Wacker process
The Wacker process is an industrial process the chemical industry, in which by dehydration of acetic acid in the first step ketene is prepared further by addition of acetic acid to acetic anhydride reacts.
history
The process for the production of acetic anhydride via the preparation of ketene from acetic acid was developed by Wacker Chemie in 1922.
Procedure
The dehydration of acetic acid is carried out at temperatures of about 700 to 750 ° C under triethyl phosphate catalysis and reduced pressure:
The resulting mixture is cooled by adding ammonia , which neutralizes the phosphoric acid formed from the catalyst and the released water :
After purification, the resulting ketene reacts with acetic acid to form acetic anhydride at temperatures of 45 to 55 ° C and a pressure of 0.05 to 0.2 bar:
In industry, acetic anhydride is now largely produced using the Tennessee-Eastman acetic anhydride process .
Individual evidence
- ↑ Milestones in the history of the WACKER Group
- ^ A b Klaus Weissermel , Hans-Jürgen Arpe : Industrial Organic Chemistry. Wiley-VCH, 2003, ISBN 3-527-30578-5 , pp. 183-185.
- ↑ Zoeller, JR; Agreda, VH; Cook, SL; Lafferty, NL; Polichnowski, SW; Pond, DM Eastman Chemical Company Acetic Anhydride Process In: Catalysis Today 1992 , 13 , pp. 73-91. doi : 10.1016 / 0920-5861 (92) 80188-S