Nano-Hollow Zeolite-Encapsulated Highly Dispersed Ultra-Fine Fe Nanoparticles as Fischer–Tropsch Catalyst for Syngas-to-Olefins

Abstract

A nano-hollow zeolite-encapsulating ultra-fine Fe nanoparticle catalyst denoted as Fe@n-hS-HT was successfully synthesized through a simple water steam treatment of the Fe@n-hS catalyst prepared by the “dissolution–recrystallization” (D-R) method. The Fe@n-hS-HT catalyst had a hierarchical porous structure and a high dispersion of Fe2O3 particles with a size of 3.4 nm. Furthermore, the results of several characterization methods, such as XRD, HAADF-STEM, and H2-TPR, further demonstrated the transformation of the skeleton Fe in Fe@n-hS into Fe2O3, which was uniformly dispersed in the Fe@n-hS-HT catalyst. Meanwhile, Fe@n-hS-HT had significantly higher selectivity and yield of C2-C4= than the reference catalysts Fe/S and Fe@n-hS, which provided strong proof for the confined catalysis of the metal@zeolite catalyst.