Ethanolamine
[CAS 141-43-5]

Identification

• Classification: Organic raw materials >> Alcohols, phenols, phenolic compounds and derivatives >> Halogenated, sulfonated, nitrated or nitrosated derivatives of alcohols
• Name: Ethanolamine
• Synonyms: 2-Aminoethanol; 2-Aminoethyl alcohol
• Molecular Formula: C₂H₇NO
• Molecular Weight: 61.08
• Protein Sequence: G
• CAS Registry Number: 141-43-5
• EC Number: 205-483-3
• SMILES: C(CO)N

Properties

• Density: 1.0$+/-$0.1 g/cm³ Calc.^*, 1.012 g/mL (Expl.)
• Melting point: 10 - 11 $degree$C (Expl.)
• Boiling point: 170.9 $degree$C 760 mmHg (Calc.)^*, 170 $degree$C (Expl.)
• Flash point: 93.3 $degree$C (Calc.)^*, 91 $degree$C (Expl.)
• Solubility: Miscible (Expl.)
• Index of refraction: 1.435 (Calc.)^*, 1.454 (Expl.)

^* Calculated using Advanced Chemistry Development (ACD/Labs) Software.

Safety Data

• Hazard Symbols: GHS05;GHS07 Danger
• Risk Statements: H302-H312-H314-H332
• Safety Statements: P260-P261-P264-P270-P271-P280-P301+P317-P301+P330+P331-P302+P352-P302+P361+P354-P304+P340-P305+P354+P338-P316-P317-P321-P330-P362+P364-P363-P405-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Acute toxicity	Acute Tox.	4	H302
Acute toxicity	Acute Tox.	4	H312
Acute toxicity	Acute Tox.	4	H332
Skin corrosion	Skin Corr.	1B	H314
Specific target organ toxicity - single exposure	STOT SE	3	H335
Chronic hazardous to the aquatic environment	Aquatic Chronic	3	H412
Serious eye damage	Eye Dam.	1	H318
Substances or mixtures corrosive to metals	Met. Corr.	1	H290
Skin corrosion	Skin Corr.	1A	H314
Eye irritation	Eye Irrit.	2	H319
Flammable liquids	Flam. Liq.	4	H227
Acute toxicity	Acute Tox.	3	H331
Specific target organ toxicity - repeated exposure	STOT RE	2	H373
Specific target organ toxicity - single exposure	STOT SE	1	H370
Respiratory sensitization	Resp. Sens.	1	H334
Skin sensitization	Skin Sens.	1	H317
Acute hazardous to the aquatic environment	Aquatic Acute	2	H401
Acute toxicity	Acute Tox.	4	H311

• Transport Information: UN 2491

Discovery and Applications

Ethanolamine is a simple organic compound that contains both an amine and an alcohol functional group. Its chemical formula is C₂H₇NO, and it is structurally the simplest member of the amino alcohol class. The molecule consists of a two-carbon chain bearing a primary amino group (–NH₂) and a hydroxyl group (–OH), which gives it both basic and hydrophilic properties.

The structure of ethanolamine can be represented as HO–CH₂–CH₂–NH₂. The presence of both functional groups allows it to participate in hydrogen bonding and to act as both a weak base (via the amine group) and a weak acid (via the hydroxyl group). This dual functionality contributes to its high solubility in water and polar solvents.

Ethanolamine occurs naturally in biological systems as a component of phospholipids. It is a key building block in the synthesis of phosphatidylethanolamine, one of the major phospholipids in cell membranes. In this context, ethanolamine is incorporated into lipid structures that contribute to membrane fluidity, curvature, and biological function. It is also involved in metabolic pathways related to membrane biosynthesis and cellular signaling.

The compound was first identified in the context of lipid chemistry and biological extracts during early studies of cell membrane composition. As biochemical techniques advanced in the 20th century, ethanolamine was recognized as an essential component of phospholipid metabolism and a precursor in the Kennedy pathway, which is responsible for the biosynthesis of phosphatidylethanolamine and phosphatidylcholine.

Industrial production of ethanolamine is typically carried out by the reaction of ethylene oxide with ammonia. This process yields a mixture of ethanolamine, diethanolamine, and triethanolamine, with the distribution depending on reaction conditions and stoichiometry. Ethanolamine is then separated and purified for use in various applications.

Ethanolamine has widespread industrial and commercial uses. It is used as a chemical intermediate in the production of surfactants, detergents, emulsifiers, and corrosion inhibitors. Its ability to neutralize acidic gases makes it useful in gas treatment processes, particularly for removing carbon dioxide and hydrogen sulfide from industrial gas streams. In such applications, ethanolamine forms reversible salts with acidic gases, allowing regeneration and reuse of the solvent.

In addition, ethanolamine is used in formulations for personal care products, pharmaceuticals, and agricultural chemicals. Its amphiphilic nature makes it suitable for stabilizing emulsions and adjusting pH in complex formulations. It also serves as a starting material for the synthesis of more complex organic compounds, including amino alcohol derivatives and chelating agents.

From a biochemical perspective, ethanolamine plays an important role in cellular metabolism. It is involved in the synthesis and remodeling of membrane phospholipids, and its metabolic derivatives are linked to signaling pathways and lipid homeostasis. Disruptions in ethanolamine metabolism can affect membrane integrity and cellular function.

Overall, ethanolamine is a fundamental amino alcohol with both biological and industrial significance. Its simple structure, combining an amine and an alcohol group, underlies its versatility as a building block in biochemistry and as a widely used intermediate in chemical manufacturing.

References

2026. A complete set of canonical nucleobases in the carbonaceous asteroid (162173) Ryugu. Nature Astronomy.
DOI: 10.1038/s41550-026-02791-z

2026. Optimization of a green bipropellant with monoethanolamine, 2-propanol, and hydrogen peroxide 90 wt% as oxidizer. Brazilian Journal of Chemical Engineering.
DOI: 10.1007/s43153-025-00637-1

2026. A Review on Carbon Dioxide Mitigation and Sustainable Energy Production Through Algal Biorefineries. BioEnergy Research.
DOI: 10.1007/s12155-025-10955-4