(691h) Hydrogen Production from Bio-Ethanol Steam Reforming Over Co-Based Catalysts

Bio-Ethanol Steam Reforming (BESR) has attracted much attention recently as an environmentally friendly route to produce hydrogen without contributing to the green house effect. Hydrogen is an important energy carrier with a high gravimetric energy density and is likely to be the fuel of choice for transportation and mobile applications when used with fuel cells. Due to low toxicity, ease of deliverability and the abundant supply of the raw materials, bio-ethanol obtained from the fermentation of biomass (e.g. sugar canes, cellulose) offers much potential for hydrogen production. Moreover, the development of non-precious metal catalyst systems with high activity, selectivity, and stability will make this route economically competitive.

In this study, we have examined the effects of active metal loading, promoters, supports, synthesis parameters, and preparation methods of Co-based catalysts for BESR. We have also investigated the complex network of reactions and active sites over cobalt-based catalyst during BESR through steady-state and transient reaction experiments and by using various characterization techniques, including Temperature Programmed Reaction (TPRxn), Temperature Programmed Reduction (TPR), Temperature Programmed Desorption (TPD), Temperature Programmed Oxidation (TPO), N2 Physisorption, Pulse Chemisorption, X-Ray Diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS), Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS), Laser Raman Spectroscopy (IRS), Thermogravimetric Analysis-Differential Scanning Calorimetry (TGA-DSC), Isotopic Labeling, Scanning Electron Microscopy (SEM), and Transmission Electron Microscopy (TEM). The relationship between sample properties and activity has been established and a BESR reaction mechanism has been proposed. H2 yields over 90% have been achieved at temperatures below 450°C. In addition, the deactivation mechanism has been examined and catalysts with modified formulations have been prepared to achieve long term stability while maintaining high activity.