MEG (Monoethylene Glycol)
Description
Monoethylene Glycol (MEG) is a colorless, virtually odorless and slightly viscous liquid. It is miscible with water, alcohols, aldehydes and many organic compounds. MEG will not dissolve rubber, cellulose acetate or heavy vegetable and petroleum oils. MEG has a low volatility and it is 50% more hygroscopic than glycerol at room temperature.
Properties
| Unit | Quantity |
|---|
| Molecular weight | g/mol | 62.08 |
| Boiling point | °C | 197 |
| Freezing point | °C | -13 |
| Viscosity | at 20°C (cp) | 20 |
| Specific heat | at 0°C
(cal/gm/°C) | 0.543 |
Specifications
Drum shipment
| Unit | Quantity / description |
|---|
| Appearance | visual | clear |
| Specific gravity | at 20°C/20°C | 1.1153-1.1156 |
| Purity | wt % | 99.9 min |
| Water | wt % | 0.2 max |
| Acidity (as acetic acid) | wt % | 0.002 max |
| Color | APHA | 10 max |
| Iron (Fe) | ppm, wt | 0.5 max |
| Chloride | ppm, wt | 0.5 max |
| Ash | wt % | 0.5 max |
Fiber grade bulk shipment
| Unit | Quantity / Description |
|---|
| Appearance | visual | clear |
| Specific gravity | at 20°C/20°C | 1.1153-1.1156 |
| Distillation range | °C (at 760 mmHg) | 196 min
199 min |
| Purity | wt % | 99.9 min |
| Water | wt % | 0.05 max |
| DEG Content | wt % | 0.05 max |
| Acidity (as acetic acid) | wt % | 0.001 max |
| Color | APHA | 5 max |
Iron (Fe)
UN Transmittance:
Wave length % | ppm, wt | 0.10 max |
| 220 | nm | 70 min |
| 275 | nm | 90 min |
| 350 | nm | 98 min |
| Aldehyde (as acetaldehyde) | ppm, wt | 10 max |
| Chloride | ppm, wt | 0.5 max |
| Ash | wt % | 0.001 max |
| PH at 20°C, dimensionless | °C | 6.5-7.5 |
Hazards and safety
MEG is not considered to be a health hazard when handled under
normal industry conditions. It has a relatively low degree of acute
and chronic oral toxicity and the average fatal dose is 100 ml for
adults. It is only slightly irritating to the eyes and skin.
Applications
MEG is mainly used in the production of polyester, polyethylene terephthalate (PET) and antifreeze solutions. It is an important dehydrating agent, good humectant and an industrial solvent.
Storage and handling
MEG is stored and shipped in stainless steel tanks (or in ordinary steel drums/tanks with epoxy resin coating) to avoid iron contamination. Where contamination by iron is desirable, metal in contact with the glycol should be aluminum or stainless steel (type 304/316). If contamination by halides is undesirable, the packing of the valves and the gaskets should be made of asbestos or other halide-free materials. Also, an inert gas (nitrogen) blanketing should be maintained to avoid oxygen contact which is a main course of U.V. deterioration.
Packaging
MEG is loaded after thorough cleaning and drying of tanks and nitrogen purging to ensure that it remains chloride, iron, and ash-free. Shipments are made in tanks, tankers of varying capacities and in lined steel drums (220 liters). Precautionary labelling: “Ethylene Glycol. For Industrial Use Only. Harmful or Fatal if Swallowed”. UN or ID No. 1142.
Operating companies
Eastern Petrochemical Company (SHARQ).
Saudi Yanbu Petrochemical Company (YANPET).
Jubail United Petrochemical Company (UNITED).
رجوع