On the selective oxidation of H2S by heavy loaded Nanoparticles Embedded in Mesoporous Matrix (NEMMs)

[Display omitted] •Facile methodology for making Nanoparticles Embedded in Mesoporous Matrix (NEMM).•FexOy/meso-SiO2 catalysts with sizes of 2−20 nm and loadings up to 82 w.t.% FexOy.•NEMMs performance towards H2S selective oxidation over GHSV: 82,820−244145 h−1.•100 % conversion and 97 % selectivity achieved at 150 °C and 166,640 h−1.•NEMMs display high structural stability over multiple sulfidation/oxidation cycles. In this work, we present a facile methodology for catalysts synthesis which allows for achieving active component loadings up to 82 w.t.% while controlling the size (2 nm–20 nm), morphology and phase. The active component nanoparticles are synthesized to the desired size, shape and morphology in an organic environment and then are transferred to an aqueous environment wherein the support is grown around the nanoparticles. We demonstrate the efficacy of this methodology in the selective oxidation of H2S using γ-Fe2O3/meso-SiO2 as the catalyst. Our results suggest that the optimal catalyst comprised of γ-Fe2O3 spherical nanoparticles of size ranging from 5 to 7 nm, at a loading ranging from 57 to 73 w.t.%, achieve 100 % conversion and >90 % selectivity towards sulfur at the gas hourly space velocities of 166,640 h−1 and 82,820 h−1. The methodology presented herein can be extended to many other catalytic systems.