GREEN FUELS FROM BIOGAS VIA TUNED REFORMING/FISCHER-TROPSCH ROUTE: PERFORMANCES OF Rh/CeO2 AND FeOx BASED CATALYSTS

In this study, the catalytic activity of Rh/CeO2-based catalyst supported on ceramic monoliths was probed toward biogas (CH4/CO2=1.5) Steam Reforming (SR) and Oxy Steam Reforming (OSR), varying temperature (700-900°C), S/C (0.3-3) and O/C (0.1-0.5) at fixed Weight Space Velocity (WSV=72,000 Nml·gcat-1·h-1). The structured catalyst exhibited good performances for both the reforming processes. In addition, the OSR offered considerable advantages over SR route, mainly related to the possibility to produce a reformate gas with a desiderable H2/CO ratios. Then, the reformate (CO:CO2=1:1; H2/(CO+CO2)=1.3), was fed to the Fischer-Tropsch reactor, working at 250°C and 20 bar with FeOx-based catalysts (WSV=1,400 Nml gcat-1h-1). The effect of catalytic (ZnO, CuO, MnO) and structural promoters (SiO2, Al2O3, CeO2) on the activity and selectivity into higher hydrocarbons was evaluated. Particularly, iron-manganese-ceria catalyst reached the best catalytic performance in term of both carbon monoxide conversion and selectivity to high hydrocarbons.