OMEGA process

The OMEGA process (only mono ethylene glycol advanced process) is a process of the Royal Dutch Shell to produce Mono-ethylenlglycol from ethylene oxide, carbon dioxide as catalyst and water with high selectivity.

Process

The traditional process of monoethylene glycol (MEG) production is by reaction of ethylene oxide with water. The product of the first reaction stage, MEG, reacts with ethylene oxide on to diethylene glycol and triethylene glycol, which makes a distillation work-up necessary. The selectivity to MEG is about 90%.

In the OMEGA process, the ethylene oxide is first converted with carbon dioxide (CO₂) to ethylene carbonate to then react with water in a second step to selectively produce monoethylene glycol. The carbon dioxide is released in this step again and can be fed back into the process circuit. The carbon dioxide comes in part from the ethylene oxide production, where a part of the ethylene is completely oxidized.

(1) ${C_2H_4O + CO_2 \longrightarrow C_3H_4O_3}$

Ethylene oxide reacts with carbon dioxide to ethylene carbonate.

(2) ${C_3H_4O_3 + H_2O \longrightarrow HO{-}C_2H_4{-}OH + CO_2}$

ethylene carbonate reacts with water to (mono) ethylene glycol and carbon dioxide .

The selectivity to MEG is approximately 99.5%.

MEG is mainly used for the production polyethylene terephthalate and is also used a corrosion inhibitor in refrigerants.

A large-scale plant with 750,000 tonnes annual capacity was put in operation in 2009. ^[1]

References

1. ^ shell starts up MEG plant in Singapore

External Links

• description of Shell OMEGA process