Synergetic effects of Sn and Ti incorporated in MWW zeolites on promoting the oxidative hydration of ethylene with H2O2 to ethylene glycol

Although the titanosilicate zeolite catalyzed one-pot oxidative hydration of ethylene with hydrogen peroxide (H 2 O 2 ) to ethylene glycol (EG) takes advantages of step-saving and facile operation, both H 2 O 2 utilization efficiency and EG yield are relatively low. In the present work, Sn-doped Ti-MWW zeolites, named Sn-Ti-MWW, were developed for this oxidative hydration, showing the much higher H 2 O 2 utilization efficiency and EG yield, compared to Ti-MWW. The extensive characterizations of Sn-Ti-MWW zeolites, in combination with Density Functional Theory (DFT) calculations, verify that the doping of Sn into Ti-MWW leads to the higher electropositivity of the Ti species, resulting in the stronger acidity of the zeolite, which is helpful to the H 2 O 2 utilization and EG production. In addition, although the catalyst deactivation is observed due to the deposition of the bulky byproducts onto the active sites and/or into the zeolite micropores, the simple calcination of the used catalyst readily restores its catalytic activity. Therefore, it is anticipated that the developed Sn-Ti-MWW catalyst might be applicable in the one-pot oxidative hydration of ethylene with H 2 O 2 to EG industrially.