New Insight into the synthesis of Co- and Ni- based catalyst for ethanol steam reforming

Ni and Co-based catalysts represent the most attractive catalysts for the production of hydrogen by the steam reforming of ethanol (ESR) [1-3]. The performances of such systems depend mainly on metal dispersion that in turn can be affected by several factors, including the preparative route. With the intent to tailor the materials features through the variation of the synthesis parameters, three different synthesis procedures were adopted: a conventional hydrolytic alkoxide sol-gel route (I) a surfactant assisted sol-gel route (II) and (III) a Flame Pyrolysis (FP) method. Two supports were also compared, i.e. SiO2 and ZrO2, characterized by different surface acidities and redox properties, as well as different metal loading. All the catalysts were characterized by various techniques, including X-ray powder diffraction (XRPD), N2 physisorption, scanning electron or transmission microscopy (SEM-TEM-EDX) and temperature-programmed reduction (TPR). The activity testing was done in a home-made micro-pilot plant for ethanol steam reforming under different process conditions. Since the coke formation during the ESR is still an issue, the pysico-chemical properties were also tuned to improve low temperature performance. The high surface area obtained for a surfactant assisted sol-gel route tried to fulfill this requirement. On the other hand, the high temperature synthesis adopted for FP was able to impart suitable thermal resistance to the samples, providing a good metal dispersion and a high metal–support interaction. The preparation method resulted to be powerful tool in driving the formation of a designed material with a delicate balance between the reducibility of the metal phase and a suitable metal dispersion. Biobliography: 1. I. Rossetti et al. Appl Catal B: Environ. 2012, 117-118, 384-396. 2. E. Finocchio et al. Int. J. Hydrogen Energ. 2013, 38, 3123-3225. 3. M. Compagnoni et al. Catal. Sci. Technol. 2016, 6, 6247-6256.