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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, the efficiency of conventional drinking water treatment processes (coagulation-flocculation and chlorination) for endosulfan removal and metabolite formation were investigated. Taguchi experimental design and analysis of variance (ANOVA) were applied using Minitab program. The highest removal efficiency was obtained as 65% at 6 mg/L initial endosulfan concentration, 30 mg/L aluminium sulfate dose and pH 7, in the coagulation-flocculation experiments. In chlorination experiments, it was determined that the variables of initial endosulfan concentration, chlorine dose, pH and contact time contributed 55.84%, 21.25%, 5.74% and 3.48% to the endosulfan removal, respectively, according to the ANOVA results. The presence of endosulfan metabolites like endosulfan ether, sulfate, and lactone were also detected and measured. P values were obtained only in endosulfan sulfate formation as a result of chlorination, lower than 0.05 for initial endosulfan concentration, chlorine dose and time parameters; apart from this, P values were not statistically significant in all other experiments. [ABSTRACT FROM AUTHOR]

In this study the magnetic nanocomposite material was synthesized with Fe3O4 impregnated to sugar beet pulp using chemical precipitation technique. Ni(II) removal performance of magnetic nanocomposite was investigated under different environmental conditions such as contact time, adsorbent dose, pH, initial heavy metal concentration, etc. The experimental studies have shown that, 81.2% Ni(II) removal efficiency was achieved at optimal conditions (25 mg/L initial Ni(II) concentration at 40 minute contact time, 200 rpm shaking speed, 5 g/L nanocomposite dose and pH 6.6). Freundlich and Langmuir isotherm experiments were performed and correlation coefficients were determined as 94.5% and 99.4%, respectively. The maximum adsorption capacity of material was achieved as 9.36 mg/g. These findings indicate that the adsorption that takes place is a monolayer process. The results of the pseudo-second order kinetic model (R2 = 0.9947) indicate the chemisorptions process is used for Ni(II) removal using the electrostatic interaction. Thermodynamic studies illustrated that Ni(II) adsorption onto nanocomposite are exothermic and causes a decrease in the entropy. The adsorption of Ni(II) ions is non-spontaneous except for at low temperature and low initial concentrations. Nanocomposite characterization was illuminated with XRD, FT-IR, BET, TGA, TEM, SEM/EDX analysis. In this study, it was aimed to synthesis new adsorbent using sugar beet pulp together with Fe3O4 under suitable conditions, obtain a magnetic nanocomposite, and examine the reusability and recovery properties of the produced material. The use of industrial wastes as an adsorbent material provides both a solution to the problem of the removal of wastes and a reuse method for the use of wastes as a low cost adsorbent for a useful purpose. Therefore, it has two advantages: There is a need to investigate the feasibility of investigating all possible industry-based cheap adsorbent sources as well as the removal of heavy metals for the production of a reliable and harmless adsorbent. [ABSTRACT FROM AUTHOR]

In this study, the removal efficiency of reactive red 195 (RR195) dye by photocatalysis process under UV-A and visible irradiation using Ag/TiO2 and Ag/TiO2/Fe3O4 nanocomposite was investigated. The structural properties of the photocatalyst were evaluated using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscope-energy dispersive X-ray (SEM–EDX), and transmission electron microscope (TEM) analyses. The effects of irradiation time, initial dye concentration, light power, solution initial pH, and ultrasound application on RR195 removal by photocatalysis process were determined experimentally. Ninety-two and 95% dye removal efficiencies were obtained using Ag/TiO2/Fe3O4 photocatalyst, after 30 min of UV-A irradiation for photocatalysis and sonophotocatalysis processes, respectively. The removal of RR195 dye under visible irradiation for 120 min using magnetic nanocomposite was determined as 92% and 96% for photocatalysis and sonophotocatalysis processes, respectively. The percentage of RR195 removal under UV-A and visible light decreased with the increase in initial dye concentration and pH values and increased with the increase in light power. In photocatalysis experiments, the highest dye removal was obtained as 98% and 96% for 120 min visible irradiation and 30 min UV-A irradiation, respectively, under optimum initial conditions (pH: 3, Ag/TiO2/Fe3O4 dose: 0.1 g/L, dye concentration: 25 mg/L, and light power: 27 W). [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]

In this study the magnetic nanocomposite material was synthesized with Fe 3 O 4 impregnated to sugar beet pulp using chemical precipitation technique. Ni(II) removal performance of magnetic nanocomposite was investigated under different environmental conditions such as contact time, adsorbent dose, pH, initial heavy metal concentration, etc. The experimental studies have shown that, 81.2% Ni(II) removal efficiency was achieved at optimal conditions (25 mg/L initial Ni(II) concentration at 40 minute contact time, 200 rpm shaking speed, 5 g/L nanocomposite dose and pH 6.6). Freundlich and Langmuir isotherm experiments were performed and correlation coefficients were determined as 94.5% and 99.4%, respectively. The maximum adsorption capacity of material was achieved as 9.36 mg/g. These findings indicate that the adsorption that takes place is a monolayer process. The results of the pseudo-second order kinetic model (R 2 = 0.9947) indicate the chemisorptions process is used for Ni(II) removal using the electrostatic interaction. Thermodynamic studies illustrated that Ni(II) adsorption onto nanocomposite are exothermic and causes a decrease in the entropy. The adsorption of Ni(II) ions is non-spontaneous except for at low temperature and low initial concentrations. Nanocomposite characterization was illuminated with XRD, FT-IR, BET, TGA, TEM, SEM/EDX analysis.