Triethylene Glycol CAS 112-27-6
Chelora Chemicals supplies industrial-grade triethylene glycol to gas processing, humectant, plasticiser and air-treatment users worldwide. Every consignment leaves with a batch-specific COA covering purity, water, glycol distribution and colour, the current SDS and full export documentation.
Also known as: TEG · Triglycol · 2,2′-(Ethylenedioxy)diethanol · Trigen
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Price, lead time and a sample COA for Triethylene Glycol, usually within one working day. We ship worldwide.
Request a Quote Email the DeskDocumentation
- Batch-specific COA (purity, water, glycol distribution, colour)
- Safety Data Sheet (SDS)
- Transport and export documents
- Third-party inspection on request
- Certificate of origin
What is Triethylene Glycol?
Triethylene glycol is the third member of the ethylene glycol series, C₆H₁₄O₄, a clear, colourless, odourless and viscous liquid with very low volatility and strong water affinity.
Like DEG it is a co-product of ethylene glycol manufacture, formed when MEG and DEG react further with ethylene oxide.
Its dominant use is natural gas dehydration. TEG absorbs water from gas in a contactor tower and can be regenerated to high concentration, achieving the low water dew points pipeline specifications demand.
Beyond gas processing, TEG serves as a humectant, a plasticiser intermediate, a vinyl and polyurethane component, and as an air disinfectant in some specialist applications.
Why Triethylene Glycol specifically
- The highest regeneration purity. TEG can be regenerated above 98.5%, which is what makes very low gas dew points achievable.
- Very low vapour pressure. Minimal carry-over losses into the dried gas compared with lighter glycols.
- Strong hygroscopicity. Absorbs water aggressively, which is precisely the property gas dehydration requires.
- Thermally robust to about 200 °C. Tolerates the reboiler temperatures needed for high-purity regeneration.
How Triethylene Glycol is Manufactured
TEG is produced alongside MEG and DEG in ethylene oxide hydration, then separated by vacuum distillation.
- Ethylene oxide hydration. EO reacts with water and with the glycols already formed, producing a MEG, DEG and TEG mixture.
- Water ratio control. Lower water ratios increase the share of heavier glycols including TEG.
- Evaporation. Excess water is removed in the multi-effect evaporator train.
- Vacuum distillation. The glycols are separated by boiling point, with TEG taken as a heavier cut than DEG.
- Finishing. Final distillation controls colour, water and tetraethylene glycol carry-over.
- Specialty purification. Higher-purity grades for humectant and specialty use receive additional treatment.
Typical Commercial Specification
Figures below are representative of commercial industrial-grade TEG for gas dehydration. Specialty and high-purity grades carry tighter limits — tell us the use and we will send the matching sheet.
| Parameter | Typical Value |
|---|---|
| Appearance | Clear colourless liquid, free of suspended matter |
| TEG purity | 99.0% min by weight |
| Water content | 0.1% max |
| Diethylene glycol | To grade, typically 0.5% max |
| Tetraethylene glycol | To grade, typically 0.5% max |
| Acidity (as acetic acid) | To grade, typically 10 ppm max |
| Ash content | To grade, typically 50 ppm max |
| Iron | To grade, typically 0.5 ppm max |
| Colour (Pt-Co) | 15 max |
| Specific gravity at 20/20 °C | 1.1240 to 1.1270 |
Physical & Chemical Properties
| Property | Value |
|---|---|
| Chemical formula | C₆H₁₄O₄ |
| Molecular weight | 150.17 g/mol |
| Appearance | Clear colourless viscous liquid, practically odourless |
| Boiling point | 285 °C |
| Melting point | −7 °C |
| Flash point | About 177 °C (closed cup) |
| Density | 1.125 g/cm³ at 20 °C |
| Viscosity | About 49 mPa·s at 20 °C |
| Vapour pressure | Extremely low, under 0.001 kPa at 20 °C |
| Solubility in water | Completely miscible |
| Thermal decomposition | Begins around 206 °C |
| Hygroscopicity | Strongly hygroscopic |
| Incompatibilities | Strong oxidisers, strong acids and bases at high temperature |
Behaviour in the process
TEG's properties are chosen for circulating service, and its behaviour there is well characterised:
- Regenerates to high purity. Reboiler temperatures around 200 °C give lean glycol above 98.5%, and stripping gas pushes it higher still.
- Degrades above about 206 °C. Overheating in the reboiler produces acids and degradation products that corrode and foam.
- Foams with contamination. Hydrocarbon condensate, corrosion inhibitors and surfactants all cause foaming in the contactor.
- Viscous when cold. At 49 mPa·s it is noticeably thicker than MEG; cold-weather pumping needs allowance.
TEG and Alternative Dehydration Glycols
Glycol selection for dehydration is a trade-off between achievable dew point, regeneration temperature and cost.
| Material | Origin / type | When it is the right choice |
|---|---|---|
| Triethylene glycol | C₆ ether diol, 99%+ | The industry standard for natural gas dehydration |
| Diethylene glycol | C₄ ether diol, CAS 111-46-6 | Lower cost, lower regeneration purity, less dew point depression |
| Tetraethylene glycol | C₈ ether diol, CAS 112-60-7 | Very high temperature gas streams; higher cost and viscosity |
| Mono ethylene glycol | C₂ diol, CAS 107-21-1 | Hydrate inhibition by injection rather than absorption dehydration |
| Molecular sieves | Solid adsorbent | Where very low water content is required, as ahead of cryogenic processing |
Stated plainly: TEG is the default for pipeline gas dehydration because it hits the right balance of dew point depression, regeneration temperature and cost. Molecular sieves beat it on dryness but cost far more to install and run.
Industries We Supply Triethylene Glycol To
Gas processing dominates, with humectant, plasticiser and specialty uses behind it.
Where Triethylene Glycol is Used
Natural gas dehydration accounts for the largest share of TEG, with plasticisers, polyurethanes and humectant uses behind it.
In natural gas dehydration
Wet gas contacts lean TEG in a trayed or packed tower; the glycol absorbs water and is then regenerated by heating to about 200 °C. Lean glycol concentration determines the achievable dew point, and the practical limits come from reboiler temperature — too low and the glycol stays wet, too high and it degrades. Stripping gas and enhanced regeneration schemes push concentration higher where very dry gas is required.
Contamination and foaming
Most TEG system problems are contamination rather than glycol quality: hydrocarbon condensate, well treatment chemicals, corrosion products and salt all cause foaming, carry-over and loss. Filtration, carbon beds and inlet separation do more for glycol consumption than changing supplier ever will.
Need a specific grade, purity and packing format?
Tell us the grade, the purity and water limits your dehydration or formulation requires, the packing format you can receive and the annual quantity. We will come back with a price, a lead time, a sample COA and the full documentation set.
Quality Control & Testing
Every lot is released against a batch-specific Certificate of Analysis, with water and glycol distribution reported because both affect achievable dew point.
- TEG purity and water content — by gas chromatography and Karl Fischer titration.
- DEG and tetraethylene glycol content — reported because carry-over shifts the boiling range and regeneration behaviour.
- Acidity — measured because it rises with thermal degradation and drives corrosion.
- Iron and ash — reported as contamination and corrosion indicators.
- Colour — confirming freedom from degradation and contamination.
- Specific gravity — confirming identity and concentration.
Common Process Problems & Likely Causes
When TEG causes trouble, it is usually contamination, reboiler temperature or water carry-over. This table is the shortcut our technical desk works through before anyone opens a complaint file.
| Symptom | Likely cause | What to check |
|---|---|---|
| Gas dew point not meeting specification | Lean glycol concentration too low | Water content, reboiler temperature and stripping gas rate |
| Foaming and carry-over in the contactor | Hydrocarbon or chemical contamination in the glycol | Inlet separation, filtration and carbon bed condition |
| High glycol losses | Carry-over, degradation or reboiler overheating | Reboiler temperature against the 206 °C degradation point |
| Acidity rising in the circulating glycol | Thermal degradation or oxygen ingress | Acidity trend, blanketing and reboiler control |
| Corrosion in the regeneration section | Acidic degradation products and chlorides | Acidity and chloride results, pH control |
| Dark colour in the circulating glycol | Degradation products and iron pick-up | Colour and iron figures, filtration performance |
Packaging, Storage & Shipping
- Standard packing. 200 L drums, 1000 L IBCs, flexitanks, ISO tank containers and bulk parcel cargoes.
- Moisture control. TEG is strongly hygroscopic; keep containers sealed and use dry breathers, since water arriving with the glycol costs dew point directly.
- Material compatibility. Carbon steel is normal in gas plant service; stainless is preferred for specialty grades where colour matters.
- Temperature. Ambient storage; viscosity rises substantially in cold weather, so size pumps and lines for winter conditions.
- Storage. Clean, dry, covered storage with bunding; not a flammable-liquid hazard in normal handling.
- Segregation. Keep apart from strong oxidisers and acids, and away from food and pharmaceutical materials.
- Shelf life. Typically 24 months in sealed storage. Water content and colour are the practical checks.
- Transport classification. Not classified as dangerous goods for transport.
Hazards & Safe Handling
TEG has low acute toxicity and is not classified as dangerous goods, but hot glycol in regeneration systems presents a real burn hazard and degraded glycol can be acidic.
- Low acute toxicity. TEG is among the least toxic of the glycols and is not classified as harmful in most jurisdictions. It should still not be ingested.
- Hot glycol. Regeneration systems operate near 200 °C. Thermal burns from hot glycol are the most realistic injury in TEG service.
- Degraded glycol. Acidic degradation products in used glycol are more aggressive to skin and equipment than fresh material.
- Low flammability. Flash point about 177 °C; not a flammable-liquid hazard in ordinary handling, though it will burn in a fire.
- Skin and eye contact. Mild irritant; use gloves and eye protection for routine handling, and heat-resistant gloves for hot service.
- Confined spaces. Glycol systems in gas plants can accumulate hydrocarbon vapour; apply confined space procedures during maintenance.
- Environment. Biodegradable but causes oxygen depletion at volume; contain spills and used glycol for proper disposal.
Regulatory & Compliance Notes
TEG is unregulated for transport and widely used, with application-specific rules in gas processing and air treatment. The notes below are orientation rather than legal advice.
- GHS classification. Not classified as hazardous in most jurisdictions; the SDS carries any applicable statements.
- Transport. Not classified as dangerous goods. Standard bulk and packaged cargo documentation applies.
- Gas processing emissions. BTEX and VOC emissions from glycol regeneration units are regulated in many jurisdictions and drive still-vent control design.
- Biocidal use. Where TEG is used as an air disinfectant, biocidal product registration requirements may apply.
- REACH and inventories. Registered under EU REACH and listed on the major chemical inventories.
- Waste glycol. Used dehydration glycol may be classified as hazardous waste because of absorbed hydrocarbons and BTEX.
We Supply Triethylene Glycol Worldwide
Chelora Chemicals is a supplier and export partner, not a single-plant trader. We ship Triethylene Glycol from India and from partner sources to customers across Asia, Europe, the Middle East, Africa, and North and South America, handling the export documentation, transport paperwork and freight so the material arrives ready to use.
- Incoterms. EXW, FOB, CIF, CFR and DAP quoted to suit your purchasing terms and freight arrangements.
- Ports. Regular shipments through Nhava Sheva (JNPT) and Mundra, with other ports arranged where routing and cargo rules allow.
- Documentation. Commercial invoice, packing list, certificate of origin, COA, SDS and the transport declaration issued as a complete set.
- Flexible volumes. From a pallet of drums up to repeat bulk shipments on a supply contract.
- Supply continuity. Because we are independent of any one producer, a plant turnaround or a shipping disruption at one source does not have to become your stock-out.
Buying Triethylene Glycol from Chelora
We are an independent sourcing and supply partner. For TEG that means settling three things at enquiry: the purity and water content your dehydration system needs, the packing format for your receiving setup, and whether the charge is a full system fill or routine make-up.
- Documentation on every lot. Batch-specific COA (purity, water, glycol distribution, colour), plus SDS and the full transport paperwork.
- Analysis before commitment. Representative analysis shared ahead of a commercial order so your lab can qualify the material.
- Quantities. From a pallet of drums through to full bulk shipments on contract supply.
- Grade matching. Industrial or specialty grade to the purity, water and glycol distribution limits your dehydration or formulation requires.
- Inspection. Independent third-party inspection available at loading when the contract requires it.
- Related products. Mono Ethylene Glycol, Diethylene Glycol, Mono Propylene Glycol and other feedstocks alongside Triethylene Glycol from one supplier.
How ordering works
- Send the enquiry. Product, grade or purity, quantity, destination port and the Incoterm you buy on. If you have a spec sheet, attach it — it saves a round trip.
- We quote. Price, lead time, packing format and a sample COA, normally within one working day.
- Qualify the supply. For first orders or critical applications, we share the analysis and handling documentation so your technical and safety teams can sign off before you commit.
- Confirm the order. Proforma invoice issued; payment terms agreed against the volume and the relationship.
- Allocation and QC. Material allocated and released against a batch-specific COA, with an independent inspection where the contract calls for it.
- Ship and document. Filled, labelled and loaded with the full export document set, and tracked through to arrival.
Triethylene Glycol — Common Questions
The questions our technical desk is asked most often about Triethylene Glycol. If yours isn't here, call or email and you will reach someone who knows the chemistry.
What is the CAS number of triethylene glycol?
The CAS number for TEG is 112-27-6, and its EC number is 203-953-2. Its molecular formula is C₆H₁₄O₄ with a molecular weight of 150.17 g/mol, and it is classified under HS code 2909.49.
What is TEG used for?
Mainly for natural gas dehydration, where it absorbs water from gas in contactor towers. It also serves as a plasticiser intermediate, a polyurethane and vinyl component, a humectant in inks and adhesives, and an air disinfectant in specialist applications.
Do you supply TEG worldwide?
Yes. Chelora Chemicals supplies and exports TEG worldwide — across Asia Pacific, Europe, the Middle East, Africa and the Americas, as well as throughout India, in drums, IBCs, flexitanks, ISO tanks and bulk.
Why is TEG the standard for gas dehydration?
Because it can be regenerated above 98.5% at practical reboiler temperatures, which gives the dew point depression pipeline specifications require, while its very low vapour pressure keeps carry-over losses into the dried gas small.
How is TEG manufactured?
As a co-product of ethylene glycol manufacture. When ethylene oxide is hydrated, successive reactions produce DEG and TEG alongside MEG, and the glycols are separated by vacuum distillation.
What temperature can TEG be regenerated at?
Reboiler temperatures around 200 °C are normal. Thermal decomposition begins near 206 °C, so the operating window is narrow and overheating is the main cause of glycol degradation and loss.
Is TEG hazardous?
It has low acute toxicity and is not classified as dangerous goods for transport. The realistic hazards are thermal burns from hot glycol in regeneration systems and the acidity of degraded glycol.
What is the difference between DEG and TEG?
TEG has an extra oxyethylene unit, a higher boiling point and higher regeneration purity. For gas dehydration that means TEG achieves lower dew points; DEG costs less but dries less effectively.
Why does my glycol system foam?
Almost always contamination rather than glycol quality: liquid hydrocarbon condensate, well treatment chemicals, corrosion products or salt carried into the contactor. Inlet separation and filtration are the fixes.
How should TEG be stored?
In clean, dry, sealed containers or tanks with dry breathers, since TEG is strongly hygroscopic and water arriving with the glycol costs dew point performance directly.
What packing sizes and order quantities are available?
200 L drums, 1000 L IBCs, flexitanks, ISO tank containers and bulk parcel cargoes. Orders run from a pallet of drums up to full system charges and bulk cargoes.
What is the typical shelf life?
Around 24 months in sealed storage. Water content and colour are the practical checks, since TEG picks up moisture readily from humid air.
Ready to source Triethylene Glycol?
Send us your specification, grade and annual volume. You will get a price, a realistic lead time and a sample COA from someone who understands what the material has to do in your process — delivered anywhere in the world.