Separation Process Engineering, 5th Edition

Chapter 12

Absorption and Stripping

Thus far, we have talked almost exclusively about distillation. There are other unit operations that are very useful in processing chemicals and for pollution control. Absorption is a unit operation in which one or more components of a gas stream are removed by being taken up (absorbed) in a nonvolatile liquid (solvent). Liquid solvent must be added as a separating agent. Absorption is one method used to remove CO₂ from natural gas and flue gases so that CO₂ is not added to the atmosphere where it is probably one cause of climate change (Socolow, 2005).

Stripping is the opposite of absorption. In stripping, one or more components of a liquid stream are removed by being vaporized into an insoluble gas stream. ...