Partial dehydration of cyclohexanone oxime
AssigneeBASF SE
InventorsHugo Fuchs, Rudolph Gath, Kurt Kahr, Klaus Kartte
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Abstract
A process for the partial dehydration of cyclohexanone oxime by treatment with aqueous solutions of inorganic salts, wherein the crude cyclohexanone oxime is extracted, above its melting point, with a concentrated ammonium salt solution and/or hydroxylammonium salt solution in countercurrent in an extraction column and the salt solution is then separated from the partly dehydrated cyclohexanone oxime, reconcentrated by evaporation and recycled to the oxime dehydration process. The cyclohexanone oxime melt which has been dehydrated to water contents of about 4 to 6% by weight is treated with a heated inert gas above its melting point and the off-gas is washed to remove entrained cyclohexanone oxime.
Claims10
A process for the partial dehydration of cyclohexanone oxime by treatment with aqueous solutions of inorganic salts, wherein the crude cyclohexanone oxime is extracted, above its melting point, with a concentrated solution of an ammonium and/or hydroxylammonium salt of a mineral acid in countercurrent in an extraction column and the salt solution is then separated from the partly dehydrated cyclohexanone oxime, re-concentrated by evaporation and recycled to the oxime dehydration process, wherein the cyclohexanone oxime which has been dehydrated to water contents of about 4 to 6% by weight is treated with a heated inert gas above its melting point and the gas is washed to remove entrained cyclohexanone oxime.
Dependencies are inferred from the claim text.