Mono Ethylene Glycol CAS 107-21-1
Chelora Chemicals supplies fibre-grade and industrial-grade mono ethylene glycol to polyester, antifreeze, coolant and resin producers worldwide. Every consignment leaves with a batch-specific COA covering purity, water, UV transmittance and iron, the current SDS and full export documentation.
Also known as: MEG · Ethylene glycol · 1,2-Ethanediol · Glycol · Monoethylene glycol
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Price, lead time and a sample COA for Mono Ethylene Glycol, usually within one working day. We ship worldwide.
Request a Quote Email the DeskDocumentation
- Batch-specific COA (purity, water, UV transmittance, iron)
- Safety Data Sheet (SDS)
- Transport and export documents
- Third-party inspection on request
- Certificate of origin
What is Mono Ethylene Glycol?
Mono ethylene glycol is the simplest diol, C₂H₆O₂, a clear, colourless, odourless, viscous liquid that is completely miscible with water and freezes only in combination with it.
It is made by hydrating ethylene oxide, either thermally with excess water or catalytically, and it is produced in the same complexes that make the oxide.
Polyester is the dominant outlet. MEG reacts with terephthalic acid to make PET for bottles, fibre and film, and that single chain takes most of global production. Antifreeze, coolant, deicing fluid and unsaturated polyester resins take the rest.
MEG is not classified as dangerous for transport, but it is acutely toxic by ingestion, with a sweet taste that has caused many accidental and deliberate poisonings.
Why Mono Ethylene Glycol specifically
- Two hydroxyl groups. Reacts at both ends to build linear polyester chains with terephthalic acid.
- Depresses freezing point sharply. A 50% aqueous solution protects to about −37 °C, which is the basis of engine coolant.
- High boiling, low volatility. Useful as a heat transfer fluid and humectant where water would evaporate.
- Fully water miscible. Simplifies formulation in coolants, deicers and gas dehydration.
How Mono Ethylene Glycol is Manufactured
MEG is made by hydrating ethylene oxide, with the water ratio controlling how much DEG and TEG are co-produced.
- Ethylene oxide feed. EO from the adjacent silver-catalyst oxidation unit is the starting material.
- Thermal hydration. EO and a large excess of water react at about 150 to 200 °C without catalyst, giving mainly MEG.
- Catalytic hydration. Modern units use a catalyst to improve MEG selectivity at a much lower water ratio and energy cost.
- Evaporation. Excess water is removed in a multi-effect evaporator train, which is the main energy consumer.
- Glycol separation. Vacuum distillation separates MEG from the DEG and TEG co-products.
- Finishing. Final distillation and guard beds deliver fibre grade with the UV transmittance polyester producers require.
Typical Commercial Specification
Figures below are representative of commercial fibre-grade MEG. Industrial and coolant grades carry wider limits — tell us the use and we will send the matching sheet.
| Parameter | Typical Value |
|---|---|
| Appearance | Clear colourless liquid, free of suspended matter |
| MEG purity | 99.9% min by weight |
| Water content | 0.08% max |
| Diethylene glycol | To grade, typically 0.05% max |
| Acidity (as acetic acid) | To grade, typically 10 ppm max |
| Aldehydes (as acetaldehyde) | To grade, typically 8 ppm max |
| Iron | To grade, typically 0.1 ppm max |
| Chlorides | To grade, typically 0.5 ppm max |
| UV transmittance at 220 nm | 70% min, fibre grade |
| Colour (Pt-Co) | 5 max |
| Specific gravity at 20/20 °C | 1.1151 to 1.1156 |
Physical & Chemical Properties
| Property | Value |
|---|---|
| Chemical formula | C₂H₆O₂ (HOCH₂CH₂OH) |
| Molecular weight | 62.07 g/mol |
| Appearance | Clear colourless viscous liquid, practically odourless, sweet taste |
| Boiling point | 197.6 °C |
| Melting point | −12.9 °C |
| Flash point | About 111 °C (closed cup) |
| Density | 1.113 g/cm³ at 20 °C |
| Viscosity | About 21 mPa·s at 20 °C |
| Vapour pressure | About 0.007 kPa at 20 °C — very low |
| Solubility in water | Completely miscible |
| Hygroscopicity | Strongly hygroscopic |
| Freezing point depression | 50% aqueous solution protects to about −37 °C |
| Incompatibilities | Strong oxidisers, acids, bases at high temperature |
Behaviour in the process
MEG is stable and easy to handle, with two practical issues that come up repeatedly:
- Hygroscopic. Absorbs water from air readily, which matters where the water specification is tight and in polyester esterification.
- Oxidises slowly to acids. Air exposure at elevated temperature produces glycolic and formic acid, raising acidity and attacking metals.
- Viscous when cold. Pumping and metering slow noticeably below about 10 °C.
- Low volatility. Flash point above 110 °C means it is not a flammable-liquid hazard in normal handling.
Glycol Grades and Alternatives
MEG is bought by grade, and the grade is defined by UV transmittance and trace impurities rather than headline purity.
| Material | Origin / type | When it is the right choice |
|---|---|---|
| Fibre-grade MEG | 99.9%+, UV transmittance specified | Polyester fibre, film and PET resin manufacture |
| Industrial-grade MEG | 99.5%+, wider impurity limits | Antifreeze, coolant, deicing and resin applications |
| Diethylene glycol | C₄ diol, CAS 111-46-6 | Polyester resins, gas dehydration and plasticisers |
| Mono propylene glycol | C₃ diol, CAS 57-55-6 | Where lower toxicity is required, including food and pharmaceutical use |
| Glycerine | Trihydric alcohol, CAS 56-81-5 | Non-toxic antifreeze and humectant applications |
Stated plainly: where toxicity matters — food, pharmaceutical, or any application with human contact — propylene glycol replaces MEG. Where it does not, MEG is cheaper and performs better as a coolant.
Industries We Supply Mono Ethylene Glycol To
Polyester dominates, but MEG reaches automotive, aviation, gas processing and construction too.
Where Mono Ethylene Glycol is Used
Around 90% of MEG goes to polyester. Antifreeze, coolant and deicing fluids take most of the remainder.
In PET manufacture
MEG is esterified with purified terephthalic acid, then polycondensed under vacuum with excess glycol removed to build molecular weight. The UV transmittance specification matters here: trace aldehydes and unsaturates in the glycol show up as yellowness in the finished bottle or fibre, which cannot be corrected downstream.
In antifreeze and coolant
MEG depresses the freezing point and raises the boiling point of water, with a 50% solution protecting to about −37 °C. The inhibitor package, not the glycol, determines coolant life, but glycol purity still matters because acidic degradation products accelerate corrosion.
Need a specific grade, purity and packing format?
Tell us the grade, the grade and whether UV transmittance is part of your specification, 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 UV transmittance reported for fibre grade because it is the specification polyester producers release against.
- MEG purity and water content — by gas chromatography and Karl Fischer titration.
- UV transmittance — measured at 220, 275 and 350 nm for fibre grade.
- Diethylene glycol content — reported because it affects polymer properties.
- Acidity and aldehydes — measured as the characteristic degradation and process impurities.
- Iron and chlorides — reported in ppm for colour and corrosion reasons.
- Colour and specific gravity — confirming identity and freedom from contamination.
Common Process Problems & Likely Causes
When MEG causes trouble, it is usually water pick-up, UV transmittance, iron or acidity. This table is the shortcut our technical desk works through before anyone opens a complaint file.
| Symptom | Likely cause | What to check |
|---|---|---|
| Polyester yellow or hazy | UV transmittance below specification, trace aldehydes | UV transmittance figures on the COA |
| Water content high on arrival | Hygroscopic pick-up from humid air or a wet tank | Water result, tank breather and dryer |
| Esterification rate slower than usual | Water or DEG content in the glycol | Water and DEG figures against the previous COA |
| Coolant corroding engine components | Acidity from degraded glycol or inhibitor depletion | Acidity result and inhibitor package condition |
| Colour in the delivered glycol | Iron pick-up from carbon steel equipment | Iron result and material of construction |
| Pumping difficulty in cold weather | High viscosity below 10 °C | Storage temperature and pump sizing |
Packaging, Storage & Shipping
- Standard packing. 200 L drums, 1000 L IBCs, flexitanks, ISO tank containers and bulk parcel cargoes.
- Moisture control. MEG is strongly hygroscopic; use a desiccant breather or nitrogen blanket where water specification is tight.
- Material compatibility. Stainless steel is preferred for fibre grade. Carbon steel causes iron pick-up that discolours polyester.
- Temperature. Ambient storage is fine; viscosity rises noticeably below 10 °C, so allow for pumping in cold weather.
- Storage. Clean, dry, covered storage; not a flammable-liquid hazard but still requires bunding against spills.
- Segregation. Keep apart from strong oxidisers and strong acids.
- 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
MEG is not a flammable or corrosive hazard in normal handling, but it is acutely toxic by ingestion. Its sweet taste and lack of odour have caused many poisonings, which is why storage security matters.
- Acute oral toxicity. Harmful and potentially fatal if swallowed. Metabolised to oxalic acid, which causes kidney failure. As little as 100 mL can be lethal to an adult.
- Sweet taste. MEG tastes sweet and has no warning odour, which is why accidental and deliberate poisonings are common. Never store it in unlabelled or drinks containers.
- Antidote. Poisoning is treated with fomepizole or ethanol and dialysis. Site medical plans should name the treatment explicitly.
- Repeated exposure. May cause damage to kidneys and central nervous system through prolonged or repeated exposure.
- Low flammability. Flash point above 110 °C; not a flammable-liquid hazard in ordinary handling, but it will burn in a fire.
- Skin and eye contact. Mild irritant; use gloves and eye protection for routine handling.
- Environment. Biodegradable but causes oxygen depletion in watercourses at volume; contain spills.
Regulatory & Compliance Notes
MEG is unregulated for transport but subject to toxicity labelling and, in some markets, consumer product restrictions. The notes below are orientation rather than legal advice.
- GHS classification. Acute toxicity Category 4 by ingestion and STOT RE Category 2 for kidney effects.
- Transport. Not classified as dangerous goods. Standard bulk and packaged cargo documentation applies.
- Consumer product rules. Some jurisdictions require bittering agents in consumer antifreeze to deter accidental ingestion.
- Food contact chains. Where MEG goes into PET packaging, additional purity and food-contact documentation applies down the chain.
- REACH and inventories. Registered under EU REACH and listed on the major chemical inventories.
- Quality agreements. Polyester producers commonly expect documented UV transmittance, iron and DEG limits with change control.
We Supply Mono Ethylene Glycol Worldwide
Chelora Chemicals is a supplier and export partner, not a single-plant trader. We ship Mono Ethylene 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 Mono Ethylene Glycol from Chelora
We are an independent sourcing and supply partner. For MEG that means settling three things at enquiry: whether you need fibre grade with UV transmittance or industrial grade, the iron and water limits your process needs, and the packing format that suits your receiving setup.
- Documentation on every lot. Batch-specific COA (purity, water, UV transmittance, iron), 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. Fibre grade or industrial grade, with the UV transmittance, iron and DEG limits your process requires.
- Inspection. Independent third-party inspection available at loading when the contract requires it.
- Related products. Purified Terephthalic Acid, Diethylene Glycol, Triethylene Glycol and other feedstocks alongside Mono Ethylene 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.
Mono Ethylene Glycol — Common Questions
The questions our technical desk is asked most often about Mono Ethylene Glycol. If yours isn't here, call or email and you will reach someone who knows the chemistry.
What is the CAS number of mono ethylene glycol?
The CAS number for MEG is 107-21-1, and its EC number is 203-473-3. Its molecular formula is C₂H₆O₂ with a molecular weight of 62.07 g/mol, and it is classified under HS code 2905.31.
What is MEG used for?
About 90% goes to polyester — PET bottle resin, fibre and film. The rest goes to engine antifreeze and coolant, aircraft and runway deicing fluid, gas hydrate inhibition, unsaturated polyester resins and heat transfer fluids.
Do you supply MEG worldwide?
Yes. Chelora Chemicals supplies and exports MEG 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.
What is fibre-grade MEG?
The high-purity grade used for polyester, 99.9% minimum with a UV transmittance specification at 220, 275 and 350 nm. The UV test catches trace aldehydes and unsaturates that cause colour in polyester but do not show in ordinary purity analysis.
How is MEG manufactured?
By hydrating ethylene oxide, either thermally with a large excess of water or catalytically at lower water ratio. DEG and TEG are co-produced in the same reaction, and the glycols are separated by vacuum distillation.
Is MEG hazardous?
It is not classified as dangerous goods for transport and is not flammable in normal handling, but it is acutely toxic by ingestion. It tastes sweet and has no warning odour, so storage security and labelling matter.
What is the difference between MEG and propylene glycol?
MEG is cheaper and a better heat transfer fluid; propylene glycol is far less toxic and is the choice wherever there is food, pharmaceutical or human contact. They are not interchangeable in polyester chemistry.
How should MEG be stored?
In clean, dry, preferably stainless steel tanks with a desiccant breather or nitrogen blanket, since MEG is strongly hygroscopic. Carbon steel causes iron pick-up that discolours polyester.
Why does iron content matter?
Because even sub-ppm iron causes colour in polyester that cannot be corrected downstream. It is the most common reason for a polyester colour complaint, and it usually comes from the buyer's own carbon steel tankage.
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 repeat bulk cargoes on contract supply.
What concentration of MEG is used in coolant?
Typically 33 to 50% in water. A 50% solution protects to about −37 °C and also raises the boiling point, which is why it is the common automotive standard.
What is the typical shelf life?
Around 24 months in sealed storage. Because MEG is hygroscopic, water content and colour are the practical checks on stored material.
Ready to source Mono Ethylene 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.