Synthesis and characterization of antibacterial chromium iron oxide nanoparticle‐loaded activated carbon for ultrasound‐assisted wastewater treatment

Abstract

The aim of this study was to evaluate the surface adsorption capacity of CrFeO 3 nanoparticle-loaded activated carbon (CrFeO 3 -NPs-AC) for the removal of a cationic dye (methyl violet, MV). CrFeO 3 -NPs were hydrothermally synthesized and loaded on AC followed by characterization using X-ray diffraction, fieldemission scanning electron microscopy and energy-dispersive and Fourier transform infrared spectroscopies. The CrFeO 3 -NPs were tested for in vitro antibacterial activities against Gram-positive (Staphylococcus aureus) and Gram-negative (Pseudomonas aeruginosa) bacteria. Minimum inhibitory and minimum bactericidal concentrations of CrFeO 3 -NPs-AC were obtained to be 50 and 100 μg ml , respectively, against S. aureus and 25 and 50 μg ml −1 against P. aeruginosa. These results indicated the antibacterial properties of CrFeO 3 -NPs-AC. To investigate the adsorption process, several systematic experiments were designed by varying parameters such as adsorbent mass, pH, initial MV concentration and sonication time. The adsorption process was modelled and the optimal conditions were determined to be 0.013 g, 7.4, 15 mg l −1 and 8 min for adsorbent mass, pH, MV concentration and sonication time, respectively. The real experimental data were found to be efficiently explained by response surface methodology and genetic algorithm model. Kinetic studies for MV adsorption showed rapid sorption dynamics described by a second-order kinetic model, suggesting a chemisorption mechanism. Then, the experimental equilibrium data obtained at various concentrations of MV and adsorbent masses were fitted to conventional Langmuir, Freundlich, Temkin and Dubinin-Radushkevich isotherm models. Dye adsorption equilibrium data were fitted well to the Langmuir isotherm. From the Langmuir model, the maximum monolayer capacity was calculated to be 65.67 mg g −1 at optimum adsorbent mass.

Removal of hexavalent chromium from wastewater using supported liquid membrane: synthesis of chromium‐iron complex through electrochemical reaction

“…The IR bands near 418, 457, 472 and 547 cm −1 corresponds to the Cr-O bond stretching vibration (Musi et al, 1999;Abdullah et al, 2014). A peak near 472 and 550 cm −1 corresponds to metaloxygen stretching vibration (Gadsden, 1975;Basavaraja et al, 2011;Bazrafshan et al 2018). All the observed peaks are well in agreement with referred literatures.…”

“…A peak near 472 and 550 cm −1 corresponds to metal‐oxygen stretching vibration (Gadsden, 1975; Basavaraja et al , 2011; Bazrafshan et al . 2018). All the observed peaks are well in agreement with referred literatures.…”

Synthesis of CuS and ZnO/Zn(OH)2 nanoparticles and their evaluation for in vitro antibacterial and antifungal activities

“…The filter paper discs impregnated in the NPs solution (50 μL of 600 μg ml −1 ) were put at different positions on the agar surface. The plates of Aspergillus oryzae were incubated at 37 °C for 48 h . Finally, the antifungal activities of the NPs were evaluated by measuring the inhibition zone diameter of the fungi.…”

Visible‐light‐driven photocatalytic degradation of fenpyroximate in rotating packed bed reactor using Fe3O4@PbS@Ni2P magnetic nanocomposite photocatalyst: Response surface modelling and optimization

“…Rapid progress in agriculture is concomitant with the extensive application of herbicides and pesticides, the subsequent toxicity and stability of which lead to the generation of hazardous problems for humans, animals and the environment . Their potential for entering surface water and groundwater is a great global worry . Their complex structure and strongly recalcitrant nature result in their difficult and non‐complete elimination, while most conventional procedures like adsorption just segregate the pesticides rather than treat them, and more efficient methods like biological remediation have lower removal percentages especially in a reasonable time .…”