In situ DRIFTS study on the partial oxidation of ethylene over Co-ZSM-5 catalyst

The interaction of C2H4 and C2H4 + O-2 with Co-ZSM-5 has been studied by in situ diffuse reflectance infrared fourier transform spectroscopy (DRIFTS). XRD, UV-vis and H-2-TPR were used for characterizing the Co-ZSM-5 samples. DRIFTS results showed that a partial oxidation of ethylene over Co-ZSM-5 occurred at definite temperatures( >= 250 degrees C) leading to the formation of formate species in the presence or absence of gas phase oxygen. Investigation on active sites in Co-ZSM-5 by using NO as probe molecules revealed that a reduction of Co3+ to Co2+ occurred during reaction and Co3+ (presenting in Co3O4) were primarily responsible for the oxidation of ethylene. (C) 2008 Elsevier B.V. All rights reserved.