Purifying cyclohexanone oxime - from chloroide and nitrate by washing with aqs sulphate or phosphate solns

摘要

Cyclohexanone oxime (I) is freed from Cl- and/or NO3-, which interfere with the conversion of (I) to caprolactam in strong acids, by treating (I) in the melt or in presence of inert solvents with aq. solns. of sulphates and/or phosphates, in which (I) is only slightly sol. There must be an adequate difference in density between the org. and aq. phases. Losses of (I) are low. The aq. soln. can be re-used a number of times without treatment.