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Öğe Characterization of littered face masks in the southeastern part of Turkey(Springer Heidelberg, 2021) Akarsu, Ceyhun; Madenli, Ozgecan; Deveci, Ece UmmuA possible source of microplastics has started to be released into nature because of the single-use face masks that protect us against the spread of COVID-19 and are being thrown onto the streets and into seas and nature. This study aims to estimate the amount of face mask use during the COVID-19 pandemic in Turkey, thereby expressing our concerns about waste management and plastic pollution and calling on appropriate solid waste management policies and governments to take the necessary measures to formulate their strategies at all levels. In this context, the number of masks in an area of 1 km(2) in 3 different cities was determined theoretically and experimentally. Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscope (SEM) were also used to evaluate plastic polymer characteristics of the single-use face mask. It was determined that the three cities produce roughly 10 tons of face masks in a day. With the increasing use of single-use plastics, the impact of face masks on microplastic pollution is of great concern. Although studies on the recovery of disposable masks continue, the level is insufficient. Therefore, studies to be carried out on technologies that will enable the repeated use of masks are important.Öğe Degradation of Recalcitrant Textile Dyes by Coupling Fungal and Photocatalytic Membrane Reactors(WILEY, 2016) Deveci, Ece Ummu; Dizge, Nadir; Yatmaz, Huseyin Cengiz; Tansel, BerrinWhite rot fungi have powerful and broad specific extracellular enzymatic systems and can degrade multiple types of recalcitrant compounds including azo dyes, therefore, they are used in the field of bioremediation. In the present study, decolorization and organic matter removal of Acid Red 88 (AR88) and Reactive Red 180 (RR180) dye solutions were performed using the white rot fungus Phanerochaete chrysosporium in a bioreactor. Degradation of the dyes was assessed using a hybrid process consisting of a fungal membrane bioreactor coupled with a photocatalytic membrane reactor. The photocatalytic oxidation step was conducted using the semiconductor ZnO as the catalyst with UVA irradiation. Experimental data with the fungal membrane bioreactor showed that the optimum pH was 4.5 for P. chrysosporium. Integrating photocatalytic step after the fungal membrane process improved the chemical oxygen demand (COD) removal efficiency up to 98 and 96% for RR180 and AR88 dye solutions, respectively. Color removal efficiencies after the photocatalytic degradation were 99.9% for both dye solutions.Öğe Development and validation of climate change awareness scale for high school students(Springer, 2023) Gonen, Cagdas; Deveci, Ece Ummu; Aydede, Meryem NurThe topic of climate change has begun to be referred to as the global climate change crisis. Despite the precautions taken through international accords, the main solution to climate change will be an increase in individual knowledge and awareness, as well as change in their behavior as a result. A valid and reliable climate change awareness (CCA) scale for high school students was developed in this study. As a scale development strategy, an inductive scale development approach was used. The study enrolled a total of 454 high school students. In this study, both exploratory and confirmatory factor analyses were used to provide validity. In this way, the CCA scale was developed and validated using two different randomly separated samples. Sample 1 (274 high school students) was assigned to the exploratory factor analysis group, while sample 2 (180 high school students) was utilized to confirm the factor structures via confirmative factor analysis. Confirmatory factor analysis was used to check model-data coherence and test assumptions about variable relationships. As a result of the study, a valid and reliable Likert-type scale for assessing high school students' climate change awareness was developed. The scale consists of 17 items and a Cronbach alpha value of 0.88. CFI (0.93), NFI (0.82), RFI (0.88) and GFI (0.90) RMSEA (0.045) have proven to be acceptable fit indexes between the model and the data for the research model. Thus, the fit indexes produced as a result of the CFA indicated that the model had good fit.Öğe Effective removal of hexavalent chromium by novel modified alginate-based biocomposites: Characterization, kinetics and equilibrium studies(Elsevier Sci Ltd, 2023) Madenli, Ozgecan; Akarsu, Ceyhun; Deveci, Ece UmmuThis study aims to synthesise novel biocomposites by combining fungal hyphae (Aspergillus oryzae or Penicillium roqueforti) and reduced graphene oxide to evaluate their adsorption potential for hexavalent chromium (Cr(VI)) from synthetic solutions and real wastewater. Fourier-transform infrared spectroscopy, scanning electron mi-croscopy, X-ray diffraction, and thermogravimetric analyses were used to characterize the effects of the carbon -based materials on microbial structure. In addition, independent variables including with a contact time (1-11 h), reduced graphene oxide concentration (0.1-1 g.L-1), and initial Cr(VI) concentration (10-50 mg L-1) were tested in batch-scale laboratory experiments by response surface methodology. Accordingly, maximum adsorp-tion was achieved at 11 h contact time, 1.0 g L-1 rGO, and 50 mg L-1 Cr(VI) with a removal rate of 98.9%. The pseudo-first-order and Freundlich isotherm models were well fitted. The results show that these biocomposites can serve as novel adsorbent for the removal of Cr(VI) from wastewater.Öğe Environmental sustainability of electricity generation: Case study of lignite combustion(Wiley, 2021) Atilgan Turkmen, Burcin; Deveci, Ece Ummu; Saglam, Cigdem SafakLignite is one of the most used Turkey's energy sources for electricity generation as there are large lignite reserves in the country. Lignite power plants are one of Turkey's main sources of GHG emissions. Therefore, understanding the environmental sustainability of generating electricity from lignite burning is essential for reducing environmental impacts. This research aims to assess the life cycle environmental impacts from a typical Turkish lignite power plant. In this paper, a system of the electricity from the lignite power plant is presented which covers all the life cycle stages-starting from the lignite mining up to the delivery of electricity to the grid. For this work to generate 1 kWh of generated is defined as the functional unit. The principal conclusion, to be drawn from this LCA of lignite power in Turkey, is that the majority of the emissions mostly originate from lignite burning to and lignite mining stages. The global warming potential associated with electricity generation from lignite power is estimated at 1,290 g CO(2)eq./kWh. The results obtained from this study provide a baseline for future scenarios to reduce the environmental impacts from the energy sector and to build a sustainable energy policy.Öğe Evaluation of biomass pretreatment to optimize process factors for different organic acids via Box-Behnken RSM method(Springer, 2021) Gonen, Cagdas; Deveci, Ece Ummu; Akter Onal, NagehanBiomass, as renewable energy source, is of importance to investigate to extend the conversion yield by microorganism. Because of lignocellulosic structure, biomass must be pretreated with a process, frequently inorganic acid has to be used with a problem of hazardous byproducts. Organic acid pretreatment is an efficient alternative to be investigated. Sugar beet pulp, as an agro-industrial residue of microorganism, can be utilized by pretreatment, which is usually a costly process. Pretreatment with organic acids creates a great opportunity to convert the process into more economic and effective. Moreover, pressure conditions significantly increase the yield of biodegradable sugar content. In this study, different organic acids of maleic, fumaric, oxalic, and acetic acid pretreatment was investigated to pretreatment of sugar beet pulp, which came vast amount from factories, under pressure and non-pressure conditions via Box-Behnken method to estimate optimum point of acid ratio (1, 3, 5%), time (10, 27.5, 45 min), and solid ratio factors (3, 6.5, 10%) for highest degradation. Results were also evaluated economically. As a result of the experiments, it was observed that acetic acid gave the best result with 409.16 g/L total sugar concentration than the other organic acids. The highest TS concentration of maleic, oxalic, and fumaric acid were 97.26, 97.85, and 91.37 g/L, respectively, under pressure. According to economical evaluation, owing to lower market price and highest TS formation yield, pretreatment cost of acetic acid pretreatment was found averagely 1.51 $/gTS under pressure conditions.Öğe Generic foresight model in changing hygiene habits with the pandemic: use of wet wipes in next generations(Springer, 2023) Koklu, Rabia; Ates, Asude; Deveci, Ece Ummu; Sivri, NuketThe vast use of wet wipes has now become a habitude, particularly following the altered perception of cleanliness during the pandemic and the encouragement towards using WW (wet wipe) to ensure parent's and children's hygiene. This study primarily aims to create a projection of the WW waste that will emerge in Turkey as a result of the promoted consumption by children who are predicted to retain the WW usage practices of their parents. In line with this habit adopted by children, the number of daily WW usage which is currently around 210 million is expected to rise to over 250 million between the years 2040 and 2060, depending on how the children are guided by their parent's existing habits. In this study, related calculations were made with FT-IR spectroscopy, taking into account the functional bond structure and percentage distribution of polymers in WWs. In this way, it is detected that 360 T, 568 T, and 623 T polymer materials would be thrown into the environment per day in 2021, 2040 and 2060, respectively. The damage of chemicals in WW content, employed at various concentrations, to the ecosystem structure is predicted and measures to be taken are outlined. [GRAPHICS] .Öğe Impact of COVID-19 restrictive precautions on air quality: case of Zonguldak, Turkey(Inderscience Enterprises Ltd, 2022) Koklu, Rabia; Turkmen, Burcin Atilgan; Deveci, Ece Ummu; Gonen, CagdasThe purpose of this study was to investigate and assess how restrictive COVID-19 precautions affect air quality in Zonguldak, as well as to determine the relationship between air quality and meteorological variables under these conditions. Daily PM2.5, PM10, SO2, and NOx concentrations and meteorological data, from 1 March to 31 May 2018, 2019, and 2020 were collected for this research. During the 2020 restrictive COVID-19 precautions, it was determined that concentrations of air pollutants were different and low based on the 95% confidence interval by using paired t-test samples. Meteorological variables were found to be similar to previous years, and the correlation between them and air pollutants was found to be significant (P < 0.01) but low according to Pearson correlations. As a result, meteorological variables were determined to have no direct effect on the low concentrations of air quality emissions during the 2020 pandemic. The overall findings revealed that anthropogenic impact has a negative impact on air quality and the air quality had improved during the COVID pandemic. Furthermore, the restriction on the region's coalmines during the COVID-19 pandemic has significant impact on the improvement of air quality.Öğe Integrated process of fungal membrane bioreactor and photocatalytic membrane reactor for the treatment of industrial textile wastewater(ELSEVIER SCIENCE BV, 2016) Deveci, Ece Ummu; Dizge, Nadir; Yatmaz, H. Cengiz; Aytepe, YasinIn this study, fungal membrane bioreactor (FMBR) and semiconductor photocatalytic membrane reactor (PMR) were used in order to test the efficiency of integrated fungal biodegradation and photocatalytic degradation of textile wastewater from reactive washing processes. It was found that color removal and chemical oxygen demand (COD) reduction efficiencies were 88% and 53% for photocatalytic degradation, respectively. TiO2 and ZnO were tested as semiconductor catalysts in the PMR and TiO2 showed better efficiencies than ZnO for both color and COD removal. However, it was attained that color removal and COD reduction efficiencies were about 56% and 60% for fungal biodegradation using Phatterochaete chrysosporium, respectively. Moreover, integrated system in which photocatalytic degradation was employed as a post-treatment application after fungal biodegradation process achieved high removal efficiencies for color and COD removal as 93% and 99%, respectively. (C) 2015 Elsevier B.V. All rights reserved.Öğe Investigation of the bacterial modified waste PET aggregate VIA Bacillus safensis to enhance the strength properties of mortars(Elsevier Sci Ltd, 2021) Akcaozoglu, Semiha; Adiguzel, Ali Osman; Akcaozoglu, Kubilay; Deveci, Ece Ummu; Gonen, CagdasPolyethylene terephthalates (PET), which are highly resistant to degradation under natural environmental conditions due to their inert, hydrophobic and high molecular weights, are collected in landfills or dispersed as waste. Considering the increasing use of PET, the interest in multidisciplinary studies aimed to obtaining high value added products from PET wastes has increased. In this study, the potential of using waste plastics made of Polyethylene terephthalate (PET) treated with bacteria as an aggregate in the production of mortar was investigated. First, the bacterial strains, which secreted esterase or cutinase, were screened for their ability to attach to hydrophobic surfaces and biofilm formation. TH401, which showed potential for the modification of the PET aggregates, was identified as Bacillus safensis. To enhance the compatibility of the PET, the waste PET aggregates were treated with submerged fermentation via B. safensis TH401. The FTIR analyses conducted after the treatment showed that the chemical structure of the PET had been modified. Mortar samples were prepared by using the modified PET aggregates. The compressive and flexural tensile strength values of the samples were measured on days 7, 28 and 56. The compressive strength values of the bacteria modified samples were 4.87%, 7.51% and 13.13% higher than the non-bacterial samples at 22 degrees C, 30 degrees C and 50 degrees C, respectively. The increase in curing temperatures had a positive effect on compressive and flexural tensile strength values. The highest strength values were obtained in the samples cured at 50 degrees C. In the EDX spot of the mixtures, major peaks of C, O, Ca were detected indicating the presence of CaCO3 and bacteria. Stratification on the PET surface as a result of bacterial modification was clearly observed in the SEM images. The test results showed that bacterial modification contributed to the increase in the strength of the waste PET aggregate concrete. It can be said that mortars produced with bacteria modified PET aggregates can be used as an economical and environmentally friendly material alternative in the construction industry. (C) 2020 Elsevier Ltd. All rights reserved.Öğe OPTIMIZATION OF CITRIC ACID PRODUCTION BY USING ASPERGILLUS NIGER ON CITRUS WASTE HYDROLYSATE IN COLUMN BIOREACTOR(Parlar Scientific Publications (P S P), 2017) Deveci, Ece Ummu; Ozyurt, MustafaAgro-industrial wastes such as fruit and vegetable peel constitute a major percentage in the content of wastewater and landfill. For this reason, investigating the conversion of value added products is very crucial. Citrus peel, which is an agro-industrial waste from citrus-processing industry (fruit slice and citrus juice), has a high potential in Turkey. The aim of this study is to demonstrate an alternative substrate combination for the fermentative production of citric acid and decrease the waste generation. In this study, the citrus peel used is obtained from citrus wastes cultivated at the Mediterranean Area of Turkey. Orange peel was derived from Washington navel orange (Citrus sinensis) type. Asp er gillus niger was used as a microorganism, and the hydrolysate obtained from orange residue and molasses were processed with pretreatment as substrates. Optimization was carried out in an aerobic column bio-reactor work-ing in a batch system. After citrus waste was hydrolysed with diluted acid and auto-clave obtain-ed, the hydrolysate had 85 g/L of total sugar concentration. The effects of process parameters such as aeration rate (vvm), initial pH, initial subs-trate concentrations (g/L), methanol ratio (w/v) and inoculum size (w/v) were analyzed and optimized. Within the optimum condition for the maximum production of citric acid, the amounts of the contents were: aeration rate-1 vvm, pH-6.0, substrate-140 g/L, methanol - 4%, inoculum - 3%. The production efficiency of citric acid was calcu-lated as 41.86%. These results, which demons-trate the viability of the citric acid production by column bioreactor from orange peel, could be of interest to possible future industrial applications.Öğe Optimization of sugar beet pulp pre-treatment with weak and strong acid under pressure and non-pressure conditions via RSM(Springer Heidelberg, 2023) Gonen, Cagdas; Onal, Nagehan Akter; Deveci, Ece UmmuBiofuels, derived from sustainable biomass feedstock, are promising alternatives for fossil derivative fuels to mitigate climate change and air pollution. The molecular structure of lignocellulosic biomass, which creates the limitation of utilization by microorganisms, can be degraded to fermentable sugar via a pre-treatment process. In this study, citric acid as a weak acid and sulfuric acid as a strong acid were used for the pre-treatment of sugar beet pulp under pressure and non-pressure conditions. Fermentable sugar amount was determined for total sugar and reduced sugar formation. Acid ratio, solid ratio and reaction time variables were optimized for the highest fermentable sugar concentration via Box-Behnken statistical methods. Finally, pressure is significantly increasing the strong acid effect, where the total sugar can reach up to 33 g/L at 4% acid ratio, 27.5-min reaction time, and 5% solid ratio. A 27.5-min reaction time gives 11 g/L total sugar concentration under pressure conditions at 5% citric acid ratio. The highest reduced sugar concentration is 1170 mg/L for sulfuric acid under pressure with only 3% solid ratio. SEM-EDX and FT-IR analysis show reliable degradation of molecular structure. SEM analysis showed that under the same conditions at 100 degrees C and 1 atm, sulfuric acid produced a much more intense deformation than citric acid, with more fragmentation occurring on the surface parallel to the TS. In addition, protein analysis obtained using Aspergillus niger in microbial cultivation experiments supports that pre-treatment products may be suitable for biofuel production and microbial use. The highest protein value obtained by sulfuric acid pre-treatment is 120 mg/L. Pre-treatment is necessary for the development of microbial activity in the production of biofuels from agricultural wastes. The total protein content is an important parameter in determining total enzyme production in monitoring microbial growth.Öğe Phosphate recovery from digestate using magnesium-modified fungal biochar(Springer, 2024) Surmeli, Recep Onder; Madenli, Ozgecan; Bayrakdar, Alper; Deveci, Ece Ummu; Calli, BarisMg-rich biochars have been used for the removal and recovery of phosphate (PO43-) and ammonium (NH4+) from waste streams. In this study, a novel magnesium-modified biochar (Mg-FBC) was synthesized by immobilizing waste magnesite dust (WMD) into Aspergillus niger fungal biomass for the adsorption of PO(4)(3- )and NH4+. Pyrolysis at various temperatures and analysis using techniques such as SEM-EDS, TGA, XRD, FTIR, and BET revealed that biochar produced at 650 degrees C (Mg-FBC650) exhibited enhanced surface properties favorable for effective adsorption. This improvement is attributed to the increased surface area facilitated by the hyphal structure of A. Niger and the effective dispersion of MgO on its surface. In experiments using a synthetic phosphate solution, the adsorption capacity reached 595 mg PO43-/g BC, fitting the Langmuir model at pH 9. In addition, experiments with the liquid fraction of a real digestate (LFD) showed adsorption capacities of 502 mg PO43-/g BC and 150 mg NH4+/g BC, respectively. The adsorption mechanism was elucidated through SEM-EDS, XRD, and FTIR analyses confirming that Mg-FBC650 facilitates a multifaceted adsorption mechanism, including adsorption, electrostatic attraction, chemical precipitation, and surface complexation. Consequently, PO43- was the primary adsorbate in the synthetic solution, while both PO43- and NH4+ were effectively removed from the LFD, indicating that Mg-FBC650 has substantial potential as an efficient adsorbent for nutrient removal. As a result, Mg-FBC650 is believed to hold significant potential as a slow-release and readily transferable bio-fertilizer, particularly suitable for application in soils deficient in organic matter, nitrogen, and phosphorus. [GRAPHICS] .Öğe Pre-treatment optimization of barley straw as agro-industrial waste via alkaline peroxide and ultrasound for soluble sugar production and degradation(Springer Heidelberg, 2021) Deveci, Ece Ummu; Gonen, Cagdas; Akarsu, CeyhunPre-treatment of biomass is of great importance to maximize the recovery of fermentable sugars and minimize the amount of enzyme inhibitors formed. There are several processes that can be applied for pre-treatment of agricultural industrial waste such as chemical, physical, physico-chemical, biological, and combined pre-treatments. Alkaline hydrogen peroxide (AHP) and ultrasonication are two of this pre-treatment process. The aim of this study was to investigate the pre-treatment performance of barley straw biomass using AHP and combined ultrasonic-hydrogen peroxide process via Box-Behnken design as a response surface methodology (RSM). The factors of time (30-120 min), particle size (0.2-1 mm), peroxide dosage (1-5%), and temperature (50-100 degrees C) are investigated for optimum operating conditions. For ultrasonication process, factors are time (5-30 min), particle size (0.2-1.0 mm) and US power (20-100 Kj/kgDM). During AHP pre-treatment, maximum total and reduced sugar concentration was found as 14 g/L and 660 mg/L, respectively, at maximum level of time and minimum level of dosage factors which are 120 min and 1%, respectively. Maximum total and reduced sugar concentration can be reached nearly 7.6 g/L and 810 mg/L, respectively, at minimum level of time which is 5 min and almost minimum level of chemical dosage in ultrasound-hydrogen peroxide process, respectively.Öğe Synthesis of graphite/rGO-modified fungal hyphae for chromium (VI) bioremediation process(Taylor & Francis Ltd, 2024) Madenli, Ozgecan; Akarsu, Ceyhun; Adiguzel, Ali Osman; Altuntepe, Ali; Zan, Recep; Deveci, Ece UmmuBioremediation is a promising technology that can eliminate the drawbacks of conventional treatment methods in removing harmful toxic metals including chromium(VI). Therefore, in this study, fungal hyphae modified with graphite and reduced graphene oxide were synthesized and assessed for their potential to bioremediate heavy metals for the first time in the literature. The effects of the carbon-based materials on microbial structure were characterized using scanning electron microscopy analysis. Thermogravimetric, RAMAN, X-ray diffraction, and enzymatic analyzes were performed to determine the role of functional groups. In addition, batch adsorption experiments utilizing response surface methodology were conducted to optimize operating parameters such as time (1-11 h), chromium (10-50 mg/L), and graphite/reduced graphene oxide (0.1-1 g/L). The maximum adsorption capacity with the graphene fungal hyphae was determined to be 568 mg.g(-1), which is 9.7 times that of the crude fungal hyphae. The Cr(VI) removal for fungal hyphae-graphite and fungal hyphae-reduced graphene oxide biocomposites was 98.25% and 98.49%, respectively. The isothermal and kinetic results perfectly matched the 2nd order pseudo-model and Langmuir model in terms of the nature of the adsorption process. The laboratory scale test results indicate that fungal hyphae modified with graphite and reduced graphene oxide have a high adsorption capacity, suitable for the removal of chromium (VI) from wastewater.Öğe Synthesis, characterization, and phosphorus adsorption of Mg/Fe-modified biochar from cotton stalk pretreated with Coriolus versicolor(Wiley, 2024) Deveci, Ece Ummu; Oz, Derya; Madenli, OzgecanIn recent years, the research potential in utilizing biochars as adsorbents in adsorption processes has grown due to their eco-friendly and economical nature. However, biochar often possesses a negative surface charge that limits its affinity for binding anions. Nitric acid washing and pretreatment with Coriolus versicolor can break down the lignocellulosic structure in cotton stalk waste, facilitating the subsequent impregnation of Mg and Fe metal oxides. These pretreatment steps can lead to the production of diverse and functionalized biochars with higher adsorption capacities. In this study, cotton stalk waste was first washed with diluted nitric acid and then subjected to biological pretreatment by incubation with C. versicolor, followed by impregnation with Mg and Fe to obtain CV-CS/Fe and CV-CS/Mg biochars. The results showed that the applied pretreatments altered the physicochemical properties and significantly increased the phosphorus adsorption capacity. The adsorption capacities of CV-CS/Fe and CV-CS/Mg biochars were found to be 277.88 and 507.01 mg g(-1), respectively. The results indicate that the incorporation of multiple metal oxide impregnates enhances P adsorption. Furthermore, in the kinetic study, pseudo-first-order and pseudo-second-order models provided a well fit, determining chemical adsorption as the main adsorption mechanism for phosphorus adsorption. The biochars demonstrated compatibility with Langmuir-Freundlich models. Overall, the findings suggest the possibility of synthesizing biochars with improved adsorptive properties through pretreatment, and these engineered biochars hold promising potential as effective adsorbents in the field.Öğe Treatment of slaughterhouse wastewater by electrocoagulation and electroflotation as a combined process: process optimization through response surface methodology(Springer Heidelberg, 2021) Akarsu, Ceyhun; Deveci, Ece Ummu; Gonen, Cagdas; Madenli, OzgecanThe contamination of water with organic compounds has become an increasing concern in today's world. The cost-effective and sustainable treatment of industrial wastewaters is a major challenge. Advanced treatment techniques such as electrocoagulation-electroflotation offer economic and reliable solutions for the treatment of industrial wastewater. In this study, the electrocoagulation-electroflotation method was investigated for the simultaneous removal of chemical oxygen demand, total phosphorus, total Kjeldahl nitrogen, and color via response surface methodology. Factors such as electrode combination (Fe and Al), current density (10-20 mA/cm(2)), pH (3.0-9.0), and electrode distance (1-3 cm) were investigated in the treatment of wastewater to obtain maximum treatment efficiency. It was determined that chemical oxygen demand, total Kjeldahl nitrogen, total phosphorus, and color removal reached up to 94.0%, 77.5%, 97.0%, and 99.0%, respectively. Treatment costs were found as $0.71 with the Al-Fe electrode combination.
