What is Ethylene Oxide? 
Ethylene Oxide is a Volatile Organic Compound (VOC) with the chemical formula of C2H4O. Ethylene Oxide is colorless gas that has a slightly sweet odor; this odor is particularly noticeable when concentration in the air meets or exceeds 500ppm. This gas is highly flammable and carries a plethora of health risks. Ethylene oxide is water soluble and is highly reactive with many acidic and alkaline compounds. Because of this, Ethylene Oxide is commonly used in the creation of dozens of industrial and sterilization chemicals.
Where is Ethylene Oxide Found?
Though first identified in 1859 by a chemist in Germany, Ethylene Oxide made its commercial debut in 1914 when BASF opened a facility that used what is now considered an inefficient process to create the compound known as the chlorohydrin process. The process has since evolved to become safer, and more efficient making Ethylene Oxide the most commonly used industrial chemical on the planet.
Ethylene Oxide is used in hundreds of different applications across several industries. The most common use is as a building block for other chemicals. Some of the products created with Ethylene Oxide include polyester fabrics and upholstery, anti-freeze, industrial and household cleansers, fiberglass, resins, plastic packaging, and many more.
Derivatives of ethylene oxide are used in a number of different personal care products including cosmetics, shampoos, lotions, medicines, and ointments.
The application that ethylene oxide gets the most media and regulatory attention for is medical sterilization. The chemical is used in the sterilization of medical and pharmaceutical supplies that cannot sustain traditional high heat sterilization. These supplies generally include items with plastic components that could melt as well as electronic components that could be damaged by high heat. Since Ethylene Oxide must be used at a low temperature because of its risk of combustion, it is the best option to sterilize cloth bandages and medical ointments too. Ethylene oxide is the most commonly used non-heat related means of medical sterilization in the world with hundreds of facilities in the U.S. alone.
Why is Ethylene Oxide a Concern?
There has been a lot of talk about Ethylene Oxide and medical sterilization facilities in the news recently. This is because previous regulations on Ethylene Oxide were often lax and non-specific. However, all recent research indicates that Ethylene Oxide is dangerous and known carcinogen. The results of these studies have led to public outcry for stricter regulation in treatment and abatement making Ethylene Oxide one of the most focused on emissions in the world.
In the United States, OSHA now requires employers to monitor the amount of Ethylene Oxide their employees are exposed to daily. Employers must also provide protective gear because even low-level exposure to Ethylene Oxide can cause irritations to the eyes, respiratory system, and skin, as well as severe headaches and nausea. Long term exposure to low levels can lead to these symptoms becoming a chronic issue such as asthma. Direct contact with the skin can cause burns, and permanent scaring, and leads to higher physical exposure since the compound can enter the blood stream through a burn.
In December of 2016, the EPA classified Ethylene Oxide as a known carcinogen. This means that clinical studies were able to prove, without doubt, that Ethylene Oxide exposure was directly responsible for increased risk of white blood cell related cancers in people, such as non-Hodgkin lymphoma, myeloma, and lymphocytic leukemia. These studies also saw a direct link between Ethylene Oxide and breast cancer in women. The EPA states that “Based on available data, we do not expect ethylene oxide levels in the air around facilities to be high enough to cause immediate health effects.” However, they do encourage people who have spent their entire lives in communities that house these facilities that produce or use ethylene oxide to get regular check-ups, including cancer screening.
How do we treat Ethylene Oxide?
Historically, the most commonly used type of equipment used to treat Ethylene Oxide has been a Catalytic Oxidizer. A catalytic oxidizer is a type of pollution control equipment that is used to abate industrial exhaust streams laden with volatile organic compounds (VOCs) like Ethylene Oxide. Also known as a CO, CATOX, CTO (Catalytic Thermal Oxidizer), RCO (Regenerative Catalytic Oxidizer), or CRO (Catalytic Recuperative Oxidizer), a catalytic oxidizer works to destroy Ethylene Oxide by raising the temperature of the exhaust stream to a point in which the chemical bonds that hold the VOC molecules together are broken (oxidized) across the precious or base metals from the catalyst media. The Ethylene Oxide in the process exhaust stream is converted to carbon dioxide (CO2), water (H2O), and thermal energy. In a catalytic oxidizer, the operating temperature is substantially less than straight thermal oxidation, and when combined with a VOC loading level from the process stream, the system can become self-sustaining; often requiring minimal auxiliary fuel to support operation.
A catalyst is a substance that accelerates the rate of the chemical reaction of the volatile organic compound without being consumed. The process of catalytic oxidation which, in addition to reducing fuel consumption and operating at a relatively low temperature level, minimizes the formation of NOx. The reduction of the CO and minimization of NOx formation are very important as both of these compounds are regulated as strictly as VOCs by the Environmental Protection Agency (EPA).
One of the specific types of RCO units for treating Ethylene Oxide is an Electric Regenerative Catalytic Oxidizers (E-RCO). For many years, GCES has offered the use of this technology to our more forward-thinking customers for sterilized storage room exhaust streams. The method of abatement for this technology is the same as a traditional RCO, however the waste heat from these units can be recirculated between the room(s) from the E-RCO, without generating products of combustion… all while treating the Ethylene Oxide and saving energy. Depending on the location of each facility, the storage room may require heat during the winter months; this technology cuts that need and added cost.
Gulf Coast Environmental Systems has extensive experience handling Ethylene Oxide. We understand the need and importance of proper abatement, for public health, staff safety, and regulatory reasons, and have custom designed systems to meet those needs. If you have questions about treating Ethylene Oxide, or would like to speak to one of our pollution control experts about options, please contact us at sales@gcesystems.com, or at 832.476.9024.
Gulf Coast Environmental Systems VOC Series:
Part 1: BTEX is an acronym that stands for Benzene, Toluene, Ethylbenzene and Xylenes.
Part 2: Chlorine Abatement
Part 3: NOx is the family of air polluting chemical compounds, Nitrogen Oxides.
Part 4: Lead is also known (incorrectly) as mercury because they are often found together
Part 5: Industrial air scrubbers for the treatment of ammonia
Part 6: SOx, the compounds of sulfur and oxygen molecules including Sulfur Monoxide, Sulfur Dioxide and Sulfur Trioxide
Part 7: Hydrocarbons – Methane, Ethane, Propane, Butane, Pentane, Hexane
Part 8: Methyl Mercaptan – Methyl Mercaptan, also known as Methanethiol
Part 9: H2S – Highly corrosive Hydrogen Sulfide
Part 10: Dimethyl Sulfide – Methylthiomethane
Part 11: Sulfuric Acid – H2SO4
Part 12: Ethylene Oxide – EtO