Recovery of HF from aqueous streams
 HF can be recovered from aqueous streams, particularly those which are dilute and have a concentration of HF lower than the azeotrope between HF and water. Such aqueous streams are contacted with carbon molecular sieves, preferably those having an average pore size of about 3.5 Angstroms, which adsorb both HF and water. When regenerated by heating, more dilute aqueous streams are desorbed at lower temperatures, followed by desorption of HF which is free of water, making possible a separation of HF and water and avoiding formation of the azeotrope. 
AlliedSignal Inc.
C B
C01B B01J
inventional inventional
Miguel A. Chin-Hsiung
Gualdron Chang