PubMed İndeksli Yayınlar Koleksiyonu / PubMed Indexed Publications Collection

Permanent URI for this collectionhttps://hdl.handle.net/11147/7645

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Now showing 1 - 6 of 6
  • Article
    Citation - WoS: 12
    Citation - Scopus: 14
    Identifying Geogenic and Anthropogenic Aluminum Pollution on Different Spatial Distributions and Removal of Natural Waters and Soil in Çanakkale, Turkey
    (Amer Chemical Soc, 2023) Hızlı, Sezin; Koraoğlu, Aybike Gül; Gören, Ayşegül Yağmur; Kobya, Mehmet
    The Canakkale-Kirazli region (Turkey) is enriched with minerals, especially aluminum (Al), which dangerously get transported into aquatic media due to several mining and geological activities in recent years. In this study, Al and other potentially toxic metals (PTMs) including B, Ba, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Si, and Zn, in both water and soil samples, were measured for quality determination. Selected metals were also analyzed by the enrichment factor (EF), the geoaccumulation index (I-geo), the contamination factor (CF), and the pollution load index (PLI) to evaluate both water and soil pollution geogenically or anthropogenically. Also, the metals were clustered to support the pollution source with Pearson's correlation, principal component analysis (PCA), and hierarchical cluster analysis (HCA). Forty-five natural water samples and 12 soil samples were collected spatially. To perform pollution assessment, two fundamental treatment processes to remove Al pollution from the sample including the highest Al concentration (38.38 mg/L) in water were applied: (1) precipitation with pH adjustment and (2) removal with ion exchange. The pH values of water samples were changed in the range of 3-9 to test the dissolution of Al. The results demonstrated that the study area was mostly under the influence of geogenic aluminum pollution.
  • Article
    Citation - WoS: 13
    Citation - Scopus: 13
    Countrywide Spatial Variation of Potentially Toxic Element Contamination in Soils of Turkey and Assessment of Population Health Risks for Nondietary Ingestion
    (American Chemical Society, 2022) Gören, Ayşegül Yağmur; Genişoğlu, Mesut; Kazancı, Yiğithan; Sofuoğlu, Sait Cemil
    Countrywide surface soil concentrations of potentially toxic elements (PTEs) in Turkey were reviewed in the Web of Science database. A total of 93 papers were investigated to compose a PTE dataset for determining spatial variations and estimating exposure and health risks. Al, As, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, and Zn were selected as PTEs in surface soil. A compiled PTE concentration dataset was used to estimate chronic toxic risks (CTRs) and carcinogenic risks (CRs) according to the deterministic and probabilistic approaches. While the CTR and CR levels of age and sex groups were estimated using a deterministic approach, population risks were estimated using a probabilistic approach. CTR and CR levels in lower age groups and female sex groups were estimated to be higher than those in higher age groups and associated male sex groups. The average CTR levels of the nondietary ingestion of As-containing soil in <11 year age groups were near/just above the threshold level, while As-associated average CR levels of adults and other age groups were estimated to be in the acceptable risk range (10-6 < CR < 10-5) and low priority risk range (10-5 < CR < 10-4), respectively. As-, Cr(VI)-, and Pb-associated upper-bound CR levels of the Turkish population were simulated to be 5.14 × 10-4, 6.23 × 10-5, and 2.34 × 10-6, respectively. Health risk models show the significance of As in both chronic toxic and carcinogenic effects.
  • Article
    Citation - WoS: 31
    Citation - Scopus: 35
    Electrochemical 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 Eser
    In 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: 33
    Citation - Scopus: 37
    Energy Production From Treatment of Industrial Wastewater and Boron Removal in Aqueous Solutions Using Microbial Desalination Cell
    (Elsevier, 2021) Gören, Ayşegül Yağmur; Ökten, Hatice Eser
    As a result of a much needed paradigm shift worldwide, treated saline water is being considered as a viable option for replacing freshwater resources in agricultural irrigation. Vastly produced geothermal brine in Turkey may pose a significant environmental risk due to its high ionic strength, specifically due to boron. Boron species, which are generally found uncharged in natural waters, are costly to remove using high-throughput membrane technologies such as reverse osmosis. Recent advances in bioelectrochemical systems (BES) has facilitated development of energetically self-sufficient wastewater treatment and desalination. In this study, removal of boron from synthetic solutions and real geothermal waters, along with simultaneous energy production, using the microbial desalination cell (MDC) were investigated. Optimization studies were conducted by varying boron concentrations (5, 10, and 20 mg L-1), air flow rates (0, 1, and 2 L min(-1)), electrode areas (18, 24, 36, and 72 cm(2)), catholyte solutions, and operating modes. Even though the highest concentration decrease was observed for 20 mg-B L-1, 5 mg-B L-1 concentration experiment gave the closest result to the 2.4 mg-B L-1 limit value asserted by WHO. Effect of electrode surface area was proven to be significant on boron removal efficiency. Employing the optimum conditions acquired with synthetic solutions, boron and COD removal efficiencies from real geothermal brine were 44.3% and 90.6%, respectively. MDC, being in its early levels of technology readiness, produced promising desalination and energy production results in removal of boron from geothermal brine.
  • Article
    Citation - WoS: 22
    Citation - Scopus: 25
    Novel Hybrid Treatments of Textile Wastewater by Membrane Oxidation Reactor: Performance Investigations, Optimizations and Efficiency Comparisons
    (Elsevier, 2019) Aydıner, Coşkun; Mert, Berna Kiril; Doğan, Esra Can; Yatmaz, Hüseyin Cengiz; Dağlı, Sönmez; Aksu, Şeyda; Gören, Ayşegül Yağmur; Balcı, Esin
    Feasible reclamation of industrial wastewaters by consuming less resource and time requires researchers to develop advanced and sophisticated solutions to meet today's versatile needs. In this respect, novel technological applications of hybrid membrane oxidation reactor (MOR) comprising of the Fenton or photo-Fenton enhanced ultrafiltration (FEUF and pFEUF), was demonstrated for treating textile washing wastewater. Their comparative hybrid performances were explored based on response surface analyses of Taguchi experimental designs that were optimized for maximized responses at minimum oxidant and acid consumptions. From eleven specific variables, those affecting the hybrid treatment performances at significant levels were found as H2O2 amount, process time, membrane type, Fe2+ concentration and temperature. The pFEUF treatment showed better and faster organics removal efficiency than by FEUF, and the UF process was seen to be more affected from changing operational conditions in pFEUF. Organic pollutants were oxidized by 56.6 +/- 8.7% degradation and 31.5 +/- 3.2% mineralization, while UF allowed a synergistic contribution to the hybrid MOR performance by 38.1 +/- 4.7% and 17.3 +/- 3.1%, respectively. Compared to simultaneous MOR and external UF after Fenton, sequential MOR was found as the best solution by an efficiency of 84.5% COD, 70.5% TOC, and 155.6 L/m(2).h. The effluents could be readily produced with quality suitable for directly discharging to the sewage infrastructure system resulting in a complete treatment. This study proved that the developed MOR techniques are technologically favorable for the treatment of industrial organic wastewaters due to high treatment performances and less resource, time and land needs. It can be finally declared that they can be used as rather attractive solutions for not only wastewater reclamation but also water recovery by further handling of their effluents. (C) 2019 Elsevier B.V. All rights reserved.
  • Article
    Citation - WoS: 37
    Citation - Scopus: 40
    Arsenite Removal From Groundwater by Aerated Electrocoagulation Reactor With Al Ball Electrodes: Human Health Risk Assessment
    (Elsevier, 2020) Gören, Ayşegül Yağmur; Kobya, Mehmet; Öncel, Mehmet Salim
    The application of conventional electrocoagulation (EC) process for removal of As(III) from groundwater suffers from the need of external oxidation agent for oxidation of As(III) to As(V). To tackle this limitation, an aerated EC reactor for the removal of As(III) from groundwater was evaluated in this study. The effect of initial pH(i), air flow rate, applied current, and electrode height in the EC reactor was examined. The experimental results showed that removal of arsenic mostly dependent on the applied current, electrode height in EC reactor, and air flow rate. The As(III) removal efficiency (99.2%) was maximum at pH(i) of 7.5, air flow rate of 6 L min(-1), applied current of 0.30 A, and electrode height in EC reactor of 5 cm, with an total operating cost of 0.583 $ m(-3). Furthermore, the carcinogenic risk (CR) and non-carcinogenic risk of arsenic (As) was in the range of tolerable limits at all operating conditions except applied current of 0.075 A at the end of the aerated EC process to remove As from groundwater. The present EC reactor process is able to remove As(III) from groundwater to below 10 mu g L-1, which is maximum contaminant level of arsenic in drinking water according to the World Health Organization (WHO). (C) 2020 Elsevier Ltd. All rights reserved.