Characterization and catalytic activity of NiO/mesoporous aluminosilicate AlSBA-15 in conversion of some hydrocarbons

摘要

Mesoporous aluminosilicate AlSBA-15 was synthesized and adopted as a support for NiO with 3, 6 and 9wt.% loadings. Characterization of various samples was performed through XRD, FTIR, DSC-TGA, TPR, SEM and TEM techniques. Textural and morphological characteristics were examined using N2adsorption–desorption isotherms. Catalytic activities were measured in cumene cracking for parent AlSBA-15 and inn-hexane and toluene cracking and cyclohexane dehydrogenation for supported NiO samples. Uniformity of the ordered 2D-hexagonal structure of AlSBA-15 was evident even after loading with NiO. NiO and NiOOH phases could be detected particularly in the sample containing 9wt.% NiO. TPR profile of solid loaded with 3wt.% NiO sample showed negative peaks at 400 and 600°C, related to hydrogen spillover on reduced sample. Selectivity towardsn-hexane and toluene cracking increased with both temperature and metal oxide loading, achieving 100% at 350°C. In cyclohexane dehydrogenation, the sample loaded with 3wt.% NiO was the most active and selective one towards benzene formation.