Novel photocatalyst system to deep desulfurization of petroleum model and gas condensate by Box–Behnken design

Abstract

In this research, cobalt (Co)/molybdenum (Mo) and nickel (Ni) doped with titanium dioxide (TiO2) were loaded onto multi-walled carbon nanotubes (MWCNTs). Then, the magnetization catalyst, iron oxide (Fe3O4), was loaded on them, which was used for the deep desulfurization of dibenzothiophene (DBT). These catalysts were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, differential reflectance spectroscopy, and Brunauer–Emmett–Teller, Barrett–Joyner–Halenda, and vibrating sample magnetometer techniques. The photocatalytic activity of these catalysts was experienced under visible light using DBT. The response surface methodology based on the Box–Behnken design was used to evaluate parameters, including catalyst dosage (g), time (min), and concentration of DBT (mg L−1). The highest degradation efficiency under optimal conditions for CoMoNi/TiO2/MWCNTs/Fe3O4 catalysts with a catalyst dosage of 0.3 g, a time of 180 min, and a concentration of 50 mg L−1 was 99.99%. Optimum conditions were studied for desulfurization of the gas condensate. The highest desulfurization efficiency (90.33%) was obtained by the CoMoNi/TiO2/MWCNTs/Fe3O4 catalyst.