Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection

Permanent URI for this collectionhttps://hdl.handle.net/11147/7148

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  • Article
    Assessment of Heavy Metal Contamination and Removal Using <i>ceratophyllum Demersum</I> L.: a Case Study
    (inderscience Enterprises Ltd, 2024) Karaoglu, Aybike Gul; Gören, Ayşegül Yağmur; Kobya, Mehmet; Goren, Aysegul Yagmur; Mese, Esra; Tepe, Melike
    Assessment of heavy metal contamination in aquatic ecosystems continues to remain challenging. In this regard, Ceratophyllum demersum L. (C. demersum L.) is a common species found in rivers and can be used as a bioindicator to see the accumulation of heavy metals in the plant body. In this study, we aimed to investigate the accumulation of toxic metals and their effects on photosynthetic pigment content in plants for different seasons. The highest metal accumulations were observed in October 2019. The mean boron concentrations were 399 mg/kg in October 2019, while they were measured as 163 mg/kg in July 2020, most probably due to the decreasing agricultural activities in the studied area. However, the highest metal concentrations (aluminium 3,941 mg/kg and iron 5,161 mg/kg) were measured in July 2010. Moreover, the pigment content values were decreased with the increasing metal concentration in plants. The highest pigment content of 4.7 mu g/g was observed in October 2019, related to the low metal contamination in this season. Overall, C. demersum L. is a promising bioindicator of heavy metal pollution in water bodies with a significant amount of heavy metal accumulation capacity in a sustainable manner.
  • Review
    Citation - WoS: 16
    Citation - Scopus: 17
    Green Biohydrogen Production From Renewable Plant-Based Resources: a Comparative Evaluation
    (Institution of Chemical Engineers, 2024) Goren,A.Y.; Gören, Ayşegül Yağmur; Dincer,I.; Khalvati,A.
    Increasing energy demand drives the need for environmentally sustainable and economically viable renewable resources to eliminate problems related to greenhouse gas emissions. In recent years, research on biohydrogen (bio-H2) production as a renewable energy source has been recognized as a potential subject. It aims to reduce the pressures set by carbon dioxide emissions and the depletion of fossil fuel supplies. The field of bio-H2 science is considered potentially important; there have been increasing efforts to develop feasible systems for viable applications. This review further presents an updated and comprehensive review of bio-H2 production by dark fermentation (DF), photofermentation (PF), microbial electrolysis cells (MEC), and hybrid processes using plant-based materials. Among these processes, the highest H2 production yield of 680.8 mLH2/g-biomass was obtained using the DF-PF hybrid process. A comparison of bio-H2 production yields, the environmental impact, and the costs of DF, PF, MEC, and hybrid systems is considered, and superior performance was obtained for integrated biological processes. The comparative evaluation results showed that the MEC process is the most economical technology, followed by integrated systems. The PF is the most environmentally friendly H2 production process, presenting the lowest global warming potential (GWP) value of 1.88 kgCO2eq./kgH2 and acidification potential (AP) of 3,61 gSO2/kgH2 ; it is followed by DF and MEC processes. On the other hand, the highest GWP of 14.8 kgCO2eq./kgH2 and AP 103 gSO2/kg H2 were obtained for the DF-MEC process related to electrical and heat requirements during the production process. Furthermore, the WCP and WSF values were 84.5 and 3632.9 m3 for the DF-MEC integrated process due to the water utilization in anode and cathode solutions, while WCP was 2.91 m3 for the DF process. Overall, the results of this study further revealed that substantial effort, in the current and future, should be performed on bio-H2 production from plant-based biomass using integrated biological processes. Moreover, the bibliometric analysis presented that bio-H2 production from plant-based materials, MEC systems utilization, and nano-additives are growing areas in the bio-H2 research that provide zero-carbon energy in the future. © 2024 The Institution of Chemical Engineers
  • Book Part
    Arsenic Removal by Electrocoagulation
    (Wiley, 2022) Gören, Ayşegül Yağmur; Kobya, Mehmet
    Because of the toxic impacts on human health, the arsenic (As) limit value in drinking water was decreased from 50 to 10 ?g l-1 by the relevant authorities (WHO 1993; US EPA 2001). In this case, the problem of As pollution in natural water resources used for drinking water has grown even more and turned into a global crisis. According to reports in many parts of the world, over about 230 million people appear to be affected by high arsenic concentrations in groundwater. In this case, it turned out that there was a great need for cost-effective and environmentally friendly technologies from drinking water sources. One of the emerging water treatment technologies in recent years is electrocoagulation (EC) and it has been seen that it is effective in treating As (>99%) from water and eliminates some of the disadvantages of other conventional treatment processes. EC method includes electro-oxidation of anode electrode materials (iron and aluminum) and in situ production of coagulant agents. From groundwater resources with As content of 5-1000 ?g l-1, As removal efficiencies and operating costs (OCS) of EC technology using iron (Fe) and aluminum (Al) anodes were 85.0-99.9% and 0.0020-1.04 US$ m-3, respectively. Different types (plate, scrap, rod, and ball) of electrodes were used for As removal with the EC process, and it was observed that Fe electrodes or Fe-Al hybrid electrodes performed better in As removal. In addition, it has been determined that arsenate (As(V)) removal is more effective than arsenite (As(III)). A significant quantity of As(III) is oxidized in the EC process, resulting in precipitation, adsorption, and metal-oxy hydroxylic complex reactions. EC process has a lower OC to achieve As removal below the permissible WHO value compared to conventional treatment processes, accomplishing it as a further applicable option for As removal. © 2023 John Wiley & Sons, Inc.
  • Book Part
    Citation - Scopus: 32
    Language of Response Surface Methodology as an Experimental Strategy for Electrochemical Wastewater Treatment Process Optimization
    (Elsevier, 2022) Gören, Ayşegül Yağmur; Recepoğlu, Yaşar Kemal; Khataee, Alireza
    The availability and accessibility to safe and secure water resources are the key technological and scientific concerns of global significance. As a result of water scarcity worldwide, wastewater treatment and reuse are considered viable options to replace freshwater resources in agricultural irrigation and domestic and industrial purposes. A significant need for clean water has promoted the invention and/or enhancement of several electrochemical wastewater treatment (EWT) processes. Optimization of the process variables plays a crucial role in wastewater treatment to enhance technology performance, considering removal efficiency, operating cost, and environmental impacts. These processes are fundamentally complex multivariable, and the optimization through conventional methods is unreliable, inflexible, and time- and material-consuming. In this perspective, response surface methodology (RSM) appears to be a beneficial statistical experimental strategy for the performance optimization of the EWT process. This model could be utilized for the optimization and analysis of the individual and/or combined effects of operational variables on the treatment process to improve the system performance. Furthermore, this model provides a number of information from a slight number of experimental trials. In this chapter, a summary and a discussion are presented on the RSM model used in the electrochemical wastewater treatment processes to overcome process crucial challenges toward the optimization and modeling of process parameters. It provides a potential model to enhance the various types of wastewater treatment process performance with effective optimization. Overall, it is described that the RSM model can be used in EWT processes to find the optimum conditions.