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Fe 2 O 3 nanoparticles were dispersed onto SiO 2 by impregnating amorphous SiO 2 spheres with Fe(NO 3 ) 3 followed by spray drying and calcination. Interestingly, the amorphous SiO 2 spheres in the sample could be converted into Silicalite-1 nanowires after being hydrothermally treated in the presence of a mixture of ethylenediamine and triethylamine (dual templates) for over 4 days, whereas the Fe 2 O 3 nanoparticles were still highly dispersed on the formed Silicalite-1 nanowires. Meanwhile, a fraction of Fe(III) species entered the zeolitic framework. Relevant characterization was conducted using X-ray fluorescence (XRF), N 2 adsorption–desorption, X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), ultraviolet–visible (UV–Vis) spectroscopy, electron paramagnetic resonance (ESR), X-ray photoelectron spectroscopy (XPS), and H 2 -temperature-programmed reduction (H 2 -TPR). The catalytic properties of the samples were studied using CO oxidation, N 2 O decomposition, and selective reduction of NO as probe reactions. [ABSTRACT FROM AUTHOR]

Abstract: Columned ZSM-5 zeolite monoliths with hierarchical structure and excellent mechanical strength were successfully prepared by a hydrothermal transformation method. The pre-formed extrudates of aluminosilicate embedded with β zeolite were subjected to a hydrothermal synthesis system and the hierarchical porous ZSM-5 zeolite monoliths with the same columned shape were obtained after the hydrothermal treatment. The intra-particle hollow structure formed during hydrothermal synthesis was attributed to the digestion of inner β zeolite accompanying with the growth of ZSM-5 zeolite shell. The related data of X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) analysis, N2-sorption experiment and mercury intrusion prosimetry (MIP), showed ZSM-5 zeolite monolith had enriched multi-porosity and excellent mechanical stability, which contribute to its further application in field of catalysis and separation. The obtained hierarchical ZSM-5 zeolite monoliths showed superior catalytic performance in α-pinene isomerization for their proper acidity and good diffusion, compared with the ZSM-5 zeolite sample prepared from the precursor without β zeolite. [Copyright &y& Elsevier]