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In this study, the efficiency of the synthesised Ag/TiO2/Fe3O4 catalyst in the removal of endosulfan and metabolite formation by the photocatalysis process, the effect, and optimisation of the ambient conditions were investigated under UV–C light source. Photocatalysis process for endosulfan removal and degradation to metabolites was optimised with Taguchi experimental design method and the results were evaluated statistically by analysis of variance. Light intensity, amount of catalyst, initial endosulfan concentration, pH, and time were chosen as controllable parameters. The highest S/N ratios on the based on parameters were obtained at 27 W light power, pH 4, 0.5 g/L catalyst amount, 60 min reaction time and 4 mg/L initial endosulfan concentration. Since these values, at which the highest removal rate will be achieved, were not found in the experimental design, a confirmation experiment was performed and the removal was obtained as 93.2%. It was found that the most effective parameters on the removal efficiency were the initial endosulfan concentration and pH, respectively. As a result of analysis of variance, Fcritical values showed that the effects of light power, catalyst amount and reaction time on endosulfan removal were not statistically significant. When the P values are examined, it is seen that there is a significant difference between the initial endosulfan concentration and the levels of the pH factor for endosulfan removal. No formations of endosulfan sulphate, endosulfan ether, and endosulfan lactone were observed at high concentrations while endosulfan was removed. [ABSTRACT FROM AUTHOR]

In this study, photochemical deposition and co-precipitation methods were used to synthesise Ag/TiO2 and magnetic Ag/TiO2/Fe3O4 photocatalysts, respectively. The physical and chemical properties of the Ag/TiO2 and Ag/TiO2/Fe3O4 photocatalysts were characterised by X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and Fourier Transform Infrared Spectroscopy (FT-IR) analyses. The synthesised photocatalysts were used to remove Reactive Red 195 (RR195) dye the most commonly used in the textile industry. The photocatalytic and sonophotocatalytic removal was investigated using different light types such as UV-A and visible light. In the optimum conditions (UV-A and visible light intensity 27 W, 25 mg/L initial RR195 concentration, pH 6 ve 0.1 g/L catalyst dose) of photocatalysis, the photodegradation of magnetic Ag/TiO2/Fe3O4 was found 72% at 120 min irradiation of visible light but the degradation was 65% at 30 min irradiation of UV-A light. While in case of the sonophotocatalysis, the degradation of magnetic Ag/TiO2/Fe3O4 was found 85% at 120 min irradiation of visible light but the degradation was 85% at 30 min irradiation of UV-A light. [ABSTRACT FROM AUTHOR]

In this study, a magnetic new nanocomposite was synthesised using an agricultural waste (peanut hull), iron (II) sulphate and iron (III) chloride by co-precipitation method. The structure of magnetic nanocomposite was illuminated with Scanning Electron Microscopy, Fourier Transform Infrared Spectroscopy, X-ray Diffraction Spectroscopy techniques; thermogravimetric and Brunauer-Emmett-Wires analysis. Effects of different ambient conditions such as contact time, pH, adsorbent dose and initial nickel concentration on removal of nickel ions were investigated. 82.8% nickel removal efficiency was achieved for 200 mL reactor volume including 10 mg/L initial nickel concentration at 25°C constant ambient temperature. According to the results of batch experiments, second-order kinetic model and Langmuir isotherm model was found to be compatible with datas. Nickel removal using magnetic nanoparticle synthesised with agricultural waste is a promising method because of low cost, separation simplicity and efficiency adsorbent. [ABSTRACT FROM AUTHOR]