Catalytic decomposition of CH4 over NiO–Al2O3–SiO2 catalysts: Influence of catalyst preparation conditions on the production of H2

This paper presents the synthesis and characterization of NiO–Al2O3–SiO2 catalysts prepared by co-precipitation method and the catalytic activities estimated for the production of H2 by CH4 decomposition. The physico-chemical characteristics are evaluated by XRD analysis, TPR and O2 pulse chemisorption, XPS, CHNS, SEM/EDAX, TEM and BET-surface areas of fresh and used forms of catalysts. XRD studies revealed the presence of hydrotalcite-like precursors in oven dried form and produced dispersed NiO species upon calcination in static air at 450 °C. The catalyst compositions for NiO–Al2O3–SiO2 system are optimized based on various parameters such as varying Ni loadings, change in Al/Si ratios, precipitation at different pH and finally choice of precursors on CH4 decomposition activities. Based on the results it is concluded that the composition of NiO–Al2O3–SiO2 and preparation conditions played a key role in the decomposition of CH4. The optimized compositions are established for the production of H2 that can be utilized in fuel cell applications.