Hybrid plasma-sono-coprecipitation dispersion of NiMo nanocatalyst over functionalized multiwall carbon nanotube used in hydrodesulfurization of thiophene

Abstract

To evaluate the effect of non-thermal plasma and ultrasound treatment on the catalytic physicochemical properties and hydrodesulfurization activity, a series of NiMoW/FMWCNT nanocatalysts (4%NiO, 12%MoO3, and 6% WO3) were prepared via co-precipitation method. The co-precipitated and treated by ultrasound or plasma-ultrasound nanocatalysts were characterized using XRD, FESEM, EDX dot-mapping, BET and FTIR techniques. The XRD data confirmed the formation of NiO, WO3, and Mo2C as the crystalline phase on carbon support. The results indicated ultrasound irradiation and non-thermal plasma treatment have significant influences on phase structure, morphology, and surface area. The optimum amount of applied voltage of plasma was found to be 500 V in which the maximum surface area and well-dispersion of the active phase were found. Further applied plasma voltage led to a decrease in catalytic activity due to the higher support-metal interaction and unpleasant distribution of the particles on nanocatalyst surface. The plasma–ultrasound hybrid synthesis method was able to eliminate 100% of sulfur in the initial solution of thiophene during hydrodesulfurization process.