Trimethylamine (TMA) · 30–45% aqueous solution, alcoholic solutions and anhydrous gas
Trimethylamine is the tertiary member of the methylamine family and the standard raw material for quaternary ammonium chemistry. Chelora Amines supplies it worldwide — to choline chloride, betaine, ion-exchange resin, biocide and water-treatment plants across Asia, the Middle East, Africa, Europe and the Americas, as well as throughout India. Packed in carboys, drums, IBC totes or cylinders, shipped in UN-specification packaging with a batch-wise COA and SDS.
36.03 + 9.07 + 14.01 = 59.11 g/mol
Trimethylamine, usually written TMA, is ammonia with all three hydrogens replaced by methyl groups. That makes it a tertiary amine: the nitrogen still carries a lone pair and still acts as a base and a nucleophile, but there is no N–H bond left for anything to attach to. Everything the chemical industry buys it for follows from that one fact.
Pure trimethylamine is a colourless gas at room temperature with an intensely fishy odour detectable at parts per billion, so the practical forms are a solution in water at 30 to 45 percent, a 25–33 percent solution in methanol or ethanol, and anhydrous liquefied gas in cylinders and ISO tanks for continuous plants.
It is manufactured by passing methanol and ammonia over an acidic alumina or zeolite catalyst at 350–500 °C. The reactor produces methylamine, dimethylamine and trimethylamine together, and the three are separated by distillation — which is why the same producers usually supply all three, and why a trimethylamine specification always states the monomethylamine, dimethylamine and free ammonia content.
| Chemical name | Trimethylamine (N,N-dimethylmethanamine) |
| Common synonyms | TMA, tri-methyl amine, N,N,N-trimethylamine |
| CAS number | 75-50-3 |
| EC / EINECS number | 200-875-0 |
| HS / HSN code | 2921 11 (harmonised heading used worldwide; HSN 2921 11 on Indian invoices) |
| Molecular formula | (CH₃)₃N (C₃H₉N) |
| Molecular weight | 59.11 g/mol |
| Appearance | Colourless gas; clear colourless liquid as a solution |
| Odour | Intensely fishy, ammoniacal; detectable at very low concentrations |
| Melting point | −117 °C |
| Boiling point | 2.9 °C (anhydrous) |
| Density | 0.627 g/cm³ (liquefied, 25 °C); about 0.89 g/cm³ for the 40% aqueous solution |
| Vapour pressure | About 1.9–2.2 bar at 20–25 °C (anhydrous) |
| Solubility in water | Very soluble; solubility falls as temperature rises |
| pKa of conjugate acid | 9.81 at 25 °C |
| pH | Strongly alkaline in aqueous solution |
| Flammability limits in air | Approximately 2.0 – 11.6 vol % |
| Auto-ignition temperature | About 190 °C |
| UN number | UN 1083 (anhydrous, Class 2.1); UN 1297 (aqueous solution, Class 3 with subsidiary 8) |
Figures are typical literature values for orientation. Values for the material you order are stated on its Certificate of Analysis and Safety Data Sheet.
One property explains almost everything trimethylamine is used for: the nitrogen has a lone pair but no hydrogen. It attacks electrophiles and it accepts protons, but it cannot be acylated, so the product is a salt or a quaternary ammonium compound rather than an amide.
The headline reaction. Alkyl halides, dimethyl sulfate and epoxides attack the lone pair to give a permanently charged quaternary ammonium salt — the basis of quats, phase-transfer catalysts and cationic surfactants.
(CH₃)₃N + R–X → R(CH₃)₃N⁺X⁻Reaction with ethylene oxide in the presence of hydrochloric acid gives choline chloride in one step. This single outlet accounts for a large share of world trimethylamine consumption.
(CH₃)₃N + EO + HCl → choline chlorideWith monochloroacetic acid under alkaline conditions it gives glycine betaine, a zwitterionic osmolyte used in feed, cosmetics and agricultural biostimulants.
(CH₃)₃N + ClCH₂COOH → betaineNeutralises mineral and organic acids to give water-soluble trimethylammonium salts, used where a soluble base is needed or where the amine is to be released again later by raising the pH.
(CH₃)₃N + HCl → (CH₃)₃NH⁺Cl⁻Reacts with chloromethylated polystyrene beads to install fixed quaternary sites, which is how Type I strong-base anion exchange resin is made for demineralisation plants.
resin–CH₂Cl + (CH₃)₃N → resin–CH₂N⁺(CH₃)₃Oxidation with hydrogen peroxide gives trimethylamine N-oxide, used as an intermediate, a reference standard and a reagent in oxidation and decomplexation chemistry.
(CH₃)₃N + H₂O₂ → (CH₃)₃N⁺–O⁻Acts as a nucleophilic catalyst in urethane, epoxy and ester chemistry, and as a gaseous catalyst in the foundry cold-box process for curing phenolic urethane core binders.
pKa 9.81 at 25 °CWith no N–H bond, trimethylamine does not form amides, ureas, carbamates, imines or sulfonamides. If your step needs any of those, you want methylamine or dimethylamine instead — and we will say so.
no N–H, no acylationProcess notes. Quaternisations are strongly exothermic and usually run under pressure because of the low boiling point, so add trimethylamine under control and keep cooling and relief capacity available. Vent gas carries the odour a very long way, so scrubbing or an acid trap on the vent line is normal practice rather than an optional extra. Where water interferes, move from the aqueous grade to an alcoholic solution or anhydrous gas rather than trying to dry the solution on site.
Discuss your processPractically all commercial trimethylamine comes from the same catalytic route. Knowing how it is made explains why the specification always controls monomethylamine, dimethylamine and free ammonia — they are made in the same reactor.
Methanol and ammonia are vaporised and mixed, with the methanol-to-ammonia ratio set to favour the fully substituted product.
The mixture passes over an amorphous silica-alumina or zeolite catalyst at roughly 350–500 °C and moderate pressure.
The reactor delivers trimethylamine together with methylamine, dimethylamine, unreacted ammonia and water.
A distillation train, including an extractive column that uses water to break the trimethylamine–ammonia azeotrope, splits the three amines. Off-spec cuts are recycled.
Product is dried for anhydrous grade or diluted to strength in water, tested, then filled into carboys, drums, totes or cylinders under nitrogen.
Because all three methylamines leave the reactor together, the real quality question is not simply "how much trimethylamine" but "what else came with it". Residual monomethylamine and dimethylamine still carry N–H bonds, so in a quaternisation they consume alkylating agent and produce tertiary and secondary by-products that end up in your finished quat. Free ammonia does the same, several times over.
This matters most where the product goes into feed, personal care or a resin that has to meet a leachables limit. If your downstream step is sensitive to any of these, say so at enquiry stage and we will match the batch rather than send the standard commercial cut.
In sealed original packing, stored cool and out of sunlight, trimethylamine solutions are normally used within twelve months, and we recommend a re-check of assay and colour after that before a critical batch. The material does not "go off" so much as drift: air and carbon dioxide ingress form carbonate and raise the APHA colour, and repeated opening of a part-used drum is the usual cause.
Keep drums closed between draws, blanket bulk tanks with nitrogen where you can, and avoid storing part-used packs next to a heat source. A retained sample of each batch is held here, so if a consignment is ever queried we can test against the original.
Tell us the reaction and the solvent system and we will confirm the form, strength and grade. Commercial grade covers most production use; LR and AR grades are available for laboratory and analytical work.
The everyday commercial form, most often supplied at 40%. Easy to pump, store and dose, and the normal feed for choline and betaine plants.
Trimethylamine in methanol or ethanol for quaternisations and syntheses where water would hydrolyse the alkylating agent.
Liquefied gas for continuous plants, cold-box foundry use and high-volume quaternisation, in cylinders, tonners and ISO tanks.
Tighter limits on ammonia, monomethylamine and dimethylamine for R&D, method development and QC use.
| Parameter | Test method | Typical specification |
|---|---|---|
| Appearance | Visual | Clear, colourless liquid, free from suspended matter |
| Assay (trimethylamine) | Titration / GC | 39.5 – 40.5 % w/w |
| Dimethylamine | GC | ≤ 0.5 % w/w |
| Monomethylamine | GC | ≤ 0.3 % w/w |
| Free ammonia | GC | ≤ 0.2 % w/w |
| Colour | APHA | ≤ 20 |
| Non-volatile matter | Gravimetric | ≤ 0.05 % w/w |
| Density at 25 °C | Densitometer | 0.885 – 0.900 g/cm³ |
| Iron (Fe) | AAS | ≤ 2 ppm |
Indicative specification for planning. The controlling document is the Certificate of Analysis issued for your batch. If your process needs tighter limits on dimethylamine, monomethylamine or water, say so at enquiry stage and we will quote against your specification.
This is the single most common question at enquiry stage, and the answer is decided by your reaction rather than by price. Use the table to narrow it down, then send us the step you are running and we will confirm.
| Point of comparison | 40% aqueous solution | 25–33% alcoholic solution | Anhydrous liquefied gas |
|---|---|---|---|
| Best suited to | Choline chloride, betaine, cationic polymers, neutralisation and formulations where water is fine | Quaternisations with moisture-sensitive alkylating agents and fine chemical synthesis | Continuous quat plants, resin functionalisation, foundry cold-box catalysis |
| Water content | About 60% by weight | Low, controlled to specification | Essentially none |
| Handling | Pump or gravity decant; ordinary liquid handling with odour control | As for aqueous, plus flammable-solvent controls | Pressure equipment, trained operators, gas detection |
| Storage | Cool, ventilated, bunded, sealed containers | Flammable-liquid store with earthing and bonding | Gas store or bulk tank, pressure-rated and relief-protected |
| Packs | 25 L carboy, 200 kg drum, 1000 L IBC | Carboys and drums | Cylinders, tonners, ISO tanks |
| Amine per kilogram delivered | Lowest — you also pay to move water | Middle | Highest |
| Transport classification | UN 1297, Class 3 with subsidiary 8 | UN 1297 or solvent-dependent, Class 3 with subsidiary 8 | UN 1083, Class 2.1 flammable gas |
Three products, one reactor, very different chemistry. Ordering the wrong one is the most expensive mistake a purchase team can make with this family, and abbreviations are usually how it happens.
| Property | Trimethylamine (TMA) | Dimethylamine (DMA) | Methylamine (MMA) |
|---|---|---|---|
| CAS number | 75-50-3 | 124-40-3 | 74-89-5 |
| Formula | (CH₃)₃N | (CH₃)₂NH | CH₃NH₂ |
| Molecular weight | 59.11 | 45.08 | 31.06 |
| Amine class | Tertiary — no N–H bond | Secondary — one N–H bond free | Primary — two N–H bonds free |
| Boiling point | 2.9 °C | 7.4 °C | −6.3 °C |
| pKa of conjugate acid | 9.81 | 10.73 | 10.66 |
| Typical outlets | Choline chloride, quaternary ammonium compounds, betaines, anion exchange resins | DMF and DMAc solvents, rubber accelerators, water-treatment polymers, surfactants | NMP, carbamate insecticides, N-methyl pharma intermediates, surfactants |
| Can it be further substituted? | No — only quaternised | Yes, once | Yes, twice |
A warning about initials. TMA is also used in the trade for trimellitic anhydride and, occasionally, for trimethylaluminium — three completely different products. The same trap sits elsewhere in the family: TEA can mean triethanolamine or triethylamine, and DEA can mean diethanolamine or diethylamine. Always write the full chemical name with the CAS number on the enquiry and the purchase order.
See the full amine rangeMost trimethylamine consumption sits in one place: choline chloride for animal feed. The rest spreads across quaternary ammonium chemistry, water treatment and specialty intermediates. Here is the full picture, sector by sector.
The raw material for choline chloride, supplied to feed mills as a liquid or on a silica or corn-cob carrier, and for betaine used as an osmolyte and methyl donor in poultry, swine and aquaculture feed.
Alkylated with long-chain halides or dimethyl sulfate to give cationic surfactants, fabric softeners, hair conditioning quats, disinfectants and phase-transfer catalysts.
Used to functionalise Type I strong-base anion exchange resin, and to make cationic flocculants and colour-removal polymers for effluent plants and demineralisation trains.
A base and quaternising agent in bulk drug synthesis, a source of the trimethylammonium group in choline-based APIs and contrast agents, and a reagent in phase-transfer catalysed steps.
Feeds cationic starch and wet-strength resins for paper mills, and quaternary softeners, levelling agents and cationic fixing agents for textile processing houses.
The gaseous catalyst in the amine cold-box process for curing phenolic urethane core binders, and a catalyst and chain modifier in polyurethane and epoxy systems.
Goes into clay stabilisers, corrosion inhibitors, biocidal quats for injection water, and the cationic additives used in drilling and completion fluids.
A reference standard in freshness and spoilage testing, a reagent in trimethylamine N-oxide chemistry, and a laboratory base for quaternisation and phase-transfer work.
If you are mapping a value chain or looking for the product one step down from where you are, this is where trimethylamine ends up. Several of these are chemicals we can also source for you.
| Derivative | Made by | End use |
|---|---|---|
| Choline chloride (CAS 67-48-1) | Reaction with ethylene oxide and hydrochloric acid | Vitamin B4 supplement for poultry, swine and aqua feed; also a clay stabiliser and a component of deep eutectic solvents |
| Glycine betaine (CAS 107-43-7) | Reaction with monochloroacetic acid | Feed osmolyte, methyl donor, cosmetic humectant and crop biostimulant |
| Cationic surfactants and softeners | Alkylation with long-chain halides or dimethyl sulfate | Fabric softeners, hair conditioners, emulsifiers and antistatic agents |
| Quaternary ammonium biocides | Alkylation with benzyl or alkyl chlorides | Disinfectants, sanitisers, algaecides and preservative systems |
| Type I anion exchange resin | Amination of chloromethylated polystyrene | Demineralisation, condensate polishing, sugar and pharmaceutical purification |
| Cationic starch and wet-strength resins | Quaternisation of epoxide-functional intermediates | Paper making, retention aids and board strength |
| Trimethylamine hydrochloride (CAS 593-81-7) | Neutralisation with hydrochloric acid | Solid, easy-to-weigh reagent for laboratory and synthesis use |
| Trimethylamine N-oxide | Oxidation with hydrogen peroxide | Intermediate, analytical standard and oxidation reagent |
| Tetramethylammonium salts | Alkylation with methyl chloride or dimethyl sulfate | Electronics developers and etchants, phase-transfer catalysts, electrolytes |
| Carnitine and choline-based intermediates | Multi-step synthesis from choline chemistry | Nutraceuticals, infant formula additives and pharmaceutical actives |
Looking for one of these rather than the amine itself? Ask us — several are within our sourcing network, and we can quote the derivative and the raw material together.
Every container carries the Chelora Amines label with product name, strength, net weight, batch number, manufacturing date, UN number and hazard pictograms.
HDPE carboys for lab qualification, pilot batches and low-consumption users.
HDPE and MS drums for the aqueous and alcoholic solutions — the most common pack.
Forklift-ready totes with bottom valves for plants drawing trimethylamine every week.
Anhydrous trimethylamine in pressure cylinders, tonners and ISO tanks for continuous plants.
Share your monthly consumption, the solvent your process uses and your storage setup, and we will recommend the form, pack size and delivery schedule that keeps your plant running without excess inventory. Export consignments are packed in UN-specification containers, palletised and stretch-wrapped, and shipped FOB, CIF or CFR through Nhava Sheva and Mundra.
Plan my supplyTrimethylamine is a flammable, corrosive base with a low boiling point and an odour threshold in the parts per billion. The notes below are a summary for planning only — always work to the Safety Data Sheet supplied with your consignment and your own site risk assessment.
Trimethylamine is a regulated product in transport and, in several countries, subject to end-use checks. Both are routine for us, but they shape what we need from you before a first shipment moves.
| Item | Aqueous solution | Anhydrous |
|---|---|---|
| Proper shipping name | Trimethylamine, aqueous solution | Trimethylamine, anhydrous |
| UN number | UN 1297 | UN 1083 |
| Hazard class | Class 3, subsidiary risk 8 | Class 2.1 flammable gas |
| Packing group | Depends on concentration; typically II | Not applicable to gases |
| Labels | Flame and corrosion pictograms | Flame pictogram, gas cylinder marking |
| Modes | Road, sea (IMDG) and air subject to quantity limits | Road and sea; air movement heavily restricted |
| Segregation | Away from acids, oxidisers, halogens and hypochlorites | Away from oxidising and flammable-gas cylinders per site rules |
Where trimethylamine goes into feed or food-contact chains, the paperwork requirement usually goes beyond transport: buyers ask for origin statements, GMO and allergen declarations and sometimes a specification signed against their own document. Tell us at enquiry stage which of these your quality system needs, and they are prepared with the consignment rather than chased after it has shipped.
Start account opening| Parameter | Specification | Result |
|---|---|---|
| Appearance | Clear, colourless liquid | Complies |
| Assay (GC) | 39.5 – 40.5 % | Complies |
| Dimethylamine | ≤ 0.5 % | Complies |
| Free ammonia | ≤ 0.2 % | Complies |
| Colour (APHA) | ≤ 20 | Complies |
Trimethylamine is checked before dispatch and each consignment leaves with the paperwork your QC, stores and accounts teams need on day one.
The numbers on a Certificate of Analysis are only useful if you know how they were produced. These are the methods behind the figures on ours, and the checks worth repeating at your own goods-inward.
Separates trimethylamine from dimethylamine, monomethylamine and ammonia in one run, and gives the assay and the impurity profile that matter most to a quaternisation.
An independent check on total amine content, useful as a quick goods-inward confirmation before a drum is released to production.
Water determination for anhydrous and alcoholic grades, where the water number is often the reason the grade was chosen in the first place.
A visual platinum–cobalt comparison. A rising colour value is the earliest sign that a pack has been exposed to air or held too long.
Fast confirmation that the solution strength is what the label says, and a simple way to spot dilution or the wrong pack.
Gravimetric residue and trace metal checks, which matter for catalytic steps and for any product going into a regulated formulation.
A sample from every dispatched batch is held here, so a query months later can be settled against the original material rather than an argument.
Batch number on the label ties back to the COA, the test record and the supply lot, which is what your auditor will ask to see.
Where your customer or regulator needs an independent result, we can arrange analysis at a NABL-accredited laboratory before dispatch.
Five steps for a first order of trimethylamine. Repeat orders follow the same route on a schedule that matches your consumption.
Form and strength, grade, quantity, pack size and delivery location.
We confirm the form for your solvent system and quote, usually within 24 hours.
The batch is tested and the COA, SDS and invoice details are prepared.
Labelled packs move by road, or in UN-spec packaging for export.
Material reaches your gate and repeat dispatches are scheduled to your usage.
Trimethylamine is a commodity on a price list and a headache in a warehouse. What separates suppliers is the form flexibility, the paperwork and the answer you get when something is not routine.
Trimethylamine sits alongside the other methylamines, ethylamines, ethanolamines and fatty amines we supply. Your purchase team raises one enquiry, compares one quote and manages one vendor record instead of six.
Aqueous, alcoholic and anhydrous trimethylamine are all available, so you are not forced to redesign a step around the only grade your supplier happens to carry.
COA, SDS, correct HSN and HS codes, dangerous goods declarations and certificates of origin are prepared with the consignment, not chased afterwards by your logistics team.
Tell us your limits on dimethylamine, monomethylamine, ammonia or water and we quote against them, rather than sending the standard cut and letting your QC department find out.
Once we know your monthly draw we hold and release material on a schedule, so you carry less inventory of a flammable, corrosive product than you otherwise would.
Describe the reaction rather than the product code and we will tell you which form and grade fits — and say so plainly when a different amine would serve you better.
Buyers who order trimethylamine usually source these from the same list. Open any product for its specification, grades and packing, or see the full product range.
Container shipments to buyers on five continents, plus road dispatch inside India. Tell us your country and destination port and we will quote landed terms, transit time and the documentation your customs broker will ask for.
United Arab Emirates, Saudi Arabia, Oman, Qatar, Kuwait, Bahrain, Jordan, Egypt, Morocco, Kenya, Tanzania, Ethiopia, Nigeria, Ghana and South Africa.
Bangladesh, Sri Lanka, Nepal, Pakistan, Vietnam, Thailand, Indonesia, Malaysia, Singapore, the Philippines, South Korea, Japan, Taiwan, Australia and New Zealand.
Germany, the Netherlands, Belgium, France, Italy, Spain, Portugal, Poland, Czechia, the United Kingdom, Ireland, Türkiye, Russia, Ukraine, Kazakhstan and Uzbekistan.
United States, Canada, Mexico, Brazil, Argentina, Chile, Colombia, Peru, Ecuador and the Caribbean, shipped in UN-specification packaging with full DG documentation.
| Incoterms quoted | EXW, FOB, CFR, CIF and DAP, depending on your destination and preference |
| Load ports | Nhava Sheva (JNPT) and Mundra, with Chennai and Kolkata used for eastbound routings |
| Container options | Full container loads, and consolidated LCL shipments for smaller quantities |
| Typical container fill | Around 80 drums of 200 kg, or roughly 18 to 20 IBC totes, in a 20 ft container |
| Packing for export | UN-specification drums and totes, palletised, strapped and stretch-wrapped, with DG labelling |
| Air freight | Possible for small quantities of the solution within dangerous goods limits; anhydrous gas is heavily restricted |
| Payment terms | Advance, irrevocable letter of credit or agreed credit terms for established accounts |
| Before first shipment | Company credentials, end-use declaration and any import permit the destination country requires |
Road dispatch from our Mumbai base to industrial clusters in 16 states and Delhi. Open your state for the local industries we serve and the amines they order most.
Most delays in quoting trimethylamine come from a missing line in the enquiry, not from availability. Send these eight details and a firm price usually comes back the same day.
Not sure of some of it yet? Send what you have. A description of the reaction step and an approximate monthly volume is enough for us to come back with a recommended form, a pack plan and an indicative price.
Send an enquiryPlain definitions of the words that appear on a trimethylamine specification, label and shipping document.
Short answers to what purchase, plant and QC teams ask us most about this product. Anything else, ask us directly.
Send the strength, grade, quantity, pack size and your delivery address or destination port. We come back with a price, the documents that go with the batch and a dispatch or shipping plan, usually within 24 hours.