METHOD OF CONTROLLING PROCESS FOR PREPARING CAPROLACTAM Russian patent published in 1995 - IPC

FIELD: preparation of caprolactam. SUBSTANCE: in the course of oxime rearrangement the acidity of the resulting reaction mixture is regulated by varying the amount of oleum fed into a reactor. The amount of reflux fed to the top of the column of the amount of steam to the column bottom is regulated with respect to the optical density of rectified cyclohexanone and with respect to temperature at the top of the rectification column. The amount of alkali to the first column in which an alcoholic fraction is removed from the crude cyclohexanone as well as the amount of reflux and the amount of steam to the column bottom are registered by the temperature pulse at the top of this column. The flow rate of the product emerging from the column for obtaining rectified cyclohexanone is adjusted with respect to the temperature at the top of the column for recovering crude cyclohexanone to be fed to this column. The flow rates of reflux and steam are also regulated. Besides, the temperature at the top the first column in which an alcoholic fraction is removed from crude cyclohexanone (according to which temperature the amount of alkali, reflux and steam to the first column is regulated) is determined by the temperature at the top of the column in which crude cyclohexanone is recovered. EFFECT: more efficient preparation process. 1 dwg