Komateedi N. Rao

Nanocrystalline ceria–praseodymia and ceria–zirconia solid solutions for soot oxidation

The relative effects of Zr4+ and Pr3+/4+ dopants on the structure, redox properties, and catalytic performance of nanosized ceria was studied. The investigated ceria–zirconia and ceria–praseodymia (CP) solid solutions were prepared by a modified coprecipitation method, characterized by a variety of techniques, and evaluated for soot oxidation. The characterization results indicate that CP has more surface and bulk oxygen vacancies, redox sites, and lattice oxygen mobility, and better thermal stability. Besides having low specific surface area, CP is more active in soot oxidation. This better activity has been attributed to the presence of more surface and bulk oxygen vacancies, which promote the adsorption of gas-phase oxygen and the formation and mobility of large numbers of active oxygen species.

Hydrogenolysis of bioglycerol to 1,2-propanediol over Ru/CeO2 catalysts: influence of CeO2 characteristics on catalytic performance

Abstract Hydrogenolysis of glycerol to 1,2-propanediol is an alternative route for efficient utilization of biomass-derived glycerol to value-added chemicals. In this study, catalytic hydrogenolysis of glycerol was systematically investigated over various Ru/CeO2 catalysts. CeO2-support was prepared by different methods and Ru deposition by wet impregnation method. Synthesized catalysts were characterized by various techniques, namely, XRD, XPS, TPR, TPD, and other. Hydrothermally synthesized CeO2-supported Ru catalyst showed relatively more number of acid sites with mild acid strength and exhibited highest conversion and product selectivity. Effect of various parameters including Ru loading, reaction temperature, and hydrogen pressure was evaluated and addressed.