Synthesis of catalysts for hydrogen production and determination of activity by steam reforming of ethanol

The aim of the study was to synthesis catalyst which is highly active ethanol steam reforming and highly stable in the presence of steam at elevated temperature conditions. In the scope of the present study, Ni/Al2O3, Co/Al2O3, Ni-Co/Al2O3, Co/ZnO and Ni/CeO2-ZrO2 catalysts were synthesized by the impregnation, co-impregnation and co-precipitation method using various loadings of the active metal. Catalysts were characterized by XRD, XRF, SEM, BET, TGA and FT-IR techniques. The catalytic activity for the ethanol steam reforming was investigated in different temperature (300-600°C), steam: carbon molar ratio (3:1-12:1) and LHSV (0.3-0.9 L/gcat.h) range. The complete ethanol conversion was achieved on all catalysts. Co/ZnO with 20 wt% metal loading showed the highest hydrogen yield (2.62 mol H2/mol ethanol) and high heating value (65.26 Mj/kg). Ni/CeO2-ZrO2 catalyst exhibited the highest hydrogen selectivity (85.46%). In the ethanol steam reforming, highest hydrogen yield (2.38 mol H2/mol ethanol), hydrogen selectivity (88.58%) and high heating value (55,93Mj/kg) were reached at 600°C with 0.05 L/gcat.h LHSV. The highest hydrogen yield and selectivity were obtained with 12: 1 S: C molar ratio, as the high heating value was obtained with 9: 1 S: C molar ratio. In the stability test performed with Ni/CeO2-ZrO2 catalysts, it observed that Ni/CeO2-ZrO2 represented the stability during 18 hours.