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1- INFORMATION ABOUT PRODUCTS AT A GLANCE
Mono Ethylene Glycol (MEG)
Ethylene Glycol also known as Mono Ethylene Glycol (MEG), the simplest diol, is the mainly derivative for ethylene oxide and is colorless and odorless liquid with sweet taste.
Di Ethylene Glycol (DEG) & Tri Ethylene Glycol (TEG):
DEG & TEG are colorless and hygroscopic solutions with high boiling point. Approximately 10%wt of these oligomers mainly DEG (9%wt) and TEG (1%wt) are formed during hydrolyses of ethylene oxide to ethylene glycol. Significant quantities of DEG & TEG can be produced directly by the reaction of ethylene oxide with mono ethylene glycol. DEG & TEG are consumed as a chemical intermediate in wide variety of end products.
2- MANUFACTURING PROCESS
Ethylene Oxide is produced commercially by the direct catalytic oxidation of ethylene with oxygen over silver based catalyst under 220-270oC by the following reaction:
Main Reaction
Side Reactions
In the ethylene glycol section, the liquid phase thermal hydration of ethylene oxide with excess water is desired reaction to produce predominantly mono ethylene glycol which undergoes side reactions yield approx. 10%wt of oligomers (DEG & TEG) as co-products. Purification of this mixture is requiring repeated fractional vacuum distillation to remove the water and to separate the MEG from the higher glycols.
For the final applications “fiber and antifreeze” a purity of 99.9% and 98% must be achieved, respectively.
Specification for Mono Ethylene Glycol (MEG) | Appearance | Colorless, transparent | | Purity | 99.8%wt, min | | Color (Pt-Co) | 5 max | | Diethylene Glycol | 0.05%wt, max | | Water | 0.05%wt, max | | Specific Gravity | 1.1151-1.1156, 20/20oC | | Boiling range at 0.1013 Mpa | | | 5% vol | 196oC, min | | 95% vol | 199oC, max | | Aldehyde (as formaldehyde) | 8 mg/Kg, max | | Acidity (as acetic acid) | 10 mg/Kg, max | | Iron (as Fe) | 0.1 mg/Kg, max | | Inorganic chloride ( as Cl) | 0.05 mg/Kg, max | | Ash | 50mg/Kg, max | | UV transmittance | | | 220 nm | 80%, min | | 275 nm | 95%, min | | 350 nm | 99%, min |
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Products and Applications 
