Synthesis of a new nanocomposite based on sandwich-type silicotungstate and polyvinyl alcohol with superior catalytic activity for deep desulfurization of real/thiophenic mode fuel

Abstract

For preparation of ultra-clean real gasoline fuel, a new cone-like amphiphilic nanocomposite (TBASi₂W₁₈Cd₄@PVA) has been synthesized by supporting cadmium containing sandwich-type silicotungstate polyoxometalate ((n-C₄H₉)₄N)₇H₅Si₂W₁₈Cd₄O₆₈ (TBASi₂ W₁₈Cd₄) on polyvinyl alcohol (PVA) as an organic-inorganic hybrid nanocatalyst for catalytic oxidative desulfurization (CODS) of real fuel and thiophenic model fuels. The synthesized samples were characterized using elemental analysis, FT-IR, UV–vis, ¹¹³Cd NMR, ²⁹Si NMR, XRD and SEM techniques. The catalytic activity of TBASi₂W₁₈Cd₄@PVA nanocomposite was tested on thiophenic model fuels and real gasoline fuel in the presence of CH₃COOH/H₂O₂ as an oxidant. After examining TBASi₂W₁₈Cd₄@PVA nanocomposite in the CODS processes, optimum effective properties were investigated. The average efficiency of the nanocatalyst (TBASi₂W₁₈Cd₄@PVA) was 98% by optimum values of the properties (catalyst dosage, temperature, oxidation system, different types of catalysts). It has great reusability with 96% of effectiveness after five runs. The CODS mechanism is proposed based on the obtained results, the kinetics were in agreement with the pseudo-first-order model. Based on the obtained results, it could be considered as an effective and industrial-scale nanocatalyst for the desulfurization of refractory sulfur compounds in extremely mild conditions.

Graphical Abstract

Keywords:

• Sandwich-type heteropolyatom
• nanocomposite
• nanocatalyst
• thiophenic model fuel
• gasoline

Disclosure statement

No potential conflict of interest was reported by the authors.