Chemical Properties
Triethanolamine is a pale yellow and viscous liquid. It is hygroscopic with an irritant and ammoniacal odor. There are multiple industrial and domestic applications for this compound, i.e., in the manufacture of toilet products, cosmetics formulations, solvents for waxes, resins, dyes, paraffi ns and polishes, herbicides, and lubricants for textile products. In the pharmaceutical industry, triethanolamine is used as a non-steroidal, antiinfl ammatory agent, an emulsifi er, and an alkylating agent.
Definition
ChEBI: Triethanolamine is a tertiary amino compound that is ammonia in which each of the hydrogens is substituted by a 2-hydroxyethyl group. It has a role as a buffer and a surfactant. It is a tertiary amino compound, a triol and an amino alcohol. It is functionally related to a triethylamine. It is a conjugate base of a triethanolammonium.
General Description
Oily liquid with a mild ammonia odor. Denser than water. Freezing point is 71°F.
Reactivity Profile
TRIETHANOLAMINE(102-71-6) is an aminoalcohol. Neutralize acids to form salts plus water in exothermic reactions. Amines may be incompatible with isocyanates, halogenated organics, peroxides, phenols (acidic), epoxides, anhydrides, and acid halides. Flammable gaseous hydrogen is generated in combination with strong reducing agents, such as hydrides. Reacts violently with strong oxidants. [Handling Chemicals Safely 1980. p. 928].
Air & Water Reactions
Water soluble.
Health Hazard
Exposures to triethanolamine, in contrast with other chemical compounds, is known to cause low toxicity to animals and the acute oral LD50 to rats and guinea pigs ranges from 8000 to 9000 mg/kg. Triethanolamine was found to be a moderate eye irritant. A 5%–10% solution of triethanolamine did not induce skin irritation or skin sensitization. Studies of Inoue et al. and many other workers have indicated the absence of the mutagenic potential of triethanolamine as evidenced by both in vivo and in vitro studies (Salmonella typhimurium tests, Chinese hamster ovary cells, and rat liver chromosome analysis). Further, extensive studies have demonstrated the absence of potential carcinogenicity of triethanolamine in rats and mice, suggesting a low or lack of acute or chronic toxicity of the chemical to mammals.
Potential Exposure
Monoethanolamine is widely used in
industry for scrubbing acid gases and in production of
detergents and alkanolamide surfactants; to remove carbon dioxide and hydrogen from natural gas, to remove hydrogen
sulfide and carbonyl sulfide; as an alkaline conditioning
agent; as an intermediate for soaps, detergents, dyes, and
textile agents. Diethanolamine is an absorbent for gases; a
solubilizer for 2,4- dichlorophenoxyacetic acid (2,4-D); and
a softener and emulsifier intermediate for detergents. It also
finds use in the dye and textile industry. Triethanolamine is
used as plasticizers, neutralizer for alkaline dispersions;
lubricant additive; corrosion inhibitor; and in the manufacture of soaps, detergents, shampoos, shaving preparations;
face and hand creams; cements, cutting oils, insecticides,
surface active agents; waxes, polishes, and herbicides.
Fire Hazard
Special Hazards of Combustion Products: Poisonous gases, such as NOx, may be produced
First aid
If this chemical gets into the eyes, remove any
contact lenses at once and irrigate immediately for at least
15 minutes, occasionally lifting upper and lower lids. Seek
medical attention immediately. If this chemical contacts the
skin, remove contaminated clothing and wash immediately
with soap and water. Speed in removing material from skin
is of extreme importance. Shampoo hair promptly if contaminated. Seek medical attention immediately. If this
chemical has been inhaled, remove from exposure, begin
rescue breathing (using universal precautions, including
resuscitation mask) if breathing has stopped and CPR if
heart action has stopped. Transfer promptly to a medical
facility. When this chemical has been swallowed, get medical attention. Give large quantities of water and induce
vomiting. Do not make an unconscious person vomit
Shipping
UN2491 Ethanol
amine or Ethanolamine solutions, Hazard class: 8; Labels: 8-Corrosive material.
Incompatibilities
Monoethanolamine: This chemical is a
medium-strong base. Reacts violently with strong oxidizers,
acetic acid; acetic anhydride; acrolein, acrylic acid; acrylonitrile, cellulose nitrate; chlorosulfonic acid; epichlorohydrin, hydrochloric acid; hydrogen fluoride; mesityl oxide;
nitric acid; oleum, sulfuric acid; β-propiolactone; and vinyl
acetate. Reacts with iron. May attack copper, aluminum,
and their alloys, and rubber. Di-isomer: Oxidizers, strong
acids; acid anhydrides; halides. Reacts with CO2 in the air.
Hygroscopic (i.e., absorbs moisture from the air). Corrosive
to copper, zinc, and galvanized iron (di-). The aqueous
solution is a medium strong base. Attacks copper, zinc,
aluminum, and their alloys.
Waste Disposal
Controlled incineration; incinerator equipped with a scrubber or thermal unit to reduce
nitrogen oxides emissions
Preparation
Triethanolamine is prepared commercially by the ammonolysis of ethylene oxide. The reaction yields a mixture of monoethanolamine, diethanolamine, and triethanolamine, which are separated to obtain the pure products.
Production Methods
Triethanolamine is produced with ethanolamine and diethanolamine by ammonolysis
of ethylene oxide and the triethanolamine is then separated by distillation
(Mullins 1978). In 1984, 139.6 million pounds of triethanolamine were produced
in the United States (USTIC 1985).
Brand name
Mobisyl [as salicylate] (Ascher);Sabrilex.
Composition
The dried leaves contain protein, 25.7%; fat, 6.5%; carbohydrate, 40.8%; ash, 5%; caffeine, 3.3% and tannin, 13%. The most common catechins are gallic esters (epicatechin, epicatechin gallate and epigallocatechin gallate). All are found in green tea and are claimed to be responsible for the chemopreventive benefits of the beverage.
World Health Organization (WHO)
Trolamine is widely used as an emulsifier in combination with
fatty acids in pharmaceutical and cosmetic products. The World Health Organization is not aware of restrictive action having been taken elsewhere.
Flammability and Explosibility
Nonflammable
Chemical Reactivity
Reactivity with Water No reaction; Reactivity with Common Materials: No reactions; Stability During Transport: Stable; Neutralizing Agents for Acids and Caustics: Dilute with water; Polymerization: Not pertinent; Inhibitor of Polymerization: Not pertinent.
Pharmaceutical Applications
Triethanolamine(102-71-6) is widely used in topical pharmaceutical formulations, primarily in the formation of emulsions.
When mixed in equimolar proportions with a fatty acid, such as stearic acid or oleic acid, triethanolamine forms an anionic soap with a pH of about 8, which may be used as an emulsifying agent to produce fine-grained, stable oil-in-water emulsions. Concentrations that are typically used for emulsification are 2–4% v/v of triethanolamine and 2–5 times that of fatty acids. In the case of mineral oils, 5% v/v of triethanolamine will be needed, with an appropriate increase in the amount of fatty acid used. Preparations that contain triethanolamine soaps tend to darken on storage. However, discoloration may be reduced by avoiding exposure to light and contact with metals and metal ions.
Triethanolamine is also used in salt formation for injectable solutions and in topical analgesic preparations. It is also used in sun screen preparations.
Triethanolamine is used as an intermediate in the manufacturing of surfactants, textile specialties, waxes, polishes, herbicides, petroleum demulsifiers, toilet goods, cement additives, and cutting oils. Triethanolamine is also claimed to be used for the production of lubricants for the rubber gloves and textile industries. Other general uses are as buffers, solvents, and polymer plasticizers, and as a humectant.
Industrial uses
Triethanolamine undergoes reactions characteristic of tertiary amines and of
alcohols. Two industrially important reactions of the ethanolamines involve
reaction with carbon dioxide or hydrogen sulfide to yield water soluble salts, and
reaction with long chain fatty acids to form neutral ethanolamine soaps (Mullins
1978). Substituted ethanolamine compounds, such as soaps, are used extensively
as emulsifiers, thickeners, wetting agents, and detergents in cosmetic formulations
(including skin cleaners, creams, and lotions) (Beyer et al 1983).
The largest uses for triethanolamine are in the production of fatty acid soaps and
detergents and in cosmetic formulations. In cosmetics, triethanolamine is an
important raw material and is used in combination with fatty acids as emulsifiers
for creams, lotions, skin cleaners, and shampoos. Triethanolamine is also used in
cement and concrete to reduce particle agglomeration within the grinding mill; as
an antistatic agent in the textile industry; in the metal industry for metal plating
and in alkaline derusting formulations; in the rubber industry as a vulcanization
accelerator; and in the manufacture of herbicides and pesticides. Triethanolamine
may also be used as a surface active agent in cutting fluids; as an absorption agent
for acidic gases in air pollution control; as a component of coating on fruits and
vegetables; as a solvent for casein, shellac, and dyes; and as a penetrating agent for
organic liquids in wood and paper (Bayer et al 1983; Mullins 1978; Windholz
1983). Triethanolamine is permitted in articles intended for use in the production,
processing, or packaging of food (CFR 1981).
Safety
Triethanolamine is used primarily as an emulsifying agent in a
variety of topical pharmaceutical preparations. Although generally
regarded as a nontoxic material, triethanolamine may cause
hypersensitivity or be irritant to the skin when present in formulated
products. The lethal human oral dose of triethanolamine is
estimated to be 5–15 g/kg body-weight.
Following concern about the possible production of nitrosamines
in the stomach, the Swiss authorities have restricted the use of
triethanolamine to preparations intended for external use.
LD50 (guinea pig, oral): 5.3 g/kg
LD50 (mouse, IP): 1.45 g/kg
LD50 (mouse, oral): 7.4 g/kg
LD50 (rat, oral): 8 g/kg
Carcinogenicity
Results of carcinogenicity
studies have been controversial. Hoshino and Tanooka reported that triethanolamine in the diet of mice at levels
of 0.03% or 0.3% caused a significant increase in the
occurrence of tumors, both benign and malignant. Females
showed a 32% increase, mostly of thymic lymphomas. The
increase of all other tumors, in both sexes, was 8.2%. They
also found that triethanolamine reacted with sodium nitrite
to produce N-nitrosodiethanolamine and that the product
caused mutagenesis in bacteria. Maekawa et al.
reported that no carcinogenic activity was found when
given orally to rats in drinking water at concentrations of
1% and 2% for 2 years. However, the dosage to
females was halved after week 69 of treatment owing to
nephrotoxicity. Histological examination of renal damage
in treated animals revealed acceleration of chronic
nephropathy, mineralization of the renal papilla, nodular
hyperplasia of the pelvic mucosa, and pyelonephritis with
or without papillary necrosis. Nephrotoxicity seemed to
affect life span adversely, especially in females. Tumor
incidence and histology were the same in the treated group
as in controls.
storage
Triethanolamine may turn brown on exposure to air and light.
The 85% grade of triethanolamine tends to stratify below 15℃;
homegeneity can be restored by warming and mixing before use.
Triethanolamine should be stored in an airtight container
protected from light, in a cool, dry place.
See Monoethanolamine for further information.
Purification Methods
Shake the amine gently with Linde type 4A molecular sieves for 24hours, filter and fractionate it under a vacuum, and preferably in the presence of N2. Store it in dark stoppered bottles under N2 as it is hygroscopic, and turns brown in air and light. It has a strong ammoniacal odour (like diethanolamine). It is miscible with H2O, MeOH and Me2CO, and its solubilities at 25o in n-heptane, Et2O and *C6H6 are 0.4%, 1.6% and 4.2%, respectively. [See diethanolamine above, Beilstein 4 IV 1524.]
Regulatory Status
Included in the FDA Inactive Ingredients Database (rectal, topical,
and vaginal preparations). Included in nonparenteral medicines licensed in the UK. Included in the Canadian List of Acceptable
Non-medicinal Ingredients.
