Gaseous carbon dioxide is used in carbonation of soft drinks, pH control in water treatment processes, chemical processing, food preservation, inert protection in chemical and food processing processes, welding gas, plant growth stimulator, in casting for hardening moulds and cores and for Pneumatic devices are also used in the diluent of sterilization gas (that is, the mixed gas of ethylene oxide and carbon dioxide is used as sterilization, insecticide, and fumigant, which is widely used in the sterilization of medical equipment, packaging materials, clothing, fur, bedding, etc. , bone meal disinfection, fumigation of warehouses, factories, cultural relics, books).
Liquid carbon dioxide is used as a refrigerant, low temperature testing of aircraft, missiles and electronic components, enhanced oil recovery, rubber polishing and control of chemical reactions, and can also be used as a fire extinguishing agent.