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In this work, Ti-Sn-Sb/γ-Al 2 O 3 particle electrodes were prepared and employed for the degradation of oxytetracycline (OTC) by three-dimensional electrocatalytic technology. Factors associated with the preparation of Ti-Sn-Sb/γ-Al 2 O 3 particle electrodes were investigated. The effects of initial concentration, conductivity, pH value, aeration intensity, current density, plate spacing, and particle electrode dosage on OTC removal were studied. The removal rate of OTC and total organic carbon were achieved approximately 92.0% and 41.0% under the optimal operating condition, respectively. In addition, Ti-Sn-Sb/γ-Al 2 O 3 particle electrode was analyzed by Fourier Transform Infrared spectroscopy (FT-IR), scanning electron microscope (SEM), energy dispersive spectrum analysis (EDX), X-Ray Fluorescence Spectrometer (XRF), and X Ray Diffraction analysis (XRD), which indicated that a significant amount of TiO 2 , SnO 2 , and Sb 2 O 3 were formed on the surface of Ti-Sn-Sb/γ-Al 2 O 3 particle electrode. It was also observed that the primary function of Ti-Sn-Sb/γ-Al 2 O 3 particle electrode in the three-dimensional electrode electrolysis process is the strong oxidizing function of ·OH for degrading OTC. Consequently, the analysis of degradation products of oxytetracycline (OTC) demonstrates. In addition, the results and conclusions of this study provide a methodological basis and engineering practice basis for removing the low concentration of antibiotics in water. Image 1 • Sodium alginate embedding method is used for preparing Ti-Sn-Sb/γ-Al 2 O 3 particle electrode. • Possible degradation mechanism of oxytetracycline is investigated and discussed. • Ti-Sn-Sb/γ-Al 2 O 3 particle electrode shows excellent electrocatalytic oxidation capacity. • It has positive significance for removing low concentration antibiotics in water. [ABSTRACT FROM AUTHOR]

Carboxylated chitosan (CPCTS) is used as substrates in the design and synthesis of CPCTS-based flocculants through UV-initiated polymerization techniques. The synthesized flocculants are applied to remove Cr and Ni ions from chromic acid lotion and electroplating wastewater through two-stage flocculation. This study investigates the effect of flocculant dosage, pH, reaction time, and stirring speed on the removal efficiency of Cr and Ni ions. Results indicated that the total Cr removal ratios by CPCTS-graft-polyacrylamide-co-sodium xanthate (CAC) and CPCTS-graft-poly [acrylamide-2-Acrylamido-2-methylpropane sulfonic acid] (CPCTS-g-P(AM-AMPS)) are 94.7% and 94.6%, respectively. The total Ni removal efficiencies by CAC and CPCTS-g-P(AM-AMPS) are 99.3% and 99.4%, respectively. The two-stage flocculation with CPCTS-based flocculants could reduce the total concentrations of Cr and Ni to 1.0 mg/L and 0.5 mg/L, respectively. The relationship of removal capacity and structural properties between the flocculants with different functional groups is established through Fourier transform infrared spectroscopy, nuclear magnetic resonance, scanning electron microscopy, and X-ray diffraction. The micro-interfacial behavior between the colloidal particles and the solution during the integrated chelation–flocculation are elucidated. Thus, CPCTS-based flocculants could be a potential material for the removal of high amounts of Cr and Ni ions in industrial wastewater. Image 1 • Chitosan based flocculants with xanthate and sulfonic acid group were designed and synthesized. • Flocculation process was used to treat industrial wastewater containing Cr and total Ni. • Rapid Removal and Separation of Cr and total Ni was obtained by CAC. • The micro-interfacial behavior during the integrated chelation–flocculation was elucidated. • Chitosan based flocculants showed an excellent potential capacity for removing heavy metals. [ABSTRACT FROM AUTHOR]