Pilot Plant Test on Beckmann Rearrangement Reaction of Cylohexanoneoxime

Abstract

Pilot plant test of continuous Beckmann rearrangement reaction of molten cyclohexanoneoxime by using oleum as catalyst was carried out. The equations derived from the variations of the reactions of the reaction's conditions show that more severe regulations are necessary on the contents of H2O in oxime and SO3 in oleum and on the flow rate ratio of feeds, when m, i. e. mole ratio of H2SO4 to oxime, decreases. Therefore the contents of impurities. H2O and (NH4) 2SO4, in molten oxime were measured under various conditions, and it was confirmed that if the melting conditions are held constant the quantity of said contents remain nearly constant without the effect of heating time. In the test range of m=2.5-1.5, the requirements to complete the reaction in one reactor are that strong agitation should be carried out in the reaction vessel and also that the average contacting time of the feeds should be over 40 minutes. When m decreases, the effect of m on quality and yield of lactam is not observed when the concentration of H2SO4, in organic matters and (NH4)2SO4 free basis, of reaction product is kept between 100-102%, and lactam to be polymerized is obtained with yield of 94-97%. By the measurements in this test, the apparent heat of rearrangement of oxime are 58.3-62.6kcal/oxime mole and over all heat transfer coefficients of reactor are 130-196kcal/m2hr°C.