The current study
comprises the successful synthesis of a Ni-WO
3
@g-C
3
N
4
composite as an efficient and
recoverable nanocatalyst for oxidative desulfurization of both model
and real fuel oils. The physiochemical characterization of the synthesized
composite was confirmed via Fourier transform infrared spectroscopy,
X-ray diffraction, scanning electron microscopy (SEM), energy-dispersive
X-ray spectroscopy, and thermogravimetric analysis. SEM results showed
that Ni-WO
3
particles were well-decorated on the g-C
3
N
4
surface with an interesting morphology as appeared
on the surface like spherical particles. The obtained findings revealed
that 97% dibenzothiophene (DBT) removal can be achieved under optimized
conditions (0.1 g of the catalyst, 1 mL of an oxidant, 100 mg/L DBT-based
model fuel, a time duration of 180 min, and a temperature of 40
°
C). Additionally, the catalytic activity for real fuel
was also investigated in which 89.5 and 91.2% removal efficiencies
were achieved for diesel and kerosene, respectively, as well as fuel
properties following ASTM specifications. A pseudo first-order kinetic
model was followed well for this reaction system, and the negative
value of Δ
G
was due to the spontaneous process.
Additionally, the desulfurization study was optimized via a response
surface methodology (RSM/Box–Behnken design) for predicting
optimum removal of sulfur species by drawing three-dimensional RSM
surface plots. The Ni-WO
3
@g-C
3
N
4
proved
to be a promising catalyst for desulfurization of fuel oil by exhibiting
reusability of five times with no momentous decrease in efficiency.