Degassing, also known as degasification, is the removal of dissolved gases from liquids, especially water or aqueous solutions.
Chemists remove gases from solvents when the compounds they are working on are possibly air- or oxygen-sensitive (air-free technique), or when bubble formation at solid-liquid interfaces becomes a problem.
In some cases, however, the solvent and the solute decompose, react with each other, or evaporate at high temperature, and the rate of removal is less reproducible.
The advantage of this method is that that ultrasonic degassing can be done in a continuous-flow mode, which makes it suitable for commercial-scale production.
To maximize this process called sparging, the solution is stirred vigorously and bubbled for a long time.
For example, especially in the field of electrochemistry, ammonium sulfite is frequently used as a reductant because it reacts with oxygen to form sulfate ions.
The latter method is particularly useful because a high concentration of ketyl radical generates a deep blue colour, indicating the solvent is fully degassed.
In this laboratory-scale technique, the fluid to be degassed is placed in a Schlenk flask and flash-frozen, usually with liquid nitrogen.
Unintended degassing can happen for various reasons, such as accidental release of methane ( CH4 ) from the seabed during human activity such as underwater exploration by the energy industry.
Natural processes such as tectonic plate movement can also contribute to methane release from the ocean floor.