Carbon dioxide (CO₂) is a byproduct of the fermentation process used to produce ethanol from rice. During fermentation, yeast breaks down the sugars in rice, producing ethanol and carbon dioxide as byproducts. The CO₂ is typically captured and separated from the ethanol through distillation or other separation methods.
Captured carbon dioxide can be utilized in various industries:

• Food and beverage: Used to carbonate soft drinks and beer.
• Industrial applications: Employed in welding and the production of dry ice.