| The focus of this work was to develop novel Ni-based catalysts for use in the steam reforming of concentrated mixtures of biomass-derived oxygenated hydrocarbons for hydrogen production, correlate the performance of the developed catalysts with the physicochemical properties, and carry out a comprehensive kinetic and reactor modeling study of catalytic reforming of concentrated crude ethanol (CRCCE) and a reactor modeling study of carbon dioxide reforming of methane (CDRM).;Catalyst development involved the design and synthesis of a series of 5 %wt. Ni catalysts supported on Ce0.4La0.6O2, La0.6Al0.4O2, LaO2, La0.6 Zr0.4O2, and Ce0.5Y0.5O 2 using the surfactant-assisted method in order to control the nickel particle size ensembles. A 15 %wt. Ni/Al2O3 (CP15) was also prepared by the co-precipitation method for comparison with previous catalysts for efficiency of steam reforming of oxygenated hydrocarbons. All catalysts were characterized using temperature-programmed reduction (TPR), BET surface area measurements, and pore volume and pore size distribution analysis. The BET surface area measurement indicated that the CP15 had the highest surface area. Catalyst performance evaluation studies conducted in a micro reactor at 873 K and liquid flow rate of 0.2 ml/min revealed that the 5 %wt. Ni/Ce0.4La0.6O2, 5 %wt. Ni/La 0.6Zr0.4O2 and the 5 %wt. Ni/LaO2 were the most stable in terms of conversion % (85.0, 87.6, 81.3) and hydrogen selectivity % (96.9, 84.1, 95.8), respectively, while the hydrogen selectivity on the Ni/Al2O3 was the least stable. The 5 %wt. Ni/Ce 0.4La0.6O2 had the highest and most stable hydrogen selectivity (96.9%), possibly because its high reducibility allowed a large fraction of the loaded nickel to be reduced at the reduction temperature used in the studies. The lanthana and ceria-containing catalysts were stable due to coke scavenging action and mobile lattice oxygen of the lanthanum oxide and ceria, respectively.;Mechanistic kinetic models developed were used for the simulation of CRCCE and CRDM using a pseudo-homogenous material and energy balance equations for a packed bed reactor. The model predicted the experimental results with AAD% of 4.28 and 4.6 for the CRCCE and CDRM, respectively. Also, the results revealed that the axial dispersion term still contributed to the results and should not be neglected. |
