PRODUCTION OF OXIME

PURPOSE:To obtain the corresponding oxime from an ketone or aldehyde and a hydroxylamine salt with no concomitant by-products, inorganic salts such as ammonium sulfate. CONSTITUTION:In producing the corresponding oxime (C) such as cyclohexanone oxime useful as an intermediate for caprolactam, a raw material for nylon, from a hydroxylamine salt (A) and a ketone or aldehyde, the aqueous solution 1a of the component A is partitioned by a cation exchange membrane 2 from the B-phase 1b to diffuse the component A through the membrane 2 to the B-phase where the component C is produced. By this method, the liberated acid as a by-product remains intact in the aqueous solution 1a; therefore, this acid can directly be recovered 5 and reused without the need for neutralization, resulting in no by-product salt formation. The component C, the objective oxime, thus produced in a free state can be separated 8 and recovered 9 without no concomitant by-product salt formation by neutralization, thus the liquor left can be put to circulatory use 4.