MONOETHYLENE GLYCOL (MEG)

Monoethylene Glycol (MEG) is a clear, colorless syrupy liquid. 
The primary hazard is the threat to the environment. 
Immediate steps should be taken to limit Monoethylene Glycol (MEG)'s spread to the environment. 

CAS:    107-21-1
MF:    C2H6O2
MW:    62.07
EINECS:    203-473-3

Since Monoethylene Glycol (MEG) is a liquid Ethylene glycol can easily penetrate the soil and contaminate groundwater and nearby streams.
Monoethylene Glycol (MEG) was first synthesized in 1859; however, Monoethylene Glycol (MEG) did not become a public health concern until after World War II. 
In fact, the first published series of deaths from Monoethylene Glycol (MEG) consumption involved 18 soldiers who drank antifreeze as a substitute for ethanol. 
Despite the early recognition that patients who drank ethanol in addition to Monoethylene Glycol (MEG) had prolonged survival when compared to those drinking ethylene glycol alone, antidotal treatment of Monoethylene Glycol (MEG) toxicity with ethanol was not evaluated until the 1960s. 
Today, Monoethylene Glycol (MEG) poisoning continues to be a public health problem, particularly in the southeastern United States. 
In 2009, US poison control centers received 5282 calls about possible Monoethylene Glycol (MEG) exposures, and the toxicology community believes these exposures are underreported.

Monoethylene Glycol (MEG) is the simplest aliphatic dihydric alcohol with chemical properties of alcohols such as being capable of generating ether, ester, or being oxidized into acid or aldehyde as well as being condensed to form ether or being substituted by halogen. 
Monoethylene Glycol (MEG)'s reaction with acyl chloride or acid anhydride generally forms di-esters. 
Under heating in the presence of catalyst (manganese dioxide, aluminum oxide, zinc oxide or sulfuric acid), Monoethylene Glycol (MEG) can be subject to intermolecular or intramolecular dehydration to form the cyclic ethylene acetals, which can react with nitric acid to generate glycol dinitrate (an explosive). 
Monoethylene Glycol (MEG) is the raw material for production of polyester resins, alkyd resins and polyester fiber. 
Monoethylene Glycol (MEG) can also be used as the refrigerant agent for automobile and aircraft engines refrigerant. 
In 1980, the glycol amount used as refrigerant agent is equal to the amount consumption for producing polyester. 

In addition, Monoethylene Glycol (MEG) can also be used for synthesizing polymers such as polyester fibers. 
Monoethylene Glycol (MEG), when used in combination with nitroglycerine can reduce the freezing point of explosives. 
Monoethylene Glycol (MEG) can also be used as the raw material of pharmaceuticals and plastics and high-boiling solvents. 
Industry applied ethylene as a raw material with first converting it to ethylene oxide and then hydrolyzing to produce Monoethylene Glycol (MEG).
Monoethylene Glycol (MEG) is of fire and explosion hazards. 

Monoethylene Glycol (MEG) is irritating to skin and mucous membrane with inhalation of vapors or skin absorption producing a narcotic effect on the central nervous as well as causing kidney damage. 
Rat, through oral administration, has a LD50 of 8540 mg/kg. 
The maximal allowable concentration in the workplace is 5 × 10-6.
Monoethylene Glycol (MEG) is a chemical substance that is produced by the reaction of ethylene or ethylene oxide. 
Monoethylene Glycol (MEG) is used as a corrosion inhibitor in antifreeze and in coolants, and in the manufacturing of polyester.
Monoethylene Glycol (MEG) is miscible in ethanol, acetone and water.
Monoethylene Glycol (MEG) is used as an inhibitor coating compound, which is a protective barrier in the form of a solid, film or fluid applied to a metallic surface to prevent corrosion. 
These barrier coatings possess chemical or physical properties that prevent corrosion reactivity and/or material degradation due to external factors.

Inhibitor coatings generate a passivation layer on the metal they protect, which prevents contact with water, chemicals and other corrosion causing materials. 
Passivation reduces the reactivity by electrochemical polarization.
Monoethylene Glycol (MEG) is an organic compound (a vicinal diol[7]) with the formula (CH2OH)2. Monoethylene Glycol (MEG) is mainly used for two purposes, as a raw material in the manufacture of polyester fibers and for antifreeze formulations. 
Monoethylene Glycol (MEG) is an odorless, colorless, flammable, viscous liquid. 
Monoethylene Glycol (MEG) has a sweet taste, but it is toxic in high concentrations.

Monoethylene Glycol (MEG) is an organic compound that is used in a variety of industrial applications. 
Its chemical formula is C2H6O2, and Monoethylene Glycol (MEG) is also referred to as ethylene glycol or 1,2-Ethanediol. 
Monoethylene Glycol (MEG) has an odorless, colorless appearance and is highly stable under normal environmental conditions. 
Monoethylene Glycol (MEG) has the ability to absorb moisture from the atmosphere and control humidity levels by forming hygroscopic solutions. 
Additionally, due to its low freezing point and viscosity index, Monoethylene Glycol (MEG) can be used as antifreeze for automotive cooling systems and domestic heating systems. 

Monoethylene Glycol (MEG) offers several advantages over other materials when used in industrial settings. 
For example, Monoethylene Glycol (MEG) provides a corrosion inhibitor for electrical contacts in insulated wire applications and prevents sediment buildup in automobile engines. 
Additionally, since Monoethylene Glycol (MEG) does not evaporate quickly at normal temperatures like some compounds do, it can act as a higher boiling point coolant or heat transfer agent in a system where ultra-high temperatures are present. 
Finally, due to its good thermal stability properties even at high temperatures, Monoethylene Glycol (MEG) can help to reduce carbon deposits within combustion chambers of engines.

Monoethylene Glycol (MEG) Chemical Properties
Melting point: -13 °C (lit.)
Boiling point: 195-198 °C
Density: 1.113 g/mL at 25 °C (lit.)
Vapor density: 2.1 (vs air)
Vapor pressure: 0.08 mm Hg ( 20 °C)
Refractive index: n20/D 1.431(lit.)
Fp: 230 °F
Storage temp.: 2-8°C
Solubility water: miscible
Form: Viscous Liquid
pka: 14.22(at 25℃)
Color: blue
Relative polarity: 0.79
PH: 6-7.5 (100g/l, H2O, 20℃)
Odor: Odorless
Explosive limit: 3.2%(V)
Water Solubility: miscible
Freezing Point: -11.5℃
Sensitive: Hygroscopic
λmax λ: 260 nm Amax: ≤0.03
λ: 280 nm Amax: ≤0.01
Merck: 14,3798
BRN: 505945
Exposure limits: Ceiling limit in air for vapor and mist 50 ppm (~125 mg/m3) (ACGIH); TWA 10 mg/m3 (particulates) (MSHA).
LogP: -1.36 at 25℃
CAS DataBase Reference: 107-21-1(CAS DataBase Reference)
NIST Chemistry Reference: Monoethylene Glycol (MEG) (107-21-1)
EPA Substance Registry System: Monoethylene Glycol (MEG) (107-21-1)

Monoethylene Glycol (MEG) is colorless transparent viscous liquid with sweet taste and moisture absorption capability. 
Monoethylene Glycol (MEG) is also miscible with water, low-grade aliphatic alcohols, glycerol, acetic acid, acetone, ketones, aldehydes, pyridine and similar coal tar bases. 
Monoethylene Glycol (MEG) is slightly soluble in ether but almost insoluble in benzene and its homologues, chlorinated hydrocarbons, petroleum ether and oils.
Monoethylene Glycol (MEG) ,CH20HCH20H, also known as glycol,ethylene alcohol, glycol alcohol, and dihydric alcohol, is a colorless liquid. 
Monoethylene Glycol (MEG) is soluble in water and in alcohol. 
Monoethylene Glycol (MEG) has a low freezing point,-25°C (-13 OF), and is widely used as an antifreeze in automobiles and in hydraulic fluids. 
Monoethylene Glycol (MEG) is used as a solvent for nitrocellulose and in the manufacture of acrylonitrile, dynamites, and resins.
Monoethylene Glycol (MEG) is a colorless, viscous, hydroscopic liquid with a sweetish taste. 
Often colored fluorescent yellow-green when used in automotive antifreeze. 
Monoethylene Glycol (MEG) is odorless and does not provide any warning of inhalation exposure to hazardous concentrations. 
The Odor Threshold in air is 25 ppm.

Uses    
Monoethylene Glycol (MEG) is mainly used as the antifreeze agent for preparation of the automobile cooling systems and the raw material for the production of polyethylene terephthalate (the raw material of polyester fibers and plastics material). 
Monoethylene Glycol (MEG) can also be used for the production of synthetic resins, solvents, lubricants, surfactants, emollients, moisturizers, explosives and so on. 
Monoethylene Glycol (MEG) can often used as alternative of glycerol and can often be used as hydration agent and solvent in the tanning industry and pharmaceutical industry. 
Monoethylene Glycol (MEG) has a strong dissolving capability but it is easily to be oxidized to toxic metabolic oxalic acid and therefore can’t be widely used as a solvent. 

The Monoethylene Glycol (MEG) can be supplemented to the hydraulic fluid and can be used for preventing the erosion of oil-based hydraulic fluid on the rubber of the system; the water-based hydraulic fluid with Monoethylene Glycol (MEG) as a main component is an inflammable hydraumatic fluid and can be applied to the molding machine in aircraft, automobiles and high-temperature operation. 
There are many important derivatives of Monoethylene Glycol (MEG). 
Low molecular weight polyethylene glycol (mono-uret ethylene glycol, bi-uret Monoethylene Glycol (MEG), tri-uret ethylene glycol or respectively called as diethylene glycol, triethylene glycol, tetraethylene glycol) is actually the byproduct during the hydration of ethylene oxide B for preparation of ethylene glycol.

Monoethylene Glycol (MEG) is used as an antifreeze inheating and cooling systems (e.g., automobileradiators and coolant for airplane motors).
Monoethylene Glycol (MEG) is also used in the hydraulic brake fluids;as a solvent for paints, plastics, and inks; as a softening agent for cellophane; and in themanufacture of plasticizers, elastomers, alkydresins, and synthetic fibers and waxes.
Reagent typically used in cyclocondensation reactions with aldehydes1 and ketones1,2 to form 1,3-dioxolanes.

Antifreeze in cooling and heating systems. 
In hydraulic brake fluids and de-icing solutions. 
Ingredient of electrolytic condensers (where Monoethylene Glycol (MEG) serves as solvent for boric acid and borates). 
Solvent in the paint and plastics industries. 
In the formulation of printers' inks, stamp pad inks, ball-point pen ink. 
Softening agent for cellophane. 
Stabilizer for soybean foam used to extinguish oil and gasoline fires. 
In the synthesis of safety explosives, glyoxal, unsatd ester type alkyd resins, plasticizers, elastomers, synthetic fibers (Terylene, Dacron), and synthetic waxes. 
To create artificial smoke and mist for theatrical uses.

The major use of Monoethylene Glycol (MEG) is as an antifreeze agent in the coolant in for example, automobiles and air-conditioning systems that either place the chiller or air handlers outside or must cool below the freezing temperature of water. 
In geothermal heating/cooling systems, Monoethylene Glycol (MEG) is the fluid that transports heat through the use of a geothermal heat pump. 
The Monoethylene Glycol (MEG) either gains energy from the source (lake, ocean, water well) or dissipates heat to the sink, depending on whether the system is being used for heating or cooling.

Pure Monoethylene Glycol (MEG) has a specific heat capacity about one half that of water. 
So, while providing freeze protection and an increased boiling point, Monoethylene Glycol (MEG) lowers the specific heat capacity of water mixtures relative to pure water. 
A 1:1 mix by mass has a specific heat capacity of about 3140 J/(kg·°C) (0.75 BTU/(lb·°F)), three quarters that of pure water, thus requiring increased flow rates in same-system comparisons with water.

The mixture of Monoethylene Glycol (MEG) with water provides additional benefits to coolant and antifreeze solutions, such as preventing corrosion and acid degradation, as well as inhibiting the growth of most microbes and fungi.
Mixtures of Monoethylene Glycol (MEG) and water are sometimes informally referred to in industry as glycol concentrates, compounds, mixtures, or solutions.

Production method    
1. Direct hydration of ethylene oxide is currently the only way for industrial-scale production of Monoethylene Glycol (MEG). 
Ethylene oxide and water, under pressure (2.23MPa) and 190-200 ℃ conditions, and can directly have liquid-phase hydration reaction in a tubular reactor to generate Monoethylene Glycol (MEG) while being with byproducts diethylene glycol, tripropylene ethylene glycol and multi-uret poly ethylene glycol. 
The dilute Monoethylene Glycol (MEG) solution obtained from the reaction further undergoes thin film evaporator condensation, and then dehydration, refinement to obtain qualified products and by-products. 

2. Sulfuric acid catalyzed hydration of ethylene oxide; ethylene oxide can react with water, in the presence of sulfuric acid as the catalyst, at 60-80 ℃ and pressure of 9.806-19.61kPa for hydration to generate Monoethylene Glycol (MEG). 
The reaction mixture can be neutralized by liquid alkaline and evaporated of the water to obtain 80% Monoethylene Glycol (MEG), and then distilled and concentrated in distillation column to obtain over 98% of the finished product. 
This method is developed in early time. 
Owing to the presence of corrosion, pollution and product quality problems, together with complex refining process, countries have gradually discontinued and instead change to direct hydration. 

3. Direct ethylene hydration; directly synthesize Monoethylene Glycol (MEG) from ethylene instead of being via ethylene oxide. 

4. Dichloroethane hydrolysis. 

5. Formaldehyde method.
Industrial preparation of Monoethylene Glycol (MEG) adopts chlorine ethanol method, ethylene oxide hydration and direct ethylene hydration with various methods having their characteristics, as described below.

6.Chlorohydrin method
Take chloroethanol as raw materials for hydrolysis in alkaline medium to obtain it. 
The reaction is carried out at 100 ℃. 
First generate ethylene oxide. 
Then pressurize at 1.01 MPa pressure to obtain ethylene glycol.

7.Ethylene oxide hydration
Hydration of ethylene oxide contains catalytic hydration and direct hydration. 
The hydration process can be carried out under either normal pressure or under compression. 
Normal pressure method generally take a small amount of inorganic acid as catalyst for reaction at 50~70 ℃.
Pressurized hydration had a high demand for the molar ratio of ethylene oxide over water which is higher than 1:6, to reduce the side reaction of producing the ether with the reaction temperature being at 150 °C and the pressure being 147kPa with hydration generating ethylene glycol.
There are currently gas phase catalytic hydration with silver oxide being the catalyst and the alumina oxide being the carrier for reaction at 150~240 ℃ to generate ethylene glycol.

8.Direct hydration of ethylene
Monoethylene Glycol (MEG), in the presence of catalyst (e.g., antimony oxide TeO2 with palladium catalyst) can be oxidized in acetic acid solution to generate monoacetate ester or diacetate ester with further hydrolysis obtaining the ethylene glycol.
The above several methods takes ethylene oxide hydration as good with simple process and is suitable for industrialization.

Poisoning and first aid    
This product is of low toxicity. 
Rat LD50: 5.5ml/kg~8.54ml/kg. People who is subject to oral administration by once has a LD50 of 80g~100g. 
The plasma concentration of ethylene glycol is 2.4g/L and can cause acute renal failure. 
Monoethylene Glycol (MEG) can be absorbed through the digestive tract, respiratory tract and skin. 
Monoethylene Glycol (MEG) can be discharged from the kidney in the form of prototype or ethanedioic acid (oxalate) from through oxidation. 
Monoethylene Glycol (MEG), after being oxidized into carbon dioxide, can be discharged from the respiratory tract.
Although Monoethylene Glycol (MEG) has a high toxicity but its volatility is small. 
Therefore, Monoethylene Glycol (MEG) is unlikely that the inhalation of it during production can cause severe poisoning.

Inhalation poisoning is manifested as blurred consciousness, nystagmus and urine containing protein, calcium oxalate crystals and red blood cells. 
Oral toxicity in clinical practice can be divided into three stages: the first stage is mainly the central nervous system symptoms, such as the performance of ethanol poisoning; the second phase of the main symptoms mainly include shortness of breath, cyanosis, and various manifestations of pulmonary edema or bronchopneumonia; at the third stage, there may be significant renal disease, low back pain, kidney area percussion pain, renal dysfunction, proteinuria, hematuria, urine containing calcium oxalate crystals, as well as oliguria, anuria and even acute renal failure.

Patients mistakenly take Monoethylene Glycol (MEG) should be subject to the treatment based on the general principles of first aid for oral poisoning and can be given 600 mL of 1/6 mol of sodium lactate solution and 10 mL of 10% calcium gluconate through intravenous infusion. 
Patients of severe poisoning can subject to treatment of artificial kidney dialysis.
Container of Monoethylene Glycol (MEG) should have "toxic agents" mark. 
Monoethylene Glycol (MEG), upon heating, should be sealed, vented to prevent inhalation of the vapor or aerosol. 
Avoid long-term direct skin contact with the product.

Reactivity Profile    
Mixing Monoethylene Glycol (MEG) in equal molar portions with any of the following substances in a closed container caused the temperature and pressure to increase: chlorosulfonic acid, oleum, sulfuric acid.

Health Hazard    
The acute inhalation toxicity of 1,2-ethanediolis low. 
Monoethylene Glycol (MEG) is due to its low vaporpressure, 0.06 torr at 20°C (68°F). 
Monoethylene Glycol (MEG)'s saturationconcentration in air at 20°C (68°F)is 79 ppm and at 25°C (77°F) is 131 ppm(ACGIH 1986). 
Both concentrations exceedthe ACGIH ceiling limit in air, which is50 ppm. 
In humans, exposure to its mist orvapor may cause lacrimation, irritation ofthroat, and upper respiratory tract, headache,and a burning cough. 
These symptoms maybe manifested from chronic exposure toabout 100 ppm for 8 hours per day for severalweeks.
The acute oral toxicity of 1,2-ethanediol islow to moderate. 
The poisoning effect, however,is much more severe from ingestionthan from inhalation. 
Accidental ingestion of80–120 mL of this sweet-tasting liquid canbe fatal to humans. 

The toxic symptoms inhumans may be excitement or stimulation,followed by depression of the central nervoussystem, nausea, vomiting, and drowsiness,which may, in the case of severe poisoning,progress to coma, respiratory failure, anddeath. 
When rats were administered sublethaldoses over a long period, there was depositionof calcium oxalate in tubules, causinguremic poisoning.
LD50 value, oral (rats): 4700 mg/kg
Ingestion of 1,2-ethanediol produced reproductiveeffects in animals, causing fetotoxicity, postimplantation mortality, andspecific developmental abnormalities. 
Mutagenictests proved negative. 
Monoethylene Glycol (MEG) tested negativeto the histidine reversion–Ames test.

Biochem/physiol Actions    
Monoethylene Glycol (MEG) is a low toxicity molecule and is used for embryo cryopreservation in many domestic animals.
Monoethylene Glycol (MEG) is an additive screening solution of Additive Screening Kit. 
Additive Screen kit is designed to allow rapid and convenient evaluation of additives and their ability to influence the crystallization of the sample. 
The Additive Kit provides a tool for refining crystallization conditions.

Synonyms
ETHYLENE GLYCOL
Ethane-1,2-diol
1,2-ethanediol
107-21-1
glycol
monoethylene glycol
1,2-Dihydroxyethane
2-hydroxyethanol
Glycol alcohol
Ethylene alcohol
Macrogol
Fridex
Tescol
Ethylene dihydrate
Norkool
Macrogol 400 BPC
Dowtherm SR 1
ethanediol
Zerex
Ucar 17
Lutrol-9
ethyleneglycol
Aethylenglykol
Ethylenglycol
1,2-Ethandiol
1,2-ethylene glycol
ethylen glycol
ethylene-glycol
146AR
Lutrol 9
MFCD00002885
NSC 93876
DTXSID8020597
PEG
1,2-dihydroxy ethane
HOCH2CH2OH
PEG 1000
M.e.g.
FC72KVT52F
CHEBI:30742
1, 2-Ethanediol
NSC-93876
ETHYLENE GLYCOL (1,2-13C2)
Glycol, ethylene-
DTXCID40597
Caswell No. 441
Aethylenglykol [German]
CAS-107-21-1
CCRIS 3744
Dowtherm 4000
HSDB 5012
NCI-C00920
PEG 3350
EINECS 203-473-3
UNII-FC72KVT52F
EPA Pesticide Chemical Code 042203
WLN: Q2Q
ethyleneglycole
Athylenglykol
ehtylene glycol
etylene glycol
AI3-03050
2-ethanediol
Ilexan E
4-vinyl cathecol
MEG 100
Solbanon (TN)
1,2-ethane diol
1,2-ethane-diol
ethane-1.2-diol
GXT
PEG 4000
1,2-ethyleneglycol
ethan-1,2-diol
mono-ethylene glycol
Macrogol 400
1,2-ethylene-glycol
Lutrol E (TN)
NANOSILVER+EG
YLENE GLYCOL
DuPont Zonyl FSO Fluorinated Surfactants
Ethylene glycol-[d6]
GLYCOL [INCI]
Macrogol 400 (TN)
Ethyleneglycol, ReagentPlus
Macrogol 1500 (TN)
Macrogol 4000 (TN)
Macrogol 6000 (TN)
EC 203-473-3
LOWENOL T-163A
Macrogol ointment (JP17)
HO(CH2)2OH
NCIOpen2_001979
NCIOpen2_002019
NCIOpen2_002100
Macrogol 400 (JP17)
ETHYLENE GLYCOL [II]
ETHYLENE GLYCOL [MI]
MLS002454404
BIDD:ER0283
Macrogol 1500 (JP17)
Macrogol 4000 (JP17)
Macrogol 6000 (JP17)
ETHYLENE GLYCOL [HSDB]
CHEMBL457299
ETHYLENE GLYCOL [MART.]
Ethylene glycol, AR, >=99%
Ethylene glycol, LR, >=99%
Macrogol 20000 (JP17)
CHEBI:46793
ETHYLENE GLYCOL [USP-RS]
ETHYLENE GLYCOL [WHO-DD]
PEG1000
HMS2267F07
Ethylene glycol, p.a., 99.5%
1,2-ETHANEDIOL (GLYCOL)
AMY22336
NSC32853
NSC32854
NSC57859
NSC93876
PEG 3600
PEG-1000
STR01171
Ethylene glycol, analytical standard
Tox21_202038
Tox21_300637
Ethane-1,2-diol (Ethylene Glycol)
Ethylene glycol, anhydrous, 99.8%
NSC-32853
NSC-32854
NSC-57859
NSC152324
NSC152325
NSC155081
STL264188
AKOS000119039
NSC-152324
NSC-152325
NSC-155081
Ethylene glycol, Spectrophotometric grade
NCGC00091510-01
NCGC00091510-02
NCGC00091510-03
NCGC00254292-01
NCGC00259587-01
BP-13454
BP-31056
GLYCEROL IMPURITY B [EP IMPURITY]
SMR001262244
ETHYLENE GLYCOL HIGH PURITY GRD 1L
Ethylene glycol, ReagentPlus(R), >=99%
DuPont Zonyl FSE Fluorinated Surfactants
Residual Solvent Class 2 - Ethylene Glycol
E0105
Ethylene glycol 1000 microg/mL in Methanol
Ethylene glycol, puriss., >=99.5% (GC)
FT-0626292
FT-0692978
1,2-Ethane-1,1,2,2-d4-diol-d2(9ci)
EN300-19312
Ethylene glycol, BioUltra, >=99.5% (GC)
Ethylene glycol, SAJ first grade, >=99.0%
C01380
D03370
D06418
D06419
D06420
D06421
D06422
D06423
Ethylene glycol, JIS special grade, >=99.5%
Ethylene glycol, anhydrous, ZerO2(TM), 99.8%
Ethylene glycol, Vetec(TM) reagent grade, 98%
A851234
Ethylene glycol, spectrophotometric grade, >=99%
Q194207
J-001731
F0001-0142
004143F9-240E-472F-9D5A-B1B13BBA2A18
Ethylene glycol, United States Pharmacopeia (USP) Reference Standard
Ethylene glycol, Pharmaceutical Secondary Standard; Certified Reference Material
ethylene glycol;1,2-ethanediol;ethane-1,2-diol;glycolethylene glycol;ethanediol;ethylene glycol 1,2-ethanediol ethane-1,2-diol glycolethylene glycol ethanediol
Residual Solvent Class 2 - Ethylene Glycol, United States Pharmacopeia (USP) Reference Standard