The absorption plants are used in the gaseous stream for the solvent recovery or pollutans removal:

• Solvent recovery.
  DMF, DMAc and NMP are highly water soluble; TMIP exploits this characteristic by washing the exhaust air with water. The solvents is collected on the bottom of the tower in solution with water. The solution can be distilled to recover pure solvent.
• Pollutans removal.
  Compounds as H2S, SOx, mercaptani, NH3, HCl, Formaldehyde can be removed from polluted air/gaseous stream by chemical absorption in a scrubber with acid and basic aqueous solutions. The bottom solutions can be fed to additional oxidations/reduction treatments.