Syngas production from CO2 reforming of ethanol over an Ir/CeO2 catalyst was investigated. Catalysts characterization was conducted by X-ray diffraction (XRD), temperature programmed reduction (TPR), transmission electron microscopy (TEM) and temperature programmed oxidation (TPO). The Ir/CeO2 catalyst was more active and stable toward syngas formation (molar ratio ∼1). The superior catalytic performance was interpreted in terms of the strong interaction between Ir particles and ceria support which was crucial for efficient ethanol/CO2 activation and coke removal on the catalyst surface.

Hydrogen production from ethanol steam reforming over an Rh/CeO2 catalyst was investigated with a stoichiometric feed composition. Ethanol was entirely converted to hydrogen and C1 products (CO, CO2, CH4) at 400°C due to the remarkable C–C bond cleavage capacity of Rh species. The Rh/CeO2 catalyst exhibited stable activity and selectivity without the obvious deactivation during 70h on stream test. Structural analysis of the aged catalysts indicated that the strong interaction between Rh and ceria support efficiently inhibited Rh particles sintering (stable at around 2nm) and coke formation to guarantee catalyst stability.

Steam reforming of propane over a novel Ir/Ce0.75Zr0.25O2 catalyst was investigated. Various techniques such as X-ray diffraction (XRD), temperature-programmed reduction (TPR), high resolution transmission electron microscopy (HRTEM), and oxygen storage capacity (OSC) etc were used to characterize the as-prepared catalysts in order to elucidate the catalyst structure-performance relationship. The doping of ZEO(2) into the CeO2 lattice greatly improved the redox property of the CeO2 by creating more surface oxygen vacancies. Stability test revealed that the Ir/Ce0.75Zr0.25O2 sample exhibited rather stable catalytic behavior for 65 h time-on-stream without obvious deactivation, which was assigned to the efficient prevention of the sintering of the highly dispersed Ir particles through the strong interaction between It and CeO2 support and to the significant resistance to coke deposition due to the excellent OSC of Ce0.75Zr0.25O2 support. (C) 2015 Elsevier B.V. All rights reserved.

Hydrogen production from ethanol is regarded as a promising way for energy sustainable development, which is undergoing an explosive growth over the last decade. Besides operating conditions, hydrogen yield greatly dependent on the nature of metal and the support selected. To date, Rh based catalysts proved to be the most active systems due to the fact that Rh possessed the greatest capacity toward C–C bond cleavage. Support also played a critical role in terms of hydrogen selectivity and stability. MgO, CeO2 and La2O3 etc were evidenced as suitable supports because of their basic characteristic and/or redox capacity. A detailed analysis based on the spectroscopic technique revealed that reaction pathways proceeded along a mono-functional or bi-functional mechanism according to the types of active metal and support. Ethanol dehydrogenation and/or dehydration reaction mainly occurred on the support, and the diffusion/transformation of the intermediates took place at the metal–support interface. Meanwhile, active metal accelerated the decomposition reaction. The observed catalyst deactivation was normally assigned to the coke formation, active metal sintering and/or oxidation as well as the impurity in crude bio-ethanol. Hence, the scope of this review is to address the present progress in ethanol reforming for hydrogen production including catalyst development and the analysis of the reaction mechanism and kinetics in order to shed light on the design of high efficient catalyst systems and the fundamental understanding of ethanol conversion at the molecular level.

Oxidative steam reforming of ethanol was investigated over a supported Ir/CeO2 catalyst in a micro-channel structured reactor. The catalyst coating was successfully deposited on the channel and showed a remarkably high homogeneity and an excellent adherence to the stainless steel platelets leading to stable performance during long time runs. Both the activity and hydrogen selectivity in the micro-structured reactor was found higher than in a conventional fixed-bed reactor due to the rapid mass and heat transfer hence being extremely promising for hydrogen production in micro fuel cell application. (C) 2014 Elsevier B.V. All rights reserved.