An experimental investigation of biodiesel steam reforming

The present study constitutes an experimental investigation of biodiesel steam reforming, the main emphasis of which is placed on finding optimum operating conditions in order to avoid catalyst deactivation. Temperature was varied from 600 °C to 800 °C, pressure from 1 bar to 5 bar and the molar steam-to-carbon ratio from 3 to 5. Based on the experimental results, coke formation and sintering are identified as the main deactivation mechanisms. Initiation of catalyst deactivation primarily depends on catalyst inlet temperature and feed mass flow per open area of catalyst. By using a metallic based precious metal catalyst, applying low feed flow rates (31 g/h∙cm2) and a sufficiently high catalyst inlet temperature (>750 °C) coking can be minimized, thus avoiding catalyst deactivation. A stable product gas composition close to chemical equilibrium has been achieved over 100 h with a biodiesel conversion rate of 99%.