Carbon DIoxide, CO2, or Super-Gas?

Arc3 Gases is a trusted supplier of carbon dioxide to and surrounding areas.

The majority of people not affiliated with the industrial gas industry know carbon dioxide, CO2, as the bubbles in certain beverages and as the chemical in fire extinguishers. But CO2 is utilized in so many different forms that it is actually one of the most versatile gases available

Brief History

In the early 1600’s, Jan Baptista von Helmont, a Finnish scientist, discovered CO2 as the gas that resulted from burning wood. In the mid 1700’s an English chemist named Joseph Priestly, found that mixing water and CO2 being expended from a fermentation process created sparkling water which changed the taste of water and initiated the start of the soft drink industry.

One of the attributes of the gas that was discovered was it’s simple liquefaction process. This led to CO2 being the first commercial industrial gas to be offered as a packaged gas. As more knowledge about CO2 was discovered the only gas sold and used in all three of its phases – gas, liquid and solid.


For those involved in the gas industry, CO2 is most commonly associated with welding as a shielding gas and as a refrigerant in the food industry. CO2 also has other attributes that contribute to its uniqueness .

The most fitting example is when after making contact with water, CO2 forms carbonic acid. Although it is a weak acid, it is an acid nonetheless and can be used to modify the pH in some cases where the pH is an imperative system parameter. This is prominent in different industries such as paper production, textiles, and water treatment processes. An additional benefit is that carbonic acid is not stored as an acid (such as sulfuric or hydrochloric acids). As mentioned, the CO2 needs water to form the acid so it remains CO2 until needed and unlike many other acids, is not considered harmful.


CO2 is stored as a liquid regardless of the container. The pressure in an uninsulated CO2 cylinder is approximately around 800 psig depending on the ambient temperature. The result is that any application using liquid CO2 should be under pressure. Employees in the oil industry are aware can compensate for water in enhanced oil recovery (EOR) where the liquid is put in a blend with sand or sand like substance (proppant) and sent down an oil well to recover oil that is trapped inside the rock layers. EOR is a wide-ranging term that can refer to several different processes but the most frequent is fracking. In this case the proppant is forced into the oil rich rock through man made fissures. This leads to the fracture of the rock and the subsequent release of the oil inside of it. When CO2 is used instead of water, its natural expansion of volume from liquid to gas makes the fissure larger and helps recover additional oil.

It’s not common knowledge that liquid CO2 is also used to dry clean clothing. In a special high pressure washer, liquid CO2 is introduced with a stain remover. The laundry is treated as in a regular washing machine applying turbulence to clean the wash. When the cycle is finished, the dirt, grime and stain remover are separated from the liquid CO2. The liquid CO2 is then extracted to be used again and when the clothing is taken out and is clean and not wet since there was no water applied.

Every chemical (element or compound) has a state in which the three phases (gas, liquid and solid) have the same properties and is attained adjusting the pressure and temperature; this is referred to as the supercritical state. The supercritical state of CO2 can be generated in a uniquely designed processor. The fluid phase of supercritical CO2 is an exceptional solvent and is used to extract fragrances and color from flowers and plants. This method calls for unique tools and equipment and is executed under high pressure.


Solid CO2 or dry ice is used as a coolant in several ways and forms. When liquid CO2 is transported through a high pressure line and released using special nozzles, it right away turns to CO2 snow and is applied in food refrigeration and freezing. Dry ice pellets act as a replacement for regular ice in tubs that hold perishables for long road transportation.

Very small cuts of dry ice are (about the size of a grain of rice) utilized as an abrasive to rid surfaces of coatings without harming the surface itself by shooting the rice size pellets through a blasting lance. This is prominent in the aircraft industry where an airplane’s body has to maintain its integrity and cannot tolerate any damage that would occur with sand blasting. This is also advantageous because is that there is no need to separate the removed coating from the abrasive as the pellets sublimate to CO2 gas leading to a cleanup that is quite easy.

Calling CO2 a super-gas may be controversial, but it is certainly the most versatile product available in the industrial gas market.

To find out more about how you can get carbon dioxide in for any of your specialty gas operations, call Arc3 Gases at (910) 892-4016 or at

John Segura, PE

About the Author

John Segura is a licensed Professional Engineer and a well-rounded executive in the industrial gas business. He has been in the industry for over 30 years and is experienced in marketing, sales, and operations at both domestic and international levels. Segura has led teams of engineers and technicians as an R & D manager for major gas companies. His work lead him to running the marketing efforts of technology worldwide industrial gas suppliers. Now, he acts as an industry consultant on the business specializing in operations, applications and marketing.