Ethanolamine
Names | |
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Preferred IUPAC name
2-Aminoethan-1-ol[1] | |
Other names
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Identifiers | |
3D model (
JSmol ) |
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ChEBI | |
ChEMBL | |
ChemSpider | |
DrugBank | |
ECHA InfoCard
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100.004.986 |
EC Number |
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KEGG | |
PubChem CID
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RTECS number
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UNII | |
CompTox Dashboard (EPA)
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Properties | |
C2H7NO | |
Molar mass | 61.084 g·mol−1 |
Appearance | Viscous colourless liquid |
Odor | Unpleasant ammonia-like odour |
Density | 1.0117 g/cm3 |
Melting point | 10.3 °C (50.5 °F; 283.4 K) |
Boiling point | 170 °C (338 °F; 443 K) |
Miscible | |
Vapor pressure | 64 Pa (20 °C)[2] |
Acidity (pKa) | 9.50[3] |
Refractive index (nD)
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1.4539 (20 °C)[4] |
Hazards | |
GHS labelling: | |
Danger | |
H302, H312, H314, H332, H335, H412[5] | |
P261, P273, P303+P361+P353, P305+P351+P338[5] | |
NFPA 704 (fire diamond) | |
Flash point | 85 °C (185 °F; 358 K) (closed cup) |
410 °C (770 °F; 683 K) | |
Explosive limits
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5.5–17% |
Lethal dose or concentration (LD, LC): | |
LD50 (median dose)
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NIOSH (US health exposure limits): | |
PEL (Permissible)
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TWA: 3 ppm (6 mg/m3)[6] |
REL (Recommended)
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IDLH (Immediate danger) |
30 ppm[6] |
Safety data sheet (SDS) | Sigma[5] |
Related compounds | |
Related compounds
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Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Ethanolamine (2-aminoethanol, monoethanolamine, ETA, or MEA) is a naturally occurring
Ethanolamine is commonly called monoethanolamine or MEA in order to be distinguished from
Ethanolamine in Nature
ETA molecules are a component in the formation of cellular membranes and are thus a molecular building block for life. Ethanolamine is the second-most-abundant head group for phospholipids, substances found in biological membranes (particularly those of prokaryotes); e.g., phosphatidylethanolamine. It is also used in messenger molecules such as palmitoylethanolamide, which has an effect on CB1 receptors.[11]
ETA was thought to exist only on Earth and on certain asteroids, but in 2021 evidence was found that ETA molecules exist in interstellar space.[12]
Ethanolamine is biosynthesized by decarboxylation of serine:[13]
- HOCH
2CH(CO
2H)NH
2 → HOCH
2CH
2NH
2 + CO2
Derivatives of ethanolamine are widespread in nature; e.g., lipids, as precursor of a variety of N-acylethanolamines (NAEs), that modulate several animal and plant physiological processes such as seed germination, plant–pathogen interactions, chloroplast development and flowering,[14] as well as precursor, combined with arachidonic acid C
20H
32O
2 20:4, ω-6), to form the endocannabinoid anandamide (AEA: C
22H
37NO
2; 20:4, ω-6).[15]
ETA is biodegraded by ethanolamine ammonia-lyase, a B12-dependent enzyme. It is converted to acetaldehyde and ammonia via initial H-atom abstraction.[16]
- H2NCH2CH2OH → NH3 + CH3CHO
Industrial production
Monoethanolamine is produced by treating ethylene oxide with aqueous ammonia; the reaction also produces diethanolamine and triethanolamine. The ratio of the products can be controlled by the stoichiometry of the reactants.[17]
Applications
MEA is used as
For example, reacting ethanolamine with
Gas stream scrubbing
Monoethanolamines can scrub combusted-coal, combusted-methane and combusted-biogas flue emissions of carbon dioxide (CO2) very efficiently. MEA carbon dioxide scrubbing is also used to regenerate the air on submarines.
Solutions of MEA in
MEA scrubbing solutions can be recycled through a regeneration unit. When heated, MEA, being a rather weak base, will release dissolved H2S or CO2 gas resulting in a pure MEA solution.[17][20]
Other uses
In pharmaceutical formulations, MEA is used primarily for buffering or preparation of emulsions. MEA can be used as pH regulator in cosmetics.[21]
It is an injectable
It is also an ingredient in cleaning fluid for automobile windshields.[22]
pH-control amine
Ethanolamine is often used for alkalinization of water in steam cycles of power plants, including nuclear
Reactions
Upon reaction with carbon dioxide, 2 equivalents of ethanolamine react through the intermediacy of carbonic acid to form a carbamate salt,[23] which when heated reforms ethanolamine and carbon dioxide.
References
- ^ ISBN 978-0-85404-182-4.
For example, the name 'ethanolamine', which is still widely used, is badly constructed because of the presence of two suffixes; it is not an alternative to the preferred IUPAC name, '2-aminoethan-1-ol'.
- ^ "Ethanolamine MSDS" (PDF). Acros Organics. Archived from the original (PDF) on 2011-07-15.
- .
- .
- ^ a b c Sigma-Aldrich Co., Ethanolamine. Retrieved on 2018-05-24.
- ^ a b c NIOSH Pocket Guide to Chemical Hazards. "#0256". National Institute for Occupational Safety and Health (NIOSH).
- ^ "Ethanolamine". Immediately Dangerous to Life or Health Concentrations (IDLH). National Institute for Occupational Safety and Health (NIOSH).
- ^ "National Library of Medicine. PubChem. Ethanolomine". NIH, National Library of Medicine. Retrieved September 5, 2021.
- ^ ISBN 978-3527306732.
- ^ Cough, Cold, and Allergy Preparation Toxicity at eMedicine
- PMID 11426841.
- ^ "First evidence of cell membrane molecules in space". Astronomy Magazine. May 28, 2021. Retrieved September 4, 2021.
- ^ "Phosphatidylethanolamine and related lipids". AOCS. Archived from the original on 2012-08-21. Retrieved 2015-08-09.
- PMID 30190434.
- PMID 8670178.
- PMID 20519496.
- ^ ISBN 3-527-30578-5.
- hdl:10044/1/25382.
- ISBN 978-0-309-09225-8.
- Occupational Safety & Health Administration. Archived from the originalon 2013-05-03. Retrieved 2008-05-11.
- ISBN 978-84-613-4979-1.
- ^ Federal Motor Vehicle Safety Standards. U.S. Department of Transportation, National Highway Traffic Safety Administration. 1994. p. Part 571; S 108—PRE 128.
- .