FIELD: chemical technology. SUBSTANCE: invention relates to a method of purification of adipic acid by crystallization or recrystallization in water which is one of the main substances used for synthesis of polyamide 6-6. Adipic acid comprises trace amount of a catalyst and minimal purity of adipic acid is at least 95%. The indicated crystallization or recrystallization is carried out in the presence of a strong protonic acid and/or in the presence of carbon monoxide. The preferable amount of a strong protonic acid is from 1 to 50 mole/1 mole of metal of a catalyst. Carbon monoxide is at least partial component of atmosphere where the solution is placed into the crystallization or recrystallization reactor or it makes the pressure into indicated reactor above atmosphere one. Said crystallization or recrystallization ensures to decrease the trace content of metallic catalysts in adipic acid. EFFECT: improved method of purification. 7 cl, 1 tbl
Title | Year | Author | Number |
---|---|---|---|
METHOD OF PURIFYING ADIPIC ACID BY RECRYSTALLIZATION | 1997 |
|
RU2178407C2 |
METHOD OF HYDROXYCARBONYLATION OF PENTENOIC ACIDS | 1997 |
|
RU2177936C2 |
CAPROLACTAM PRODUCTION PROCESS | 1997 |
|
RU2180332C2 |
TRANSITION METAL AND PHOSPHINE-BASED CATALYST PREPARATION METHOD | 1996 |
|
RU2167712C2 |
METHOD OF HYDROCYANIDATION OF ORGANIC COMPOUNDS WITH UNSATURATED ETHYLENE BOND | 1996 |
|
RU2186058C2 |
METHOD OF BUTADIENE OXYCARBONYLATION | 1996 |
|
RU2178406C2 |
METHOD FOR OXIDATION OF HYDROCARBONS | 1998 |
|
RU2210562C2 |
METHOD OF SEPARATION OF CATALYST BY ELECTRODIALYSIS THROUGH MEMBRANE | 1997 |
|
RU2181303C2 |
METHOD OF ELECTROCHEMICALLY PREPARING TRANSITION METAL AND PHOSPHINE-BASED CATALYST | 1996 |
|
RU2167716C2 |
METHOD OF LACTAM TREATMENT | 1997 |
|
RU2185374C2 |
Authors
Dates
2002-10-10—Published
1997-05-29—Filed