Sequential impregnation vs. sol-gel synthesized Ni/Al2O3-CeO2 nanocatalyst for dry reforming of methane: Effect of synthesis method and support promotion

Abstract

The effects of CeO2 addition (10wt.%) as a support promoter on the catalytic performances of Ni catalysts supported over Al2O3 were studied in the dry reforming of methane (DRM). Ni/Al2O3-CeO2 nanocatalyst was prepared with sequential impregnation and sol-gel methods using low cost metal nitrate precursors to explore the effect of preparation method. The obtained materials were characterized by XRD, FESEM, BET and FTIR techniques. Catalytic activity and time-on-stream catalytic performance have been explored at different feed ratios, gas hourly space velocities and reaction temperatures. The results showed that CeO2 addition as a support modifier to the Ni/Al2O3 catalysts improved catalytic activity and stability. High dispersion of active phase in sol-gel synthesized catalyst was achieved in comparison with the impregnation synthesized one. FESEM images display smaller particle size (100% below 100nm) and a narrow particle size distribution for sol-gel synthesized sample, also this sample showed higher activity in the reforming reactions.