Ethylene glycol is produced from ethylene oxide, which is produced through a reaction between ethylene and oxygen over a silver catalyst. Ethylene oxide then reacts with water to form ethylene glycol. A newer process called Shell OMEGA uses carbon dioxide to convert ethylene oxide to ethylene carbonate in the first step, then reacts the ethylene carbonate with water to selectively produce monoethylene glycol. Ethylene glycol is used as a coolant, heat transfer agent, and precursor to polymers, but is moderately toxic if ingested, as it can be oxidized to toxic compounds that damage the nervous system, heart, and kidneys.

2. • Ethylene glycol is produced
from ethylene (ethene), via the
intermediate ethylene oxide.
• Ethylene oxide reacts with water to produce
ethylene glycol according to the chemical
equation:
C2H4O + H2O → HO–CH2CH2–OH

3. • Ethylene oxide production. Ethylene and oxygen are
fed to a multi-tubular reactor, forming EO. This
exothermic reaction, conducted in fixed beds in the
reactor tubes, occurs in the gaseous phase with the use
of a silver catalyst supported on alumina. Steam is
generated by the heat of reaction.
Ethylene oxide recovery. The reactor product stream is
fed to the EO absorber for lights removal by water
quenching. Part of this gaseous overhead stream is
recycled to the reactor, while the other part is sent to a
carbon-dioxide-removal unit composed of an absorber
and a stripper. In this unit, CO2 is separated to be used
in ethylene carbonate production.

5. • Shell OMEGA is the first process to enable ethylene
glycol production via a fully catalytic process.
According to the licenser, the process is able to achieve
EO-to-EG conversion and selectivity near 100%, leading
to production of MEG only.
• A higher selectivity is achieved by use of this process.
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 mono-ethylene 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.

6. USES
• Coolant and Heat transfer agent
• As an anti- freeze or anti- crystallizing agent
• Pre- cursors to polymers (polyester and
polyethylene terephthalate PET)
• Dehydrating agent.

7. ETHYLENE GLYCOL TOXICITY
•Ethylene glycol is moderately toxic,
with an oral LDLo = 786 mg/kg for
humans.
• The major danger is due to its sweet
taste, which can attract children and
animals.
•Upon ingestion, ethylene glycol is
oxidized to glycolic acid, which is, in
turn, oxidized to oxalic acid, which is
toxic.
•EG and its toxic by-products first
affect the central nervous system,
then the heart, and finally the
kidneys.
•Ingestion of sufficient amounts can
be fatal if untreated.