Combustion vs. Impregnation Synthesis of Cr/ZrO2 Nanocatalyst Used in Oxidative Dehydrogenation of Ethane to Ethylene by Carbon Dioxide

The Cr2O3-ZrO2 nanocatalyst was prepared via combustion and co-impregnation methods and characterizedby XRD, FESEM, EDX and BET techniques. The present research deals with nano-sized catalyst development for theoxidative dehydrogenation of ethane in the presence of CO2 with the aim of obtaining higher ethylene yield. The XRDresults confirm existence of ZrO2 as crystalline phase in the catalyst structure. FESEM analysis confirmed thatimpregnation prepared sample is nano scale. Furthermore, it reveals small particle size, uniform morphology and narrowparticle size distribution. EDX dot-mapping indicated homogenous dispersion of elements, especially for the impregnatedone. Also, according to the BET analysis, the impregnated nanocatalyst represented the higher surface area. Based on theexcellent characterization, Cr-based nanocatalysts synthesized via impregnation exhibited the superior product yieldsthrough all of the investigated temperature. However, the ethylene yield considerably declined during the reaction time.During the 10 h stability test, ethylene yield of combustion made catalyst were remained at same level throughout the600 min of time on stream and the deactivation was not observed.

Keywords:

Impregnation , Combustion , Cr/ZrO2 , Dehydrogenation , Ethane , Ethylene