Effect of the support on the CO2 hydrogenation to C2-C4 products
Mariana B. S. Felgueiras, M. Fernando R. Pereira, O.S.G.P. Soares
Abstract
Carbon dioxide (CO2) is one of the main drivers of climate change, and, in this sense, it is essential to develop technologies to transform excess CO2 into valuable chemicals and fuels to protect the environment and reduce dependence on fossil fuels. This study assesses the most suitable supports for Fe, Co, K and Na catalysts to achieve high CO2 conversion and selectivity to C2-C4 products through modified Fischer-Tropsch synthesis. For that, multimetallic catalysts (Fe, Co, K, Na) supported on carbon and aluminium oxide materials were synthesised and applied in the CO2 hydrogenation reaction. The catalysts were chemically and texturally characterized, and the catalytic tests were carried out at 350 ºC, 20 bar and under H2, CO2 and N2 flows. Activated carbon (AC)-supported catalysts recorded the lowest values for CO2 conversion and selectivity to C2-C4 and those supported on carbon nanotubes (CNT) revealed to be the most promising as they demonstrated results identical to those obtained for materials supported on Aℓ2O3. In respect to the metallic phase, Na-containing catalysts promote the highest CO2 conversion, whereas Fe catalysts have the highest selectivity in the C2-C4 products.