PROCESS INTENSIFICATION ROUTES AT CNR-ITAE FOR CO2 CONVERSION TO SYNTHETIC NATURAL GAS USING RENEWABLE HYDROGEN

One of the ambitious objectives of the European Commission is the development of sustainable strategies to reduce greenhouse gas emissions, from power conversion and energy-intensive industrial processes, to reaching climate neutrality by 2050. In this scenario, the conversion of the renewable electrical power into a high-value gaseous (Power to Gas) chemical storage medium such as the Synthetic Natural Gas (SNG), through the hydrogenation of CO2 with renewable H2, represents an important tool to create new opportunities to reuse the captured CO2 as well as to manage the fluctuation of renewable energy. At ITAE in the framework of the RDS project, the activities have been focused on the development of novel conductive structured catalysts and compact Multi-tubular Heat Exchanger Reactor optimized for smaller plant sizes and intermittent or dynamic operation. The results show that structured catalysts based on heat conductive Silicon carbide (SiC) Open Cell Foam can contribute to enhances the methanation process maximizing the specific surface areas for reaction at a high flow rate (GHSV = 47000 h-1 ). Moreover the conductive nature of the foam support help to enhance the axial and the radial heat transport along the reactor allowing easier management of the heat generated by the exothermic reaction (figure 1 b). A CO2 conversion of 71.1% and a CH4 selectivity of 94,2% were achieved, while overall methanation productivity of 260 NL h-1 (11.1 NL h-1gcat.-1 ) was attained. Moreover, an operating pressure of 3 bar slightly improves the SiC based catalyst performances, a CO2 conversion of 77.1% and a CH4 selectivity of 95,6% were obtained while the overall CH4 productivity increase up to 285 NL h-1 (12.1 NL h-1 gcat.-1 ).