The present invention relates to a
distillation method of
oxime.
Tower bottom materials are usually heated by still
distillation, a U-shaped outer tube or a rotary film
evaporator, long-term operation of the
tower bottom is easy to coking, and the
distillation efficiency is low. The invention is characterized in that: in the distillation and separation section of
oxime, at least one high
boiling point solvent is added in the distillation process, the content of the high
boiling point solvent in the
tower bottom is maintained in proportional to that of
oxime, and finally oxime is effectively separated by distillation.
Oxime is fed into a rectifying
tower, and is distilled at an absolute pressure of 0-0.4 MPa and at 20-300 DEG C to collect fractions. The unevaporated liquid left in the tower bottom is subjected to the processes of removing water and impurities, and is recycled to the rectifying tower as a high
boiling point solvent. The present invention can reduce total production costs, simplify operation processes, prevent the product from coking in the tower bottom or decomposing due to overheating,
ensure product distillation to be efficient, continuous, safe and stable, and improve product quality.