Electrically driven SiC-based structured catalysts for intensified reforming processes

This article presents a study on the electrification of reforming processes, in which the heat required for the reaction is directly supplied by the surface of the structured catalyst, realized by using commercial silicon carbide (SiC) heating elements as catalyst carriers, so eliminating all resistances to heat transfer. Three commercial ceramic supports were loaded with a 5 wt% nickel and tested in the steam reforming reaction. The best performance was obtained by the silica-mullite composite based support with the highest specific surface area. The structured catalyst was prepared by washcoating a SiC heating element, using a slurry based on the silica-mullite composite, subsequently impregnated in a solution of the nickel precursor, and tested in the steam and dry reforming reactions. The experimental tests were properly designed in order to reach the goals of (i) obtaining the kinetic parameters for the MSR reaction, and (ii) evaluating the energy consumption for both processes. The catalysts were characterized by means of X-ray diffraction, specific surface area, ED-XRF, SEM-EDS and Hg porosimetry. The results of the tests demonstrated that is possible to heat the system up to 800 °C, and sustain the reaction obtaining a methane conversion higher than 85 % both in the case of steam and dry reforming. The analysis of the energy consumption in terms of kWh Nm−3H2 has shown that it is comparable with the one of the modern electrolysers. The results of these experiments unequivocally demonstrate that it is possible to realize a process by reversing the flow of heat, from the inside of the catalytic bed to the outside.