Excellent catalytic performance over reduced graphene-boosted novel nanoparticles for oxidative desulfurization of fuel oil

Abstract

Three new inorganic–organic hybrid nanocomposites (In–WO3@rGO, Mo–WO3@rGO, and Mn–WO4@rGO) were synthesized by hydrothermal method and applied for recoverable and efficacious ODS process of real oil. The physicochemical analysis of novel nanocatalysts was conducted by various techniques, i.e., powder X-ray diffraction, fourier transform infrared spectroscopy, scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy and thermogravimetric analysis. XRD and SEM analyses depicted that the nanoparticles (In–WO3, Mn–WO4, and Mo–WO3) were well embellished on the exterior of reduced GO with an amazing morphology, having a crystallite size of less than 40 nm. The catalytic activity of nanocomposites was scrutinized for real fuel (diesel and kerosene) and model fuel (DBT) using the radical initiator mechanism of the ODS pathway. Excellent efficiency can be obtained under optimized conditions using 0.1 g catalyst, 1 mL oxidant (H2O2), and100 ppm DBT at 40°C with a time duration of 180 min. Various factors such as time, DBT concentration, catalyst amount, oxidant amount, and temperature that affect catalytic activity directly or indirectly were also studied. A pseudo-first-order kinetics model was followed, and due to spontaneous reaction, a negative value of ΔG was observed with an activation energy of 6.54 kJ/mol for Mo–WO3@rGO, which is lower than that of the other two hybrids. The synthesized nanohybrids showed remarkable durability and recovery up to five times for the ODS process without significant change in proficiency.