POST TREATMENT OF CDON/CDOL MIXTURE BY A PAIR OF LATERAL TAKING OFF COLUMN

摘要

PROBLEM TO BE SOLVED: To provide a method of obtaining pure cyclododecanone (CDON) from a mixture containing a low boiling point component, CDON, a middle boiling point component (MB), cyclododecanol (CDOL) and a high boiling point component (HB).SOLUTION: A low boiling point component LB is separated by a distillation column 6 from a mixture O obtained by oxidation 1 of cyclododecanone (CDAN) and dehydrogenation 5 of the produced CDOL, a first mixture ABC1 containing CDON, MB, CDOL and HB obtained from a bottom of the column is supplied to a first lateral taking off column 7, a fraction A1 is removed from a top of the column, a column bottom liquid C1 containing CDOL and HB is removed, a second mixture ABC2 containing CDON, CDOL and MB is supplied from the lateral taking off part to a second lateral taking off column 8, a fraction A2 is removed from the top of column, a column bottom liquid C2 containing CDOL and HB is removed, a third mixture ABC3 is removed from the lateral taking off part, A1 and A2 is combined and object fraction A containing increased CDON is obtained.