No abstract

No abstract

The present work highlights the influence of ceria over vanadia/alumina for the oxidative dehydrogenation of ethylbenzene to styrene with CO 2 as a soft oxidant. Various weight loadings (0, 3, 5, and 7 %) of ceria were incorporated into 10wt % V 2 O 5 /Al 2 O 3 catalyst by wet impregnation process. Structural and textural characterizations of the catalysts were performed by means of powder X-ray diffraction, temperature-programmed reduction, temperature-programmed desorption of CO 2 , N 2 adsorption-desorption analysis. Over 10 % V 2 O 5 /Al 2 O 3 , ethylbenzene conversion decreases from 62 to 49 % in a spam of 12 h. Ceria-incorporated catalyst (3 % CeO 2 /10 % V 2 O 5 /Al 2 O 3 ) showed steady ethylbenzene conversion of nearly 65 % with a styrene selectivity of 96 % for a period of 12 h time. Improved catalytic activity observed on this catalyst can be attributed to the increase in the number of redox/active VO x species after incorporation of ceria. The redox properties of 3 % CeO 2 /10 % V 2 O 5 /Al 2 O 3 and 10wt % V 2 O 5 /Al 2 O 3 were examined by reaction of CO 2 in pulses on to the partially reduced catalysts. The spent catalysts were characterized using XRD & TPR analysis to assess the reason for the deactivation of catalysts.

No abstract

No abstract