Diethanolamine

Pure diethanolamine is a white solid at room temperature, but its tendencies to absorb water and to supercool often results in it being found in a colorless, viscous liquid state. Diethanolamine is polyfunctional, being a secondary amine and a diol. Like other organic amines, diethanolamine acts as a weak base. Reflecting the hydrophilic character of the secondary amine and hydroxyl groups, DEA is soluble in water. Amides prepared from DEA are often also hydrophilic. In 2013, the chemical was classified by the International Agency for Research on Cancer as "possibly carcinogenic to humans" (Group 2B).

Diethanolamine

Names
Preferred IUPAC name 2,2′-Azanediyldi(ethan-1-ol)
Other names Bis(hydroxyethyl)amine N,N-Bis(2-hydroxyethyl)amine 2,2'-Dihydroxydiethylamine β,β'-Dihydroxydiethylamine Diolamine 2-[(2-Hydroxyethyl)amino]ethanol 2,2'-Iminobisethanol Iminodiethanol Di(2-hydroxyethyl)amine bis(2-Hydroxyethyl)amine 2,2'-Iminodiethanol
Identifiers
CAS Number	111-42-2 Y
3D model (JSmol)	Interactive image
3DMet	B01050
Beilstein Reference	605315
ChEBI	CHEBI:28123 Y
ChEMBL	ChEMBL119604 Y
ChemSpider	13835604 Y
ECHA InfoCard	100.003.517
EC Number	203-868-0
KEGG	D02337 Y
MeSH	diethanolamine
PubChem CID	8113
RTECS number	KL2975000
UNII	AZE05TDV2V Y
CompTox Dashboard (EPA)	DTXSID3021932
InChI InChI=1S/C4H11NO2/c6-3-1-5-2-4-7/h5-7H,1-4H2 Y Key: ZBCBWPMODOFKDW-UHFFFAOYSA-N Y
SMILES OCCNCCO
Properties
Chemical formula	C4H11NO2
Molar mass	105.137 g·mol−1
Appearance	Colourless crystals
Odor	Ammonia odor
Density	1.097 g·mL−1
Melting point	28.00 °C; 82.40 °F; 301.15 K
Boiling point	271.1 °C; 519.9 °F; 544.2 K
Solubility in water	Miscible
log P	-1.761
Vapor pressure	<1 Pa (at 20 °C)
UV-vis (λmax)	260 nm
Refractive index (nD)	1.477
Thermochemistry
Heat capacity (C)	137 J·K−1·mol−1
Std enthalpy of formation (ΔfH⦵298)	−496.4 – −491.2 kJ·mol−1
Std enthalpy of combustion (ΔcH⦵298)	−26.548 – −26.498 MJ·kmol−1
Hazards
GHS labelling:
Pictograms
Signal word	Danger
Hazard statements	H302, H315, H318, H373
Precautionary statements	P280, P305+P351+P338
Flash point	138 °C (280 °F; 411 K)
Autoignition temperature	365 °C (689 °F; 638 K)
Explosive limits	1.6–9.8%
Lethal dose or concentration (LD, LC):
LD50 (median dose)	120 mg·kg−1 (intraperitoneal, rat) 710 mg·kg−1 (oral, rat) 778 mg·kg−1 (intravaneous, rat) 12.2 g·kg−1 (dermal, rabbit)
NIOSH (US health exposure limits):
PEL (Permissible)	None
REL (Recommended)	TWA: 3 ppm (15 mg/m3)
IDLH (Immediate danger)	N.D.
Safety data sheet (SDS)	sciencelab.com
Related compounds
Related alkanols	N-Methylethanolamine Dimethylethanolamine Diethylethanolamine N,N-Diisopropylaminoethanol Methyl diethanolamine Triethanolamine Bis-tris methane Meglumine
Related compounds	Diethylhydroxylamine
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Y verify (what is YN ?) Infobox references

The reaction of ethylene oxide with aqueous ammonia first produces ethanolamine:

C₂H₄O + NH₃ → H₂NCH₂CH₂OH

which reacts with a second and third equivalent of ethylene oxide to give DEA and triethanolamine:

C₂H₄O + H₂NCH₂CH₂OH → HN(CH₂CH₂OH)₂
C₂H₄O + HN(CH₂CH₂OH)₂ → N(CH₂CH₂OH)₃

About 300M kg are produced annually in this way. The ratio of the products can be controlled by changing the stoichiometry of the reactants.

DEA is used as a surfactant and a corrosion inhibitor. It is used to remove hydrogen sulfide and carbon dioxide from natural gas.

Diethanolamine is widely used in the preparation of diethanolamides and diethanolamine salts of long-chain fatty acids that are formulated into soaps and surfactants used in liquid laundry and dishwashing detergents, cosmetics, shampoos and hair conditioners. In oil refineries, a DEA in water solution is commonly used to remove hydrogen sulfide from sour gas. It has an advantage over a similar amine, ethanolamine, in that a higher concentration may be used for the same corrosion potential. This allows refiners to scrub hydrogen sulfide at a lower circulating amine rate with less overall energy usage.

DEA is a chemical feedstock used in the production of morpholine.

Amides derived from DEA and fatty acids, known as diethanolamides, are amphiphilic.

The reaction of 2-chloro-4,5-diphenyloxazole with DEA gave rise to ditazole. The reaction of DEA and isobutyraldehyde with water removed produces an oxazolidine.

DEA is used in the production of diethanolamides, which are common ingredients in cosmetics and shampoos added to confer a creamy texture and foaming action. Consequently, some cosmetics that include diethanolamides as ingredients contain DEA. Some of the most commonly used diethanolamides include:

• Cocamide DEA
• DEA-Cetyl Phosphate
• DEA Oleth-3 Phosphate
• Lauramide DEA
• Myristamide DEA
• Oleamide DEA

DEA is a potential skin irritant in workers sensitized by exposure to water-based metalworking fluids. One study showed that DEA inhibits in baby mice the absorption of choline, which is necessary for brain development and maintenance; however, a study in humans determined that dermal treatment for 1 month with a commercially available skin lotion containing DEA resulted in DEA levels that were "far below those concentrations associated with perturbed brain development in the mouse". In a mouse study of chronic exposure to inhaled DEA at high concentrations (above 150 mg/m³), DEA was found to induce body and organ weight changes, clinical and histopathological changes, indicative of mild blood, liver, kidney and testicular systemic toxicity. A 2009 study found that DEA has potential acute, chronic and subchronic toxicity properties for aquatic species.