Degasification is the removal of dissolved gases from liquids, especially water or aqueous solutions.
Gases are removed for various reasons. Chemists remove gases from solvents when the compounds they are working on are possibly air- or oxygen-sensitive, or when bubble formation at solid-liquid interfaces becomes a problem. The formation of gas bubbles when a liquid is frozen can also be undesirable, necessitating degassing.
One way to achieve degassification is by Pressure Reduction.
The solubility of gas obeys Henry's Law.
The amount of a dissolved gas in a liquid is proportional to its partial pressure. Therefore, placing a solution under reduced pressure makes the dissolved gas less soluble. This technique is often referred to as Vacuum Degasification.
Specialized vacuum chambers, called vacuum degassers, are used to degas materials through pressure reduction.