Zn-(BDC) and Zn-(BDC)-NH 2 MOFs: Novel Photocatalysts for Desulfurization of Dibenzothiophene from Fuels

Abstract The paper reports the development of nanostructures of organic-metallic frameworks (MOFs) in the form of Zn(BDC) and Zn(BDC)-NH 2 as potent macroporous photocatalysts for desulfurization of aromatic hydrocarbons (dibenzothiophene) in fuels. The reason for placing amine groups in the Zn-MOF photocatalytic structure was that it increased the interaction between MOF and sulfur compounds. The experiments were designed out by the Box-Behnken method of response surface methodology (RSM) and the process was modelled and optimized. Three independent parameters i.e. concentration of dibenzothiophene, the amount of photocatalyst and light emission time were considered in the experimental design. The interactions between the parameters were also investigated by 2D contour and 3D plots. The optimum removal of DBT (50.40%) resulted under a fuel model containing 50 ppm DBT, desulfurized by 0.060 g of Zn-MOF-NH 2 photocatalyst under visible lamp light for 180 min. The predicted response (DBT removal%) by the RSM model was 50.68%. The amine-modified Zn-MOF exhibited a greater activity in the elimination of DBT due to its active amine groups. The mechanism of photocatalytic desulfurization of DBT over Zn-MOF-NH 2 was proposed. The physical-chemical properties of the MOF samples were further recognized by Fourier Transform Infrared (FTIR), X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET), Field-Emission Scanning Electron Microscopy (FESEM) and Uv-Vis diffuse reflectance spectroscopy (UV-Vis DRS). This study showed that Zn-MOF can be an effective photocatalyst for desulfurization under the visible light of a fuel model.