Performance of Rh/Al2O3 catalyst in the steam reforming of ethanol: H2 production for MCFC Original Research Article

The steam reforming of ethanol on 5% Rh/Al2O3 catalyst has been investigated to produce H2 adequate to feed a molten carbonate fuel cell (MCFC). The influence of reaction temperature, H2O/EtOH molar ratio, gas hourly space velocities (GHSV) and O2 were investigated in order to maximize the hydrogen content at the outlet of ethanol reformer. Endurance tests to assess the feasibility of a FC system fed by simulated bio-EtOH stream (H2O/EtOH molar ratio=8.4) were also performed. Experiments carried out at MCFC operative conditions allowed to obtain a H2 reach mixture close to 60% on dry basis. In steam reforming (SR) conditions an extensive formation of encapsulated carbon was registered while a great benefits, both in terms of catalyst stability and coke formation were evidenced adding 0.4 vol.% of oxygen in the reaction stream. Oxygen however promoted metal sintering. Consideration on reaction mechanism, mainly investigated to distinguish the reaction pathway influencing the H2 production, is reported.