THEME: "Exploring Critical Breakthroughs in Catalysis and Chemical Engineering"
Sidi Mohamed Ben Abdellah University, Morocco
Title: Novel River Sediment@ZnO-Co nanocomposite for photocatalytic degradation and COD reduction of crystal violet under visible light
Tanji Karim
Doctor in Chemistry and engineering process. Three years as a temporary
professor at High School of Technology University Sidi Mohamed Ben Abdellah University,
Fez, Morocco. Tanji does many investigations in the catalysis field for
wastewater treatment using adsorption, wet oxidation, and photocatalysis.
Currently, works on the development of a new photocatalysts based on zinc
spinel phases for wastewater treatment.
This work
aims to evaluate the adsorption and photocatalysis efficiency of the composite
river Sediment (S)@Cobalt-doped ZnO (ZCo) with two weight ratios of 10 and 20%
of ZCo/river sediment. The S@ZCo was successfully prepared using the chemical
precipitation method followed by the wet impregnation method. The structure and
morphology of the synthesized materials were examined using, X-ray diffraction
(XRD), Fourier transform infrared spectroscopy (FTIR), X-Ray fluorescence
technique (XRF), BET surface area, scanning electron microscopy (SEM), and
UV–Vis diffuse reflectance spectra (DRS). The Box-Behnken model was effective
for modeling the experimental data of crystal violet dye (CV) photodegradation
according to the analysis of variances (ANOVA) results and showed that the ZCo
amount and CV solution pH are the most influencing parameters on the process
efficiency. A total removal (100%) of CV has been attained for 60 min with a
high percentage (93%) of chemical oxygen demand (COD) removal using S@ZnO-Co20%
under visible light illumination and the optimum conditions obtained from the
Box-Behnken. S@ZCo20% displayed high stability after five cycles. Furthermore,
the activity of superoxide ions (O2·-) and hydroxyl radicals (OH.) as the
responsible spices for CV degradation were well affirmed by the radical’s
scavenging tests. Overall, these discoveries could offer additional
contributions to the elaboration of new composites based on modified ZnO for various potential applications and
especially photocatalysis.
Keywords
River sediment; ZnO; Cobalt; Wet impregnation; RSM
methodology; Photodegradation.