Method for preparing caprolactam through gas phase rearrangement and refining caprolactam

The invention relates to the field of caprolactam production, and provides a method for preparing and refining caprolactam through gas-phase rearrangement aiming at the problems that a catalyst is difficult to regenerate and the gas consumption of reaction heat removal is large in a caprolactam gas-phase rearrangement reaction. The production device comprises a cyclohexanone-oxime production device, a cyclohexanone-oxime evaporator, a caprolactam production device, catalyst separation equipment, a solvent recycling system and a caprolactam refining system which are sequentially connected in series. The caprolactam production device is simultaneously connected with the catalyst separation equipment and the catalyst regeneration system. The inert solvent produced by upstream cyclohexanone-oxime is used for replacing carrier gas to remove reaction heat of the caprolactam reactor, and energy consumption is reduced. Meanwhile, the inert solvent can be used as a crystallization solvent to enter a caprolactam refini