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

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.