Preparation method of caprolactam and N-substituted caprolactam

The invention provides a preparation method of caprolactam and N-substituted caprolactam, comprising the following steps: adding a catalyst, namely filling a fixing bed with 150.0-200.0g of granular SO4/MxOy type solid superacid catalyst with phi=4.0-6.0 heating, namely heating to raise the temperature to 180.0-320.0 DEG C; and introducing nitrogen, namely introducing nitrogen to the fixing bed at the air speed of 50.0-70.0cm /min, so as to enable the catalyst to be in a state of being protected by nitrogen all the time. According to the preparation method, 6-caprolactone and ammonia (amine) are taken as raw materials, the raw materials are gasified at normal pressure and under nitrogen protection and then react by the fixing bed filled with the solid superacid catalyst, the productundergoes condensation and collection and is treated by a dehydration desolvent to obtain high-purity caprolactam and N-substituted caprolactam, the yield reaches 95% or above, the catalysis process is simple, the product yield