Once inside the body, ethylbenzene biodegrades to 1-phenylethanol, acetophenone, phenylglyoxylic acid, mandelic acid, benzoic acid and hippuric acid.[8] Ethylbenzene exposure can be determined by testing for the breakdown products in urine.
As of September 2007, the United States
Ethylbenzene is classified as a possible carcinogen by the International Agency for Research on Cancer (IARC) however, the EPA has not determined ethylbenzene to be a carcinogen. The National Toxicology Program conducted an inhalation study in rats and mice. Exposure to ethylbenzene resulted in an increased incidence of kidney and testicular tumors in male rats, and trends of increased kidney tumors in female rats, lung tumors in male mice, and liver tumors in female mice.
As with all organic compounds, ethylbenzene vapors form an explosive mixture with air.
Environmental effects
Ethylbenzene is found mostly as a vapor in the air since it can easily move from water and soil.
As of 2012, according to the EU Dangerous Substances Directive, ethylbenzene is not classified as hazardous to the environment.[5]
Ethylbenzene is a constituent of tobacco smoke.[11]
Biodegradation
Certain strains of the fungus
References
- ^ a b c d NIOSH Pocket Guide to Chemical Hazards. "#0264". National Institute for Occupational Safety and Health (NIOSH).
- ^ Lange's Handbook of Chemistry (15th ed.). 1999.
- ^ "Ethyl benzene". Immediately Dangerous to Life or Health Concentrations (IDLH). National Institute for Occupational Safety and Health (NIOSH).
- ^ a b c d e f g "Ethylbenzene ToxFAQs" (PDF). Agency for Toxic Substances and Disease Registry. Retrieved 21 May 2018.
- ^ a b c d "ETHYLBENZENE : ENVIRONMENTAL, HEALTH & SAFETY GUIDELINES". CEFIC. Archived from the original on 19 September 2014. Retrieved 14 February 2013.
- ^ "Ethylbenzene (EB) Production and Manufacturing Process". PIERS. Retrieved 14 February 2013.
- ^ Summary shell moerdijk onderzoeksraad.nl July 2018
- ^
- ^ "Technology Transfer Network Air Toxics Web Site: Ethylbenzene". US Environmental Protection Agency. Retrieved 13 February 2013.
- ^ "Ethylbenzene". eco-usa.net. Archived from the original on 25 December 2012. Retrieved 12 February 2013.
- PMID 21556207.
- .
- PMID 7710331.
- National Toxicology Program. Toxicology and Carcinogenesis Studies of Ethylbenzene (CAS No. 100-41-4) in F344/N Rats and B6C3F1 Mice (Inhalation Studies). TR No. 466. U.S. Department of Health and Human Services, Public Health Service, National Institutes of Health, Bethesda, MD. 1999.