Humic Acid Glazed Magnetite Material for the Adsorptive Desulfurization of Model Fuel.

Abstract

Impact of climate change that stems from gaseous emissions require sustainable materials to eliminate sulfur. This study involves the modification of humic acid with magnetite nanoparticles (Fe₃O₄ NPs) by a microwave-assisted synthesis of an absorbent with reasonable pore volume and diameter for elimination of thiophenic compounds from fuel. The magnetic nano adsorbent designated Fe₃O₄@HA was characterized using advanced spectroscopic techniques, while their structure and morphology were analyzed through DLS, XPS, XRD, FT-IR, TGA, FESEM-EDX, VSM, and BET-N₂ techniques. These findings indicated that the synthesized magnetic nano adsorbent (Fe₃O₄@HA) has appropriate oxygen functionalities with a specific surface area of 335 m² g^-1 and a mesoporous structure with a pore diameter of 9 nm. The adsorption capacity for sulfur was determined to be 62.73 mg g^-1. The kinetic and isotherm models, coupled with thermodynamic characteristics, confirmed that the adsorption of sulfur onto the adsorbent was spontaneous, exothermic, and followed pseudo-first-order kinetics. The adsorbent material demonstrated reusability for sulfur adsorption for up to six cycles. The economic and environmental advantages of the preparation process provide humic acid modified with magnetite nanoparticles (Fe₃O₄ NPs) as an interesting candidate for real-world applications.