What gas is used to make Dry Ice?
Dry ice is made from CO₂ (carbon dioxide), the same gas used to carbonate most soft drinks.
The difference lies in the type of cylinder used to contain it. The CO₂ used to produce dry ice (-78.5 °C) or for chilling cocktail glasses is extracted from high-pressure cylinders (200 bar) equipped with a dip tube. This tube runs vertically from the valve down to the bottom of the cylinder and allows the liquid phase of the compressed gas to be released freely.
The gas at the top pushes the liquid CO₂ at the bottom up through the tube and out of the valve. As the pressure is suddenly released, the liquid CO₂ expands and condenses into a space or mold, forming carbonic snow that is compacted under pressure into a solid block or pellet.
So, if you want to make dry ice or chill glasses, you must rent CO₂ cylinders with a dip tube, not the standard CO₂ bottles used for beer or soft drinks.
