Scaling up Ru/NiO-CeO2 CO2 methanation catalysts. Comparison of 3D printed steel and carbon monolith supports

The CO 2 methanation reaction was studied using supported catalysts on monolithic structures under high space velocities (11,000 – 56,700 h -1 ), and the effect of the exothermicity of the reaction on the catalyst temperature and the catalytic performance was evaluated. A Ru/NiO-CeO 2 nanoparticles (NP) catalyst was supported on steel and carbon monoliths, which were fabricated using 3D printing. The results demonstrate that the performance of the active phase is affected by the support material. Better results were achieved with carbon monoliths than with steel monoliths, due to the lower thermal conductivity of carbon (0.43 and 1.20 W m -1 K -1 , respectively). Steel dissipates the energy released by the exothermic methanation reaction more effectively, while carbon monoliths retain this energy within the structure, favoring local heating of the active phase. The positive effect of carbon support leads to energy savings, as the power consumed to heat the furnace remains constant regardless of the support material. Meanwhile, the energy released by the reaction is dissipated less and used more efficiently by carbon supports. The design of the channel network of supports has a minimal impact on catalytic performance under the high flow rates employed in this study.