Hydrogen production through oxidative steam reforming of acetic acid over Ni catalysts supported on Ceria-based materials

Oxidative steam reforming allows higher energy efficiency and lowers coke deposition compared to traditional steam reforming. In this work, CeO2-based supports have been prepared with Ni as the active phase, and they were tested in the oxidative steam reforming of acetic acid. The in-fluence of the O2/AcOH molar ratio (0 - 0.3) has been evaluated over Ni/CeO2. The results stated that by increasing oxygen content in the feeding mixture, acetic acid conversion increases, too with a decrease in coke deposition, and hydrogen yield. To have a proper balance between the acetic acid conversion and the hydrogen yield an O2/AcOH molar ratio of 0.075 was selected to study the catalytic performance of Ni catalysts over different supports: commercial CeO2, a novel mesostructured CeO2, and CeO2-SBA-15. Due to higher Ni dispersion over the support, the mesostructured catalysts allowed higher acetic acid conversion and hydrogen yield compared to the non-porous Ni/CeO2. The best catalytic performance and the lowest coke formation (120.6 mgcoke·gcat 1·h 1), were obtained with the mesostructured Ni/CeO2. This sample reached almost complete conversion (> 97%) at 500 °C, maintaining the hydrogen yield over 51.5% after 5 h TOS, being close to the predicted value by the thermodynamic equilibrium due to the synergistic co-ordination between Ni and CeO2 particles.