Iron-organic frameworks-derived iron oxide adsorbents for hydrogen sulfide removal at room temperature

We have reported iron-based MOFs by sonication of organic linkers with a freshly prepared iron hydroxide, which served as templates to yield iron oxide adsorbents after calcination. The PXRD analysis confirmed the presence of alpha-Fe2O3 and Na2SO4 in MOF-derived adsorbents. The XPS analysis confirmed the presence of both Fe2+ and Fe3+ species in all MOFs and derived iron oxide adsorbents. These adsorbents were studied for H2S removal in both dry and moist conditions at room temperature. The iron terephthalate MOF-derived iron oxide adsorbent showed the maximum adsorption capacity of 36.2 mg g(-1) at moist conditions. The H2S removal process over iron oxide adsorbents was governed by the oxidation of H2S into sulfur and sulfates by Fe3+ and adsorbed oxygen. The spent adsorbent was regenerated by NH4OH to produce ammonium sulfate (liquid fertilizer), which is a novel approach to convert waste into value-added products.

Automated summary

Iron-based MOFs were synthesized through sonication of organic linkers with freshly prepared iron hydroxide, serving as templates for iron oxide adsorbents after calcination. The adsorbents exhibited significant adsorption capacity for H2S removal, with iron terephthalate MOF-derived iron oxide showing the highest capacity. The spent adsorbent was regenerated by NH4OH to produce ammonium sulfate, providing a novel method to convert waste into value-added products.