Triethanolamine

Key takeaways

Triethanolamine belongs to chemistry; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect Triethanolamine to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of Triethanolamine from memory before moving on to harder problems.

Reference excerpt

Triethanolamine (TEOA) is an organic compound with the chemical formula N(CH2CH2OH)3. It is a colourless, viscous liquid. It is both a tertiary amine and a triol. A triol is a molecule with three alcohol groups. Approximately 150,000 tonnes were produced in 1999. It is a colourless compound although samples may appear yellow because of impurities.

Production Triethanolamine is produced from the reaction of ethylene oxide with aqueous ammonia, also produced are ethanolamine and diethanolamine. The ratio of the products can be controlled by changing the stoichiometry of the reactants.

Applications Triethanolamine is used primarily in making surfactants, such as for emulsifiers. It is a common ingredient in formulations used for both industrial and consumer products. The triethanolamine neutralizes fatty acids, adjusts and buffers the pH, and solubilizes oils and other ingredients that are not completely soluble in water. Triethanolammonium salts in some cases are more soluble than salts of alkali metals that might be used otherwise, and results in less alkaline products than would from using alkali metal hydroxides to form the salt. Some common products in which triethanolamine is found are sunscreen lotions, liquid laundry detergents, dishwashing liquids, general cleaners, hand sanitizers, polishes, metalworking fluids, paints, shaving cream and printing inks.

Cement production Triethanolamine is also used as organic additive (0.1 wt%) in the grinding of cement clinker. It facilitates the grinding process by preventing agglomeration and coating of the powder at the surface of balls and mill wall.

Cosmetics and medicine Various ear diseases and infections are treated with eardrops containing triethanolamine polypeptide oleate-condensate, such as Cerumenex in the United States. In pharmaceutics, triethanolamine is the active ingredient of some eardrops used to treat impacted earwax. It also serves as a pH balancer in many different cosmetic products, ranging from cleansing creams and milks, skin lotions, eye gels, moisturizers, shampoos, shaving foams, TEOA is a fairly strong base: a 1% solution has a pH of approximately 10, whereas the pH of skin is less than pH 7, approximately 5.5−6.0. Cleansing milk–cream emulsions based on TEOA are particularly good at removing makeup.

Derivatives Amustaline Trolnitrate Trimustine

In the laboratory and in amateur photography Another common use of TEOA is as a complexing agent for aluminium ions in aqueous solutions. This reaction is often used to mask such ions before complexometric titrations with another chelating agent such as EDTA. TEOA has also been used in photographic (silver halide) processing. It has been promoted as a useful alkali by amateur photographers.

In holography TEOA is used to provide a sensitivity boost to silver-halide-based holograms, and also as a swelling agent to color shift holograms. It is possible to get the sensitivity boost without color shift by rinsing out the TEOA before squeegee and drying.

In electroless plating TEOA is now commonly and very effectively used as a complexing agent in electroless deposition.

In ultrasonic testing 2-3% in water TEOA is used as an corrosion inhibitor (anti-rust) agent in immersion ultrasonic testing.

In aluminium soldering Triethanolamine, diethanolamine and aminoethylethanolamine are major components of common liquid organic fluxes for the soldering of aluminium alloys using tin-zinc and other tin or lead-based soft solders.

Safety and regulation

Allergic reactions A 1996 study found that triethanolamine (TEOA) occasionally causes contact allergy. A 2001 study found TEOA in a sunscreen caused an allergic contact dermatitis. A 2007 study found TEOA in ear drops caused a contact allergy. Systemic and respiratory tract (RT) toxicity was analyzed for 28 days in a nose specific inhalation 2008 study in Wistar rats; TEOA seems to be less potent in regard to systemic toxicity and RT irritancy than diethanolamine (DEA). Exposure to TEOA resulted in focal inflammation, starting in single male animals from 20 mg/m3 concentrations. A 2009 study stated that patch test reactions reveal a slight irritant potential instead of a true allergic response in several cases, and also indicated the risk of skin sensitization to TEOA seems to be very low.

Tumors Reports indicated that TEOA causes an increased incidence of tumor growth in the liver in female B6C3F1 mice, but not in male mice or in Fischer 344 rats, although higher-primates are known to have higher resistance to the tumorigenesis. A 2004 study concluded "TEOA may cause liver tumors in mice via a choline-depletion mode of action and that this effect is likely caused by the inhibition of choline uptake by cells."

Environmental toxicity A 2009 study found that TEOA has potential acute, sub-chronic and chronic toxicity properties in respect to aquatic species.

Regulation TEOA is listed under Schedule 3, part B of the Chemical Weapons Convention as it can be used in the manufacture of HN3 nitrogen mustard.

See also Complexometric titration Ethanolamine Ethanol Triethanolamine salicylate

References

Illustrations

Worked examples

Example 1 — a first encounter with Triethanolamine

Start with the simplest possible case. Write down what Triethanolamine claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In chemistry, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Triethanolamine before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Triethanolamine ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Triethanolamine

In research: Triethanolamine appears in chemistry research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses Triethanolamine in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: Triethanolamine is common in secondary-school and first-year university syllabi. It links to neighbouring topics Concrete admixtures, Cosmetics chemicals, Excipients, so understanding it makes those chapters shorter.
In everyday life: Look for Triethanolamine outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

How to study Triethanolamine in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Triethanolamine means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain Triethanolamine out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Triethanolamine in simple terms?

Triethanolamine (TEOA) is an organic compound with the chemical formula N(CH2CH2OH)3. It is a colourless, viscous liquid.

Why does Triethanolamine matter?

Because it connects several chemistry ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Triethanolamine?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Triethanolamine.