Abstract: | ![]() The liquid-phase oxidation of ethylamine with hydrogen peroxide was studied over tungsten-doped zeolites to develop a clean and simple route for producing acetaldehyde oxime. The investigations were firstly performed over W/MOR, where the coordinated state as well as the acidity of the W species were characterized. The reaction parameters, including H_2O_2 amount, solvent,temperature, tungsten content as well as catalyst amount, governed the activity and oxime selectivity. Under optimized reaction conditions, W/MOR showed an ethylamine conversion and corresponding oxime selectivity of 18.3% and 88.9%. W/MOR showed a superior performance in comparison to other tungsten-containing zeolites of W/Beta, W/MWW and W/Y. Although W/MOR exhibited lower amine conversion than titanosilicates of TS-1 and Ti-MWW, it gave higher selectivity to the main product of oxime. Moreover, W/MOR proved to be a robust catalyst, exhibiting a stable catalytic performance after being reused at least for 5 times. |