Surface chemistry and catalytic performance of amorphous NiB/H beta catalyst for n-hexane isomerization

摘要

The amorphous NiB nanoparticles were synthesized and a novel type of NiB/H beta catalyst was prepared for the isomerization of n-hexane. The optimum preparation conditions were investigated and the effect of preparation conditions on the surface chemistry information of catalysts was characterized by XRD, N-2 sorption studies, XPS, TPD and other related means. It was demonstrated that the loading amounts of NiB have effect on textural properties and the acid properties of surface. The loading amounts of NiB were also related to the amount of strong Lewis acid sites and the ratios of weak acid to strong acid of samples. Meanwhile, calcination temperatures of samples were closely associated with the structure of active components that function as metal centers. When the loading amount of NiB was 5 wt.% and calcination temperature was 200 degrees C, the catalyst had proper surface acidity sites and metal active sites to provide suitable synergistic effects. The mechanism for n-hexane isomerization was also investigated and the existence of unique structure of B-Ni-H was proved, which could provide good hydrogenation dehydrogenation functions. (C) 2016 Elsevier B.V. All rights reserved.