Effect of UVc and UVA Photocatalytic Processes on Tetracycline Removal Using Cus-Coated Magnetic Activated Carbon Nanocomposite: A Comparative Study

In this study, we synthesized a novel MAC nanocomposite using almond’s green hull coated with CuS. The whole set of experiments have been conducted inside a batch (discontinuous reactor system) at room temperature. The effectiveness of different parameters in tetracycline removal pH (3, 5, 7, and 9), pollutant concentration (5–100 mg/L), nanocomposite dosage (0.025–1g/L), and contact time (5–60min) using newly synthesized nanocomposite were investigated. Based on the results, in the optimal conditions of pH = 9, nanocomposite dosage of 1g/L, pollutant concentration of 20 mg/L, contact time of 60 min, and room temperature, 95% removal efficiency was obtained. In MAC/CuS/UVc process, the removal of COD and TOC were 76.89% and 566.84% respectively meanwhile, these values in MAC/CuS/UVA process were 74.19% and 62.11%, respectively. The results of nanocomposite stability and magnetic recovery illustrated that the removal efficiency was reduced by 1.5% in the presence of UVc and 5% in the presence of UVA lights during all six cycles. Therefore, this nanocomposite was highly capable of recycling and reuse. It can be concluded that considering the high potential of the synthesized nanocomposite, the photocatalytic efficiency of the MAC/CuS/UVc process in tetracycline synthesis was higher than MAC/CuS/UVA process.

Photodeposition of Silver on Zinc/Calcium Ferrite Nanoparticles: A Contribution to Efficient Effluent Remediation and Catalyst Reutilization

The efficient photodegradation of textile dyes is still a challenge, especially considering resistant azo dyes. In this work, zinc/calcium mixed ferrite nanoparticles prepared by the sol–gel method were coupled with silver by a photodeposition method to enhance the photocatalytic potency. The obtained zinc/calcium ferrites are mainly cubic-shaped nanoparticles sized 15 ± 2 nm determined from TEM and XRD and an optical bandgap of 1.6 eV. Magnetic measurements indicate a superparamagnetic behavior with saturation magnetizations of 44.22 emu/g and 27.97 emu/g, respectively, for Zn/Ca ferrite and Zn/Ca ferrite with photodeposited silver. The zinc/calcium ferrite nanoparticles with photodeposited silver showed efficient photodegradation of the textile azo dyes C.I. Reactive Blue 250 and C.I. Reactive Yellow 145. Subsequent cycles of the use of the photocatalyst indicate the possibility of magnetic recovery and reutilization without a significant loss of efficiency.

SPION-decorated organofunctionalized MCM48 silica-based nanocomposites for magnetic solid-phase extraction

(a) Cubic structures formed by CTAB above critical micellar concentration used as a template to generate highly ordered mesoporous silica. (b) Photo showing the magnetic recovery of MCM48/SPION/C8 nanocomposite in 60 s.

Synthesis and characterization of ZnO-TiO2/CoFe2O4 hollow photocatalyst: Magnetic recovery and highly efficient photocatalytic performance

TiO2 has been known as an excellent semiconductor photocatalyst for wastewater treatment purposes. But, its visible light efficiency is low and cannot be easily recovered from the reaction mixture. In order to overcome these major disadvantages, a novel hollow magnetically recoverable ZnO-TiO2/CoFe2O4 photocatalyst is synthesized by the sol–gel and layer self-assembly methods. The synthesized photocatalyst was characterized by means of X-ray diffractometer (XRD), Transmission electron microscopy (TEM), Vibrating sample magnetometer (VSM), Fluorescence spectrometer (FL), and UV-Vis/DRS techniques. Complete degradation of rhodamine B is attained in the presence of ZnO-TiO2/CoFe2O4 photocatalyst under the irradiation of ultraviolet and sunlight within 90[Formula: see text]min. The photocatalyst can be repeatedly reused for five times without significantly diminishing of its photocatalytic performance.