Microwave assisted steam reforming in a high efficiency catalytic reactor

The current H2 production in the EU (>27 kt/d) is almost entirely from natural gas via Methane Steam Reforming (MSR), a strongly endothermic catalytic process, carried out in packed-bed tubular reformers at 750–900 °C, with considerable CO2 emissions. In this context, the application of renewable electricity to MSR offers interesting perspectives for a reduced environmental footprint. The use of microwaves (MW) may result in efficient and faster method for generating the heat directly inside the catalytic volume. In this work, the role of the reactor configuration in the MW-assisted MSR has been investigated, by performing dedicated experimental tests in which a Ni-based catalyst (7 wt% with respect to the washcoat), prepared starting by silicon carbide monoliths, was tested in two different reactors. The results showed that the CH4 conversion showed a good approach to the thermodynamic equilibrium values starting at about 750 °C at a value of gas hourly space velocity (GHSV) of 5000 h−1 in the tests performed with the optimized reactor configuration. The energy efficiency of the two systems was about 50% and 73%, for the classical and optimized configuration respectively, and the latter had an energy consumption of 2.5 kWh/Nm3H2 at 750 °C.