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Öğe Adsorptive separation of adipic acid from aqueous solutions by perlite or its composites by manganese or copper(Techno-Press, 2014) Uslu, Hasan; Demir, Goksel; Bayat, Cuma; Wasewar, Kailas L.; Bamufleh, Hisham S.Adipic acid (hexane-1,6-dioic acid) is one of the most used chemical in industrial applications. This must be separated from any environmental contaminant. In this study, adipic acid separation from wastewater by adsorption method onto Perlite or Perlite + Mn or Perlite + Cu composites was investigated. Adsorption of Adipic acid was investigated in terms of equilibrium, and thermodynamic conditions. For thermodynamic investigations the experiments carried out at three different temperatures (298 K, 318 K, 328 K). In the equilibrium studies, 2 g of perlite and its composites were determined as the optimal adsorbent amount. Freundlich and Langmuir isotherms were applied to the experimental data. Freundlich isotherms for all temperatures used in this work gave some deviations with R square values under 0.98 where as Langmuir isotherm gave good results with R square values upper 0.99 at different temperatures. As a result of thermodynamic studies, adsorption enthalpy (Delta H), adsorption entropy (Delta S), and adsorption free energy (Delta G) have been calculated for each adsorbents.Öğe Heavy metal amounts in soil and sediments of surface water sources in the industrial regions of Istanbul(Destech Publications, Inc, 2007) Ozbas, Emine Elmaslar; Ozcan, H. Kurtulus; Balkaya, Nilgun; Demir, Goksel; Bayat, CumaToday, heavy metal-oriented soil pollution composes a substantial problem, especially in regions with dense industrial activities. Industrial wastes may also be introduced to superficial waters either directly or indirectly, forming a dense accumulation of heavy metal in aquatic sediments. Istanbul exhibits a high density of industrial activities. In this study, soil and sediment samples were taken from 4 superficial water resources in the dense industrial region that borders Istanbul. In the first section of the study, the heavy metal concentrations (Cu, Ni, Zn, Pb, Cd) in these samples were determined and compared with each other. In the second section of the study, after the comparison with similar studies in the literature, an assessment was made.Öğe Heavy metal concentrations of atmospheric ambient deposition dust in Istanbul-Bosphorus Bridge tollhouses(Destech Publications, Inc, 2007) Ozcan, H. Kurtulus; Demir, Goksel; Nemlioglu, Semih; Sezgin, Naim; Bayat, CumaAir Pollution emissions due to motor vehicle-related traffic on motorways are sent into the atmosphere. Along with many pollutants from motor vehicles because of fossile fuel usage, heavy metals are also emitted as particles with exhausted gas. Heavy metals are one of the important parameters among environmental pollution sources. Heavy metals from motor vehicles may be found as PM in motorway atmosphere and be involved in street dust by depositing on roads as atmospheric precipitates. Bridge tollhouses are one of the most closely encountered environments of human beings with this kind of dust. In this study, time-related changes of atmospheric precipitate depositing per unit area were determined on breathing height of tollhouse workers, as well as concentrations of lead (Pb), copper (Cu), zinc (Zn), cadmium (Cd), and nickel (Ni) were measured. The study area was Istanbul Bosphorus Bridge, which is one of the busiest points of the world (referred to as the junction point of Asia and Europe) after it was merged to international D-100 motorway. According to the results obtained from the samples collected in ten different times during thirteen months, average lead concentration was found to be 1454.65 mg/kg dry soil, where the concentrations of copper, zinc, cadmium, and nickel were 399.12, 2034.78, 24.37, and 140.92 mg/kg dry soil, respectively.Öğe Modeling of Methane Distribution in a Landfill Using Genetic Algorithms(Mary Ann Liebert, Inc, 2009) Ozcan, H. Kurtulus; Balkaya, Nilgun; Bilgili, Erdem; Demir, Goksel; Ucan, O. Nuri; Bayat, CumaLandfill gas (LFG) results from the biologic decomposition of municipal waste and consists of mostly methane (CH4) and carbon dioxide (CO2), as well as trace amounts of a variety of other compounds. In this study, the major landfill gas emissions produced in Istanbul Hasdal landfill were investigated and modeled. In the investigated area, CH4, CO2, and O-2 measurements were made for 3.5 years in order to monitor long-term variations. In addition, a supervised algorithm for the evaluation of CH4 concentration using a genetic algorithm (GA) was developed and applied to real data. The model and the actual measurement results were compared and statistically evaluated. It was observed that the long term changes of the CH4 concentrations can be estimated effectively by the GA model structure. A correlation with 0.86 value was ascertained between the actual values and model results. The results of the study indicated that the GA can be used in modeling landfill gases generated in solid waste deposition areas.Öğe Modeling of trophospheric ozone concentrations using genetically trained multi-level cellular neural networks(Science China Press, 2007) Ozcan, H. Kurtulus; Bilgil, Erdem; Sahin, Ulku; Ucan, O. Nuri; Bayat, CumaTropospheric ozone concentrations, which are an important air pollutant, are modeled by the use of an artificial intelligence structure. Data obtained from air pollution measurement stations in the city of Istanbul are utilized in constituting the model. A supervised algorithm for the evaluation of ozone concentration using a genetically trained multi-level cellular neural network (ML-CNN) is introduced, developed, and applied to real data. A genetic algorithm is used in the optimization of CNN templates. The model results and the actual measurement results are compared and statistically evaluated. It is observed that seasonal changes in ozone concentrations are reflected effectively by the concentrations estimated by the multilevel-CNN model structure, with a correlation value of 0.57 ascertained between actual and model results. It is shown that the multilevel-CNN modeling technique is as satisfactory as other modeling techniques in associating the data in a complex medium in air pollution applications.Öğe NEW OPPORTUNITIES FOR TURKEY WITHIN THE GLOBAL CLIMATE CHANGE REGIME(Int Scientific Conference Sgem, 2008) Bal, Pinar; Bayat, CumaOver the last couple of decades, climate change has emerged to be one of the most complex challenges of the 21(st) century. As a result of the international cooperation achieved over the years, a global climate change regime has been established governed by climate politics. Over the last 50 years, the impacts of climate change have reached measurable dimensions. The fact that the average temperature of the earth's surface that is closer to the atmosphere has risen by 0.6 degrees C over the 20(th) century as well as 10-15% decrease in the glacier dimensions between 1950-2000 have given impetus to scientific research and international cooperation. This paper, after highlighting the major outcomes of the most recent international conference on climate change; the Bali Conference held in December, in Bali, Indonesia; attempts to evaluate Turkey's position within the global climate change regime. Accordingly, first, the critical time period until the end of 2009, emanating from the Bali Action Plan, has been underlined. The importance of conducting negotiations within this time period has been emphasized as a precondition for Turkey to become an active part of the global climate change regime in the post-2012 period with those terms which she can afford to deliver as well as an important complement of her sustainable development policies. In this respect, some alternatives have been proposed with the aim of holding some light on these critical negotiations.Öğe Prediction of Tropospheric Ozone Concentration by Employing Artificial Neural Networks(Mary Ann Liebert, Inc, 2008) Ozdemir, Huseyin; Demir, Goksel; Altay, Gokmen; Albayrak, Sefika; Bayat, CumaAir pollution modeling and prediction have great importance in preventing the occurrence of air pollution episodes and provide sufficient time to take the necessary precautions. Recently various algorithms such as artificial neural networks (ANNs) is applied to air quality modeling. The present work aims to predict tropospheric ozone concentration by the ANN with three pollutant parameters and eight meteorological factors in selected areas. We have preferred three-layer perceptron type of ANNs, which consists of input, hidden, and output layers, respectively. To evaluate the performance of the ANN model, selected statistical performance parameters are used. The overall system finds correlation parameter, r between 0.8 and 0.9 for the test data sets. Therefore, results show the successful follow of estimated ozone concentrations by the model with the observed values. Finally, it was seen that the ANN is one of the compromising methods in estimation of environmental complex air pollution problems.Öğe Reactive extraction and LSER model consideration of lactic acid with tripropylamine plus organic solvent systems from aqueous solution at room temperature(Elsevier Science Bv, 2009) Uslu, Hasan; Bayat, Cuma; Gokmen, Selahattin; Yorulmaz, YavuzThe extraction of lactic acid was done by tripropylamine (TPA) dissolved in seven single solvents (isoamyl alcohol, heptan-1-ol. hexan-1-ol. octan-1-ol, nonan-1-ol. decan-1-ol, and dodecanol). All measurements were carried out at 298.15 K. The extent to which the organic phase may be loaded with lactic acid is expressed as loading ratio, Z its value extraction efficiencies. E, and overall particular distribution coefficients, D, were calculated. Equilibrium complexation constants for(acid:amine) (1:1), (1:2) have been determined according to Bizek's approach. The maximum removal of lactic acid accomplished was about 81% with isoamyl alcohol having 1.935 mol dm(-3) initial concentration of TPA. All of the obtained data have been correlated by linear solvation energy relationship (LSER) model. LSER model results were compared with the experimental results and well agreement between them was observed. Regression coefficient (R(2)) of LSER model is 0.972. (C) 2009 Elsevier B.V. All rights reserved.Öğe Reactive Extraction of Formic Acid by Amberlite LA-2 Extractant(Amer Chemical Soc, 2009) Uslu, Hasan; Bayat, Cuma; Goekmen, Selahattin; Yorulmaz, YavuzThe reactive extraction of formic acid by Amberlite LA-2 dissolved in five different esters (dimethyl phthalate, dimethyl adipate, dimethyl succinate, dimethyl glutarate, diethyl carbonate), five different alcohols (isoamyl alcohol, hexan-1-ol, octan-1-ol, nonan-1-ol, decan-1-ol), and two different ketones (diisobutyl ketone (DIBK), methylisobutyl ketone (MIBK)) as diluents as well as the extraction capacity of pure diluent alone have been studied at isothermal conditions. All measurements have been carried out at 298.15 K. The comparison of physical and reactive extractions has been studied. The loading factor, T(T), extraction efficiency, E, modified separation factor, S(F), and distribution coefficients, K(D), have been calculated. The isoamylalcohol has been found to be the most effective solvent with a maximum distribution value of 19.223. Furthermore, the linear solvation energy relationship (LSER) model equation has been obtained to calculate distribution coefficients for alcohols with an R square of 0.976.Öğe Separation of 2,4,6-trinitrophenol from aqueous solution by liquid-liquid extraction method: Equilibrium, kinetics, thermodynamics and molecular dynamic simulation(Elsevier Science Sa, 2016) Uslu, Hasan; Datta, Dipaloy; Santos, Dheiver; Bamufleh, Hisham S.; Bayat, CumaIn this paper, the equilibrium and kinetic studies on the extraction of 2,4,6-trinitrophenol (picric acid) (0.021-0.061 kmol m(-3)) using Amberlite LA2, a secondary amine (ALA2: 0.118-0.588 kmol m(-3)) dissolved in a polar active solvent, methyl-iso-butyl ketone (MIBK) are performed. Also, the temperature effect (293.2 +/- 1 K, 303.2 +/- 1 K and 313.2 +/- 1 K) on the extraction mechanism and efficiency is evaluated. Thermodynamic parameters like the change in entropy and enthalpy are determined. From the values of loading ratio (Z < 0.5), it is inferred that the amine molecule form 1:1 complex with the acid molecule in the organic phase. The mass transfer coefficient (k(L), = 3.1 x 10(-5) m s(-1)) of picric acid in MIBK is determined. The Hatta number is calculated, and observed to vary in the range of 0.0032-0.0054, indicating that there is a very slow chemical reaction taking place between the acid and the amine molecule in the bulk of the organic phase. The reaction order is estimated to be 0.9 w.r.t picric acid, and 0.6 w.r.t ALA2 with rate constants of 14.95 x 10(-6) (kmol m(-3))(-0.5) s(-1), and 8.94 x 10(-7) (kmol m(-3))(-0.5) s(-1), for forward and backward reaction, respectively. Kinetic and potential energies of components during reactive extraction have been determined by molecular dynamic modeling. (C) 2016 Elsevier B.V. All rights reserved.Öğe SHIP WASTE FORECASTING AT THE BOTAS LNG PORT USING ARTIFICIAL NEURAL NETWORKS(Parlar Scientific Publications (P S P), 2008) Satir, Tanzer; Demir, Hasan; Alkan, Gueler B.; Ucan, Osman N.; Bayat, CumaCargo and passenger vessels are required to give their waste to reception facilities when at port, and due to new regulations Turkish ports need to establish or reconstruct these facilities. It is thus very important for ports to be able to predict the quantity of waste. In this study, the authors use Artificial Neural Networks (ANNs) to model four years of data on the reception of ship's waste at the Botas LNG Port in Marmara Ereglisi, Turkey. Satisfactory results are obtained by the ANN outputs. and confirmed by classical approaches. This ANN forecasting model can be used by waste management companies to plan new ports.Öğe Solid/Liquid Extraction Of Copper (Cu) From Municipal Solid Waste Compost(Beykent Üniversitesi, 2007) Bayat, Cuma; Elmaslar Ozbas, Emine; Celik, TuncerCompost can be used as a soil conditioner as it contains major plant nutrients, such as N, P, and K, microplant nutrients such as Cu, Fe, and Zn, and organic matter, which improves the physical properties in order to have a better soil aeration and water holding capacity. The presence of organic and inorganic contaminants in compost may, however, constitute a danger to the environment. It is the heavy metal content which is the main factor leading to restricted agricultural use of compost. Literature on the effect of compost use on heavy metal levels in the environment shows it to vary according to soil type, plant species and compost quality. This paper deals with the removal of copper from Municipal Solid Waste (MSW) compost using Na2EDTA solution and a mixture of Na2S2O5 (sodium metabisulfite) solution and Na2EDTA solution in the batch mode. At the end of extraction studies, for 3 hours at 1:25 solid:liquid ratio by using 0.05 M Na2EDTA solution, 100% removal yield was obtained for Cu. 100% heavy metal removal yield was obtained with 0.01 M Na2EDTA and 0.1 M Na2S2O5, at 1:6 solid:liquid ratio, for Cu in this study.
