A cleaner ammoximation of cyclohexanone over Ti-MWW in dimethyl carbonate

Abstract In this paper, dimethyl carbonate was selected as the solvent for the cyclohexanone ammoximation over Ti-MWW. Under the optimized reaction conditions, high conversion of cyclohexanone (99.8%) and high selectivity to oxime (99.6%) were achieved. The results of reuse of the catalyst showed that the Ti-MWW in this reaction system had better stability. Though the deactivation of the catalyst occurred after being used five times, the selectivity to cyclohexanone oxime was still kept above 99.9%, and calcining could easily recover catalytic activity. This work may provide a more environmentally benign solution for the industry production of cyclohexanone oxime.