Patent number: 6046364
Abstract: A process for recovering a 1,1,1,5,5,5-hexafluoro-2,4-pentanedione ligand from a metal-ligand complex byproduct such as Cu.sup.+2 (1,1,1,5,5,5-hexafluoro-2,4-pentanedionate.sup.-1).sub.2, comprising: providing a copper-ligand complex byproduct of Cu.sup.+2 (1,1,1,5,5,5-hexafluoro-2,4-pentanedionate.sup.-1).sub.2 in a process stream; cooling and condensing the copper-ligand complex byproduct of Cu.sup.+2 (1,1,1,5,5,5-hexafluoro-2,4-pentanedionate.sup.-1).sub.2 to separate it from the process stream; contacting the copper-ligand complex byproduct of Cu.sup.+2 (1,1,1,5,5,5-hexafluoro-2,4-pentanedionate.sup.-1).sub.2 with a protonation agent, such as: sulfuric acid, hydrochloric acid, hydroiodic acid, hydrobromic acid, trifluoroacetic acid, trifluoromethanesulfonic acid, acid ion exchange resin, hydrogen sulfide, water vapor and mixtures thereof; and recovering 1,1,1,5,5,5-hexafluoro-2,4-pentanedione.
Type:
Grant
Filed:
December 7, 1998
Date of Patent:
April 4, 2000
Assignee:
Air Products and Chemicals, Inc.
Inventors:
John Anthony Thomas Norman, John Cameron Gordon, Yoshihide Senzaki