Abstract: The present invention provides a method for producing &egr;-caprolactam which comprises the step of treating, with water, a reaction product containing 1-aza-2-alkoxy-1-cycloheptene, which is obtained by gas phase Beckmann rearrangement reaction of cyclohexanone oxime using a solid catalyst in the presence of alcohol, to eliminate the 1-aza-2-alkoxy-1-cycloheptene. The resulting &egr;-caprolactam usually has a 1-aza-2-alkoxy-1-cycloheptene content of 100 ppm or less, preferably 25 ppm or less, more preferably 10 ppm or less and, therefore, has low free basicity and good qualities.

Abstract: A high purity &egr;-caprolactam is prepared by crystallizing an &egr;-caprolactam from a hydrocarbon solution containing a crude &egr;-caprolactam, and allowing the crystallized &egr;-caprolactam in contact with hydrogen in the presence of a hydrogenation catalyst. This process can effectively remove impurities from a crude &egr;-caprolactam, which is obtained by subjecting cyclohexanone oxime to the Beckmann rearrangement, and provide a high purity &egr;-caprolactam.

Abstract: There is disclosed a process for producing an aromatic amide compound of the general formula (4), including the steps of subjecting an o-nitrophenol compound of the general formula (1) to catalytic reduction in acetone or an aromatic hydrocarbon solvent under the presence of a nickel catalyst to give an o-aminophenol compound of the general formula (2); and (b) subjecting the o-aminophenol compound of the general formula (2) to condensation with an acid chloride compound having a sulfur content of 0.5% or less, based on the weight of the acid chloride compound, of the general formula (3) in acetone or an aromatic hydrocarbon solvent under an atmosphere of an inert gas having an oxygen concentration of 1% or less. The acid chloride compound having a sulfur content of 0.5% or less, based on the weight of the acid chloride compound, of the general formula (3) may be obtained by allowing a carboxylic acid compound of the general formula (5) to react with thionyl chloride and by concentrating the reaction mixture.