Process for the separation of amides from nitriles
US4575434A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 28, 1984 |
| Grant date | Mar 11, 1986 |
| Priority date | — |
| Expiry date | Sep 28, 2004 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C253/34
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A process for the removal of impurities comprising amides from a solution comprising nitriles and the impurities. A reaction mixture is formed which includes the solution, a layered mineral comprising aluminum silicates having exchangeable alkaline or alkaline earth cations on the surfaces of the layers and an acid which has an acid strength sufficient to protonate the amides at amide protonation conditions, but in which the solubility of the salt of the acid and exchangeable cation at those conditions is such that the equilibrium of the protonation reaction is substantially in the direction of the amides remaining in a protonated form. The water content of the reaction mixture must be less than about 0.5 wt. % for substantially all of the reaction time. The reaction mixture is maintained for a sufficient time at the amide protonation conditions for protonation of the amides and exchange of the protonated amides and exchangeable cations to occur, the protonated amides adhering to the surfaces of the layers. Nitriles having a reduced content of impurities may then be separated from the reaction mixture. Effective means of separation are rotating drum vacuum filters, preferably two i…
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