Evaluation of different operating parameters in the photocatalytic oxidative desulfurization process to degrade dibenzothiophene sulfur compound in the presence of BiOI/CeO2/NaY zeolite heterojunction

Abstract

In this study, BiOI/CeO2/NaY zeolite composite was applied to remove sulfur compounds in gasoline model fuel to reduce environmental pollution and increase clean fuel production. First, the parent NaY zeolite was transformed into mesoporous zeolite during the sequential dealumination-desilication process. Then, the binary structures of BiOI/NaY zeolite and BiOI/Meso NaY zeolite were successfully synthesized by hydrothermal method. Next, in order to increase the photocatalytic performance in the desulfurization process, cerium ion was impregnated on the synthesized binary samples, so that the ternary combination of BiOI/CeO2/Meso NaY zeolite was investigated for the first time in the application of photocatalytic oxidative desulfurization in the presence of air as an oxidant. Furthermore, XRD, XPS, FT-IR, FE-SEM, EDS-MAP, TEM, BET, UV–vis DRS, PL and EIS analyzes were used to identify the structure, evaluate the compounds and determine the performance of the synthesized samples. In addition, the effect of operational parameters in the photocatalytic oxidative desulfurization process including photocatalyst dosage, model fuel concentration, reaction temperature, type of oxidant, type of extractant, the volume ratio of model fuel to extractant, different sulfur compounds, reusability and scavengers were assessed. The results showed that the BiOI/CeO2/Meso NaY zeolite ternary sample with an amount of 50 mg at the temperature of 25 ℃ and the concentration of 500 ppm of the sulfur compound was able to eliminate 98.8 % of the pollutant in 30 min. Moreover, the effect of the active species in the process was evaluated using various electron-removing agents to remove the sulfur compound from the fuel on an industrial scale.