Synthesis of Organic-Inorganic Hybrid Nanocomposite Polyoxometalate/Metal Oxide/CS Polymer (PMnW11@TiO2@CS): Nanocatalyst for Oxidative Desulfurization of Real Fuel

A new type of organic-inorganic hybrid nanocatalyst was synthesized by composition of Mn(II)-substituted Keggin-type polyoxometalate (PMnW11), titanium dioxide (TiO2) and chitosan polymer (CS) via sol-gel method. The synthesized nanocomposite (PMnW11@TiO2@CS) was characterized by fouriour transform infrared spectroscopy (FT-IR), X-ray diffraction analysis (XRD), energy dispersive X-ray analysis (EDAX) and scanning electron microscopy (SEM) techniques. PMnW11@TiO2@CS was used as a new hybrid nanocatalyst for catalytic oxidative desulfurization (CODS) of real and model fuel in the presence of CH3COOH/H2O2 in the volume ratio of 1/2 as oxidant system at 35 degrees C after 60 min. On the basis of the suggested CODS system, mercaptan and sulfur content of real fuel could be removed lowered with 97%. The CODS of dibenzothiophene molecules, which are difficult to remove, could be reached to 98%. The main factors affecting on the CODS efficiency were investigated in detail. The PMnW11@TiO2@CS was demonstrated an excellent recyclability performance in the CODS reactions for five times without noticeable decrease in catalytic activity.