Norman S Carlson, 50Milford, NJ

5620936, Apr 15, 1997

Dec 14, 1993

8/166495

Vinci M. Felix - Kenneth Square PA
Charles E. Mosheim - Zionsville PA
Norman A. Carlson - Hockessin DE

E. I. DuPont de Nemours and Company - Wilmington DE
Cabot Performance Material - Boyertown PA

B01J 2034
B01J 3560

502 27

A process is disclosed for converting a spent catalyst from conventional fluorination processes into a commercially useful tantalum or niobium salt such as K. sub. 2 TaF. sub. 7 or K. sub. 2 NbF. sub. 7. The process broadly relates to dissolving the spent catalyst in water or an aqueous hydrofluoric acid solution, separating and disposing the undissolved residue, extracting the aqueous solution with a suitable solvent such as methyl isobutyl ketone (MIBK), and obtaining useful tantalum products from the MIBK solution such as a tantalum salt.