LaxNiyOz/MAS-9 Catalysts with High Ni0 Dispersion and Hydrothermal Stability for CH4/CO2 Reforming

Mesoporous aluminosilicate (designated as MAS-9) was synthesized through assembling ZSM-5 nanocrystallites as precursors with P123 as surfactant, which exhibited excellent properties, such as large specific surface area, big pore volume, uniform pore distribution, and high hydrothermal stability. A series of LaxNiyOz/MAS-9 catalysts for CH4/CO2 reforming were prepared by the sol-gel method. Support and catalysts were characterized using N-2-adsorption, X-ray diffraction, Fourier transform IR, inductively coupled plasma-mass spectrometry, H-2 temperature-programmed reduction, thermogravimetric/differential scanning calorimetry, and high-resolution transmission electron microscopy techniques. The adjustment of the La/Ni molar ratio will be beneficial to the enhancement of Ni-0 particle dispersion and decrease of particle size, which increased the catalytic activity and the resistance to carbon deposition. Under the condition of an atmospheric pressure at 850 degrees C and a gas hour space velocity of 3.2 x 10(4) mL.g(-1).h(-1), the conversion of CH, and CO2 over LaNi2Ox/MAS-9 catalyst was 100%, and the selectivities of H-2 and CO were 95% and 99%, respectively. In addition, the stability test of LaNi2Ox/MAS-9 catalyst for 145 h revealed that the conversion of CO2 (100%), the selectivity of H-2 (95%) and CO (99%), with a H-2/CO ratio of 0.96 as well as carbon yield (ca. 1%) almost kept constant although conversion of CH4 slightly decreased to 94%. The mesoporous structure of MAS-9 kept intact after 145 h CH4/CO2 reforming. Therefore, LaNi2Ox/MAS-9 was a promising catalyst for CH4/CO2 reforming.