Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7148
Browse
6 results
Search Results
Now showing 1 - 6 of 6
Article Citation - WoS: 31Citation - Scopus: 35Electrochemical Degradation of Methylene Blue by a Flexible Graphite Electrode: Techno-Economic Evaluation(American Chemical Society, 2022) Gören, Ayşegül Yağmur; Recepoğlu, Yaşar Kemal; Edebali, Özge; Şahin, Çağrı; Genişoğlu, Mesut; Ökten, Hatice EserIn this study, electrochemical removal of methylene blue (MB) from water using commercially available and low-cost flexible graphite was investigated. The operating conditions such as initial dye concentration, initial solution pH, electrolyte dose, electrical potential, and operating time were investigated. The Box-Behnken experimental design (BBD) was used to optimize the system's performance with the minimum number of tests possible, as well as to examine the independent variables' impact on the removal efficiency, energy consumption, operating cost, and effluent MB concentration. The electrical potential and electrolyte dosage both improved the MB removal efficiency, since increased electrical potential facilitated production of oxidizing agents and increase in electrolyte dosage translated into an increase in electrical current transfer. As expected, MB removal efficiency increased with longer operational periods. The combined effects of operating time-electrical potential and electrical potential-electrolyte concentration improved the MB removal efficiency. The maximum removal efficiency (99.9%) and lowest operating cost (0.012 $/m3) were obtained for initial pH 4, initial MB concentration 26.5 mg/L, electrolyte concentration 0.6 g/L, electrical potential 3 V, and operating time 30 min. The reaction kinetics was maximum for pH 5, and as the pH increased the reaction rates decreased. Consequent techno-economic assessment showed that electrochemical removal of MB using low-cost and versatile flexible graphite had a competitive advantage.Article Citation - WoS: 31Citation - Scopus: 33Enhanced Bactericidal and Photocatalytic Activities of Zno Nanostructures by Changing the Cooling Route(Royal Society of Chemistry, 2018) Horzum, Nesrin; Hilal, Mohamed Elhousseini; Işık, TuğbaWe report on a simple synthesis of ZnO nanowires by calcination of zinc acetate. The effect of calcination temperature and cooling route on the antibacterial and photocatalytic properties is demonstrated by varying the size and surface area of the nanowires. The decrease of the calcination temperature followed by a rapid cooling procedure leads to a smaller size and larger surface area of the nanowires. ZnO nanowires are found to be effective against the growth of E. coli at the microgram level. In addition, the photocatalytic activity of the synthesized ZnO nanowires is demonstrated by the successful degradation of the organic dye methylene blue.Article Citation - WoS: 1Citation - Scopus: 1Flexible Pvc-Silica Composites as an Adsorptive Material for Water Soluble Dyes(Smithers Rapra Technology, 2013) Ulutan, Sevgi; Yetgin, Senem; Balköse, DevrimMethylene Blue (MB) adsorption studies were performed on flexible Polyvinyl Chloride/Silica composites which were obtained by using plastisol-plastigel technology. Change of MB concentration in aqueous phase as the adsorption process advanced was followed by using visible spectroscopy. The diffusion of MB through the composites exhibited non-Fickian behavior with a diffusivity of 10-11 m2s-1. Making use of such PVC-silica composite sheets as column packing, the packing time will be reduced and the surface available for diffusion will be increased. © 2013 Smithers Rapra Technology.Article Citation - WoS: 21Citation - Scopus: 23Adsorption of Methylene Blue From Aqueous Solution on High Lime Fly Ash: Kinetic, Equilibrium, and Thermodynamic Studies(Taylor and Francis Ltd., 2012) Keleşoğlu, Serkan; Kes, Mürşide; Sütçü, Leman; Polat, HürriyetKinetic, equilibrium, and thermodynamic studies were performed for the batch adsorption of methylene blue (MB) on the high lime fly ash as a low cost adsorbent material. The studied operating variables were adsorbent amount, contact time, dye concentration, and temperature. The kinetic data were analyzed using the pseudo-first order and pseudo-second order kinetic models and the adsorption kinetic was followed well by the pseudo-second order kinetic model. The equilibrium data were fitted with the Freundlich, Langmuir, and Dubinin Radushkevich (D-R) isotherms and the equilibrium data were found to be well represented by the Freundlich and D-R isotherms. Based on these two isotherms MB is taken by chemical ion exchange and active sites on the high lime fly ash have different affinities to MB molecules. Various thermodynamic parameters such as enthalpy of adsorption (ΔH°), free energy change (ΔG°), and entropy change (ΔS°) were investigated. The positive value of ΔH° and negative value of ΔG° indicate that the adsorption is endothermic and spontaneous. The positive value of ΔS° shows the increased randomness at the solid-liquid interface during the adsorption. A single-stage batch adsorber was also designed based on the Freundlich isotherm for the removal of MB by the high lime fly ash. © 2012 Copyright Taylor and Francis Group, LLC.Article Citation - WoS: 45Citation - Scopus: 55Incorporation of Iron Nanoparticles Into Clinoptilolite and Its Application for the Removal of Cationic and Anionic Dyes(Korean Society of Industrial Engineering Chemistry, 2015) Nairat, Muath; Shahwan, Talal; Eroğlu, Ahmet Emin; Fuchs, HaraldThis study reports the preparation of composite sorbents of iron nanoparticles (nZVI) and clinoptilolite at various iron/clinoptilolite ratios. The composites were characterized using various characterization techniques. The material was used for the removal of methylene blue (MB) and methyl orange (MO) as model cationic and anionic dyes. The experiments investigated the effects of time, loading, initial pH, reusability, and temperature on the removal process. According to the results, Cl-nZVI showed fast and quantitative removal over a wide range of concentrations. The removal process was endothermic in nature, and the composite demonstrated reusability for several trials.Article Citation - WoS: 654Citation - Scopus: 786Green Synthesis of Iron Nanoparticles and Their Application as a Fenton-Like Catalyst for the Degradation of Aqueous Cationic and Anionic Dyes(Elsevier Ltd., 2011) Shahwan, Talal; Abu-Sirriah, Sadieh; Nairat, Muath; Boyacı, Ezel; Eroğlu, Ahmet Emin; Scott, Thomas B.; Hallam, Keith R.Iron nanoparticles were produced using extracts of green tea leaves (GT-Fe NPs). The materials were characterized using TEM, SEM/EDX, XPS, XRD, and FTIR techniques and were shown to contain mainly iron oxide and iron oxohydroxide. The obtained nanoparticles were then utilized as a Fenton-like catalyst for decolorization of aqueous solutions containing methylene blue (MB) and methyl orange (MO) dyes. The related experiments investigated the removal kinetics and the effect of concentration for both MB and MO. The concentrations of dyes in aqueous solution were monitored using ultraviolet–visible (UV–vis) spectroscopy. The results indicated fast removal of the dyes with the kinetic data of MB following a second order removal rate, while those of MO were closer to a first order removal rate. The loading experiments indicated almost complete removal of both dyes from water over a wide range of concentration, 10–200 mg L−1. Compared with iron nanoparticles produced by borohydride reduction, GT-Fe nanoparticles demonstrated more effective capability as a Fenton-like catalyst, both in terms of kinetics and percentage removal.