Optimization of oxidative desulfurization reaction with Fe2O3 catalyst supported on graphene using box-behnken experimental method

Abstract

In this study, the catalyst activity of Fe2O3 supported on Graphene for Iraqi gas oil oxidation desulfuri-zation (ODS) by hydrogen peroxide (H2O2) was investigated. The prepared catalyst was synthesized by wet impregnation for ferric nitrate as a Fe2O3 precursor while Graphene represented as catalyst sup-port. The synthesized catalyst was characterized by XRD, FTIR, and EDS analysis. The experiments were designed according to three-level for three variables by Box-Behnken experimental design; Stir-ring time, catalyst dosage and temperature while the sulfur removal efficiency acts as experiment re-sponse. Catalyst activity was studied by ODS reaction for Iraqi gas oil (sulfur content 9400 ppm) at temperature range (40-60 °C), stirring time (160-240 minutes) and catalyst dosage (0.5-2.5 g), the re-sults show maximum sulfur removal efficiency 90% at stirring time, catalyst dosage and temperature 240 min, 1.5 g, and 60 °C, respectively. ANOVA analysis shows the important effect of each independ-ent variable on sulfur removal efficiency (response) as following influential order; stirring time, reac-tion temperature and catalyst dosage. Kinetics calculation showed that the ODS reaction obeys pseudo first-order reaction with reaction rate constant equal 1.0837, 1.5893, and 2.5053 at temperature 40, 50, and 60 °C, respectively, while activation energy equal 36.26 kJ/mol.