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It is of great importance to meet the need for clean and usable water in the world, which is one of the main priority issues of the European Foresight Platform action plan, and to improve and develop existing technologies in this regard. Membrane technology is one of the most used technologies in water treatment, which can be easily and economically modernized. In this study, we aimed to eliminate some disadvantages that affect the performance and cost of membranes, such as physical/chemical stability and contamination of the surface, by incorporating cyclodextrin derivatives (x-CDs, x: α,β,γ) functionalized reduced graphene oxide (rGO). Membrane performance studies such as contamination tests using water permeability, bovine serum albumin (BSA), flux, and arsenic (As) removal in the table-top pilot system were examined and compared for each composite membrane prepared at different rates. The results showed that the salt rejection values were ranked as Na 2 SO 4 > NaCl> MgSO 4 > MgCl 2 according to the salt type and it increased depending on the amount of substance. Besides, the arsenate removal studies were performed with the prepared membranes and it was observed that a maximum of 87.6% of the As was removed from the groundwater sample obtained from the Emet (Kütahya/Turkey) district. • New generation nanoporous polymeric composite membranes were prepared. • Cyclodextrins-functionalized reduced graphene oxide was incorporated into membranes. • The performance studies of membranes were examined in the table-top pilot system. • The salt rejection values were ranked as Na 2 SO 4 > NaCl > MgSO 4 > MgCl 2. • A maximum of 87.6% arsenate was removed from the groundwater sample. [ABSTRACT FROM AUTHOR]

The removal of some pollutants in the Sakarya River was investigated in this study. Sakarya River located in Turkey flows from the northeast of Afyonkarahisar City to the Black Sea. Nineteen different micropollutants including trihalomethanes (THMs), haloacetic acids (HAAs), endocrine disrupting compound (EDC) and pharmaceuticals personal care product (PPCP) groups, and water quality parameters such as dissolved organic carbon (DOC), ultraviolet absorbance at 254 nm wavelength (UV), hardness, and conductivity values were examined. To remove the micropollutants and improve the water quality, the treatment was performed with ozone, microfiltration (MF), and ultra-filtration (UF) membranes. The highest treatment efficiency was obtained with 1 mg/L ozone dosage and UP005 UF membrane. The trihalomethan formation potential (THMFP) and haloacetic acid formation potential (HAAFP) decreased with ozone + membrane at a concentration of 79 and 75%, respectively. After the treatment with ozone + membrane, the concentration of the micropollutants in the EDC and PPCP group remained below the detection limit. It was found that by using only membrane and only ozone, the maximum DOC removal efficiency achieved was 46 and 18%, respectively; and with ozone + membrane, this efficiency increased up to 82%. The results from the High-Pressure Size Exclusion Chromatography (HPSEC) analyses pointed that the substances with high molecular weight were converted into substances with low molecular weight after the treatment. The Fourier Transform Infrared (FTIR) analysis results showed that the aromatic and aliphatic functional groups in water changed after the treatment with ozone and that the peak values decreased more after the ozone + membrane treatment. [ABSTRACT FROM AUTHOR]

Abstract: The main objective of this work was to investigate the possibility of implementing a new hybrid system which combines reverse osmosis (RO) process with sorption-membrane filtration method. The RO tests were performed using a small-scale seawater reverse osmosis (SWRO) system which was established in Urla Bay, Izmir, Turkey. Dowex (XUS 43594.00) ion exchange resin with a particle size of 0–20μm was employed for removal of boron from RO permeates. A submerged-style hollow-fiber module containing two polypropylene membranes (diameter: 1.3mm, thickness: 200μm, pore diameter: 0.4μm) and a ZW-1 model submerged ultrafiltration module was used throughout the sorption-membrane filtration hybrid system. Sorption of boron was performed on a fine powdered boron selective ion exchange resin and boron loaded resin was separated by submerged membranes later on. The main advantage of sorption-membrane filtration hybrid process is the opportunity of using very fine particles of the resin, which increases specific surface and results in faster kinetics. Process variables such as resin concentration in the suspension, flow rates of fresh and saturated resins, and permeate have been evaluated in order to determine the efficiency of the hybrid process for boron removal from RO permeate. [Copyright &y& Elsevier]

Summary: In this study, the new sulphite sensitive ion-selective electrode(ISE) was prepared. The ISE was prepared from a combination of 5% perfluorooctanesulfonic acid(PFOS), 40% PVC and 55% dibutylphthalate(DBF).The sensitivity of the ISE to 1.0x10-7-1.0x10-1 M sulphite concentration was 58 ± 4 mV. Electrode sensitivity was characterized. The response time of this electrode is short and 30 s. The lifetime of ISE was approximately 210 days when used five times a day. It was determined that it can work at any pH value. It is not sensitive to anions and cations that may be present in the determination medium. The detection limit of the electrode a gainst the sulfide concentration was measured as 1.2x10-8 M. The amount of sulfites in dried apricots in Turkey, was measured with electrodes. Sulfite amount in dried apricot was determined as 2.328 ± 0.2417 mg/kg according to the average of 5 experiments and 95% confidence interval. The same sample was measured with DPP as 2.521 ± 0.2785.The validation of the obtained results in each case was proved by statistical "t" and "F" tests. [ABSTRACT FROM AUTHOR]