Acrylonitrile
| |||
| |||
| Names | |||
|---|---|---|---|
| IUPAC names
2-propenenitrile,
prop-2-enenitrile | |||
| Other names | |||
| Identifiers | |||
3D model (JSmol)
|
|||
| ChEBI | |||
| ChEMBL | |||
| ChemSpider | |||
| ECHA InfoCard | 100.003.152 | ||
| EC Number |
| ||
| KEGG | |||
PubChem CID
|
|||
| RTECS number |
| ||
| UNII | |||
| UN number | 1093 | ||
CompTox Dashboard (EPA)
|
|||
| |||
| |||
| Properties | |||
| C3H3N | |||
| Molar mass | 53.064 g·mol−1 | ||
| Appearance | Colourless liquid | ||
| Density | 0.81 g/cm3 | ||
| Melting point | −84 °C (−119 °F; 189 K) | ||
| Boiling point | 77 °C (171 °F; 350 K) | ||
| 70 g/L | |||
| Vapor pressure | 83 mmHg[1] | ||
| Hazards | |||
| Occupational safety and health (OHS/OSH): | |||
Main hazards
|
flammable, reactive, toxic, potential occupational carcinogen[1] | ||
| NFPA 704 (fire diamond) | |||
| Flash point | −1 °C; 30 °F; 272 K | ||
| 471 °C (880 °F; 744 K) | |||
| Explosive limits | 3–17% | ||
| Lethal dose or concentration (LD, LC): | |||
LC50 (median concentration)
|
500 ppm (rat, 4 hr) 313 ppm (mouse, 4 hr) 425 ppm (rat, 4 hr)[2] | ||
LCLo (lowest published)
|
260 ppm (rabbit, 4 hr) 575 ppm (guinea pig, 4 hr) 636 ppm (rat, 4 hr) 452 ppm (human, 1 hr)[2] | ||
| NIOSH (US health exposure limits): | |||
PEL (Permissible)
|
TWA 2 ppm C 10 ppm [15-minute] [skin][1] | ||
REL (Recommended)
|
Ca TWA 1 ppm C 10 ppm [15-minute] [skin][1] | ||
IDLH (Immediate danger)
|
85 ppm[1] | ||
| Safety data sheet (SDS) | ICSC 0092 | ||
| Related compounds | |||
Related compounds
|
acrylic acid, acrolein | ||
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
| |||
Acrylonitrile is an organic compound with the formula CH2CHCN. It is a colorless volatile liquid, although commercial samples can be yellow due to impurities. In terms of its molecular structure, it consists of a vinyl group linked to a nitrile. It is an important monomer for the manufacture of useful plastics such as polyacrylonitrile. It is reactive and toxic at low doses.[3]
Production
Acrylonitrile is produced by catalytic ammoxidation of propylene, also known as the SOHIO process. In 2002, world production capacity was estimated at 5 million tonnes per year.[3][4] Acetonitrile and hydrogen cyanide are significant byproducts that are recovered for sale.[3] In fact, the 2008–2009 acetonitrile shortage was caused by a decrease in demand for acrylonitrile.[5]
In the SOHIO process, propylene, ammonia, and air (oxidizer) are passed through a fluidized bed reactor containing the catalyst at 400–510 °C and 50–200 kPag. The reactants pass through the reactor only once, before being quenched in aqueous sulfuric acid. Excess propylene, carbon monoxide, carbon dioxide, and dinitrogen that do not dissolve are vented directly to the atmosphere, or are incinerated. The aqueous solution consists of acrylonitrile, acetonitrile, hydrocyanic acid, and ammonium sulfate (from excess ammonia). A recovery column removes bulk water, and acrylonitrile and acetonitrile are separated by distillation. Historically, one of the first successful catalysts was bismuth phosphomolybdate supported on silica as a heterogeneous catalyst. Further improvements have since been made.[3]
Historical
Acrylonitrile was first synthesized by the French chemist Charles Moureu (1863–1929) in 1893.[6]
Uses
Acrylonitrile is used principally as a monomer to prepare polyacrylonitrile, a homopolymer, or several important copolymers, such as styrene-acrylonitrile (SAN), acrylonitrile butadiene styrene (ABS), acrylonitrile styrene acrylate (ASA), and other synthetic rubbers such as acrylonitrile butadiene (NBR). Dimerization of acrylonitrile affords adiponitrile, used in the synthesis of certain polyamides. Small amounts are also used as a fumigant. Acrylonitrile and derivatives, such as 2-chloro-acrylonitrile, are dienophiles in Diels-Alder reactions. Acrylonitrile is also a precursor in the industrial manufacture of acrylamide and acrylic acid.[3]
Health effects
Acrylonitrile is highly flammable and toxic at low doses. It undergoes explosive polymerization. The burning material releases fumes of hydrogen cyanide and oxides of nitrogen. It is classified as a Class 2B carcinogen (possibly carcinogenic) by the International Agency for Research on Cancer (IARC),[7] and workers exposed to high levels of airborne acrylonitrile are diagnosed more frequently with lung cancer than the rest of the population.[8] It evaporates quickly at room temperature (20 °C) to reach dangerous concentrations; skin irritation, respiratory irritation, and eye irritation are the immediate effects of this exposure.[9]
Acrylonitrile increases cancer in high dose tests in male and female rats and mice.[10]
Pathways of exposure for humans include emissions, auto exhaust, and cigarette smoke that can expose the human subject directly if they inhale or smoke. Routes of exposure include inhalation, oral, and to a certain extent dermal uptake (tested with volunteer humans and in rat studies).[11] Repeated exposure causes skin sensitization and may cause central nervous system and liver damage.[9]
There are two main excretion processes of acrylonitrile. The primary method is excretion in urine when acrylonitrile is metabolized by being directly conjugated to glutathione. The other method is when acrylonitrile is metabolized with 2-cyanoethylene oxide to produce cyanide end products that ultimately forms thiocyanate, which is excreted via urine, or carbon dioxide and eliminated through the lungs.[11] Metabolites can be detected in the blood and urine.[7]
Acrylonitrile induces apoptosis in human umbilical cord mesenchymal stem cells [12]
Environmental effects
Acrylonitrile is harmful to aquatic life.[9]
References
- ^ a b c d e f g h NIOSH Pocket Guide to Chemical Hazards. "#0014". National Institute for Occupational Safety and Health (NIOSH).
- ^ a b "Acrylonitrile". Immediately Dangerous to Life or Health Concentrations (IDLH). National Institute for Occupational Safety and Health (NIOSH).
- ^ a b c d e James F. Brazdil. "Acrylonitrile". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a01_177.pub3. ISBN 978-3527306732.
- ^ "The Sohio Acrylonitrile Process". American Chemical Society National Historic Chemical Landmarks. Retrieved 2013-05-13.
- ^ A. Tullo. "A Solvent Dries Up". Chemical & Engineering News. 86: 27. doi:10.1021/cen-v086n047.p027.
- ^ See:
- C. Moureu (1893) "Contribution à l'étude de l'acide acrylique et de ses dérivés" (Contribution to the study of acrylic acid and of its derivatives), Annales de chimie et de physique, 7th series, 2 : 145-212 ; see especially pp. 187-189 ("Nitrile acrylique ou cyanure de vinyle (Propène-nitrile)").
- Moureu (1893) "Nitrile acrylique, cyanure de vinyle (propène-nitrile)," Bulletin de la Société chimique de France, 3rd series, 9 : 424-427.
- ^ a b "Re-evaluation of Some Organic Chemicals, Hydrazine and Hydrogen Peroxide". IARC Monographs, Volume 71 (1999)
- ^ Acrylonitrile Fact Sheet (CAS No. 107-13-1). epa.gov
- ^ a b c "CDC - ACRYLONITRILE - International Chemical Safety Cards - NIOSH". www.cdc.gov. Retrieved 2015-07-31.
- ^ "Acrylonitrile: Carcinogenic Potency Database". berkeley.edu.
- ^ a b Acrylonitrile Fact Sheet: Support Document (CAS No. 107-13-1). epa.gov
- ^ Sun X (Jan 2014). "Cytotoxic effects of acrylonitrile on human umbilical cord mesenchymal stem cells in vitro". J Mol Med Rep. 9 (1): 97–102. doi:10.3892/mmr.2013.1802. PMID 24248151.
External links
- National Pollutant Inventory – Acrylonitrile
- Comparing Possible Cancer Hazards from Human Exposures to Rodent Carcinogens
- Acrylonitrile – Integrated Risk Information System, U.S. Environmental Protection Agency
- CDC – NIOSH Pocket Guide to Chemical Hazards – Acrylonitrile
- OSHA Table Z-1 for Air Contaminants
