The removal enhancement of organic contaminations and optimization of the photocatalytic efficiency by Box-Behnken design using ZnO-TiO2/porous graphene aerogel

• Published in: Environmental science and pollution research international 2023-07, Vol.30 (33), p.81206-81225
• Main Authors: Buu, Ton That, Ngoc, Bo Khanh, Quan, Vo Minh, Hai, Nguyen Duy, Nam, Nguyen Thanh Hoai, Hieu, Nguyen Huu
• Format: Article
• Language: English
• Subjects: Adsorption; Aerogels; Aquatic Pollution; Atmospheric Protection/Air Quality Control/Air Pollution; Catalysts; cost effectiveness; Design of experiments; Dyes; Earth and Environmental Science; Ecotoxicology; Efficiency; Environment; Environmental Chemistry; Environmental Health; Environmental science; Experimental design; Free radicals; Gentian violet; Graphene; Hydrogen peroxide; Nanocomposites; Nitrophenol; Optimization; p-Nitrophenol; Phenolic compounds; Phenols; photocatalysis; Photodegradation; photolysis; Research Article; Scavenging; Self-assembly; thermodynamics; Titanium dioxide; Waste Water Technology; Water Management; Water pollution; Water Pollution Control; zinc; Zinc oxide; Zinc oxides
• ISSN: 1614-7499; 0944-1344; 1614-7499
• DOI: 10.1007/s11356-023-28100-z

In this study, zinc oxide-titanium dioxide/graphene aerogel (ZnO-TiO 2 /GA) was successfully synthesized through a simple and cost-effective hydrothermal self-assembly process. Besides, the surface response model and the experimental design according to the Box-Behnken model were selected to determine the optimal removal efficiency for crystal violet (CV) dye and para-nitrophenol (p-NP) phenolic compound. According to the obtained results, the highest degradation efficiency for CV dye of 99.6% was obtained under the following conditions: pH 6.7, CV concentration of 23.0 mg/L, and catalyst dose of 0.30 g/L. For p-NP, the degradation efficiency reached 99.1% under the following conditions: H 2 O 2 volume of 1.25 mL, pH 6.8, and catalyst dose of 0.35 g/L. Therewithal, kinetic models of adsorption-photodegradation, thermodynamic adsorption, and free radical scavenging experiments were also investigated to propose the specific mechanisms involving the removal of CV dye and p-NP. According to the aforementioned results, the study provided a resulting ternary nanocomposite with great removal performance for water pollutants via the synergetic effects of adsorption and photodegradation processes.