Ethylene Oxide - EO

Ethylene Oxide

Ethylene oxide is a colorless, odorless gas.  It is very reactive and highly flammable. Ethylene Oxide is soluble in water.  

Applications

Ethylene oxide (EO) is a common biocide used in both the healthcare and food industries. It is widely employed for sterilization purposes.  Ethylene oxide in the air largely results from industrial manufacturing, particularly large scale cleaning or sterilizing processes. 

Health and Environmental Effects

Dangerous ethylene oxide exposure is an occupational hazard. The gas enters the body through inhalation or accidental ingestion of, or dermal contact with, ethylene oxide. Low levels of exposure over long periods of time can cause irritation of the eyes, skin, and respiratory passages. Exposure can also affect the nervous system. Headaches, memory loss, and numbness are common symptoms. Women are cautioned specifically because the increased risk of miscarriage. Ingestion of ethylene oxide can lead to nausea, vomiting, and diarrhea. Dermal contact with ethylene oxide can cause severe skin burns.

Ethylene oxide is toxic to all living things and exposure to high levels may cause significant harm, particularly to aquatic organisms. While it does not accumulate in the environment, it takes considerable time to breakdown naturally. As a volatile organic compound, it is thought to contribute to ground level of ozone, which damages crops and other organic materials.

Regulatory Considerations

Ethylene Oxide is considered a hazardous air pollutant (HAP) by the US EPA.  The US EPA regulates Ethylene Oxide emissions through its National Emission Standards for Hazardous Air Pollutants (NESHAP), focusing on commercial sterilization and fumigation operations that emit ethylene oxide.  New and existing major sources of ethylene oxide emissions must control emissions with the Maximum Achievable Control Technology (MACT).  

Control Technologies

A HEIL Series 730 countercurrent packed tower can be used to absorb the ethylene oxide emissions in aqueous solutions.  However normal liquid recirculation techniques are not adequate.  Ethylene oxide can be transformed into glycol when hydrolyzed, though that reaction occurs very slow. The catalyzing reaction of sulfuric acid can speed up the rate of hydrolysis and allow efficient chemical absorption to occur, resulting in high removal efficiencies of Ethylene Oxide.  Vessel design often requires the use of furan based resins for chemical resistance, which HEIL is highly experienced with.