Yazarlar
- Kul, Sinan(13)
- Yıldırım, Ümit(9)
- Duran, Celal(6)
- Serencam, Huseyin(6)
- Ekmekyapar Torun, Fatma(5)
- Eryılmaz Türkkan, Gökçen(5)
- Güven, Onur(5)
- Kurt, Mehmet Ali(5)
- Ozdes, Duygu(5)
- Cengiz, Ibrahim(4)
- Torun, Fatma Ekmekyapar(4)
- İrdemez, Şahset(4)
- Bingül, Züleyha(3)
- Boncukcuoğlu, Recep(3)
- Guler, Cuneyt(3)
- Hırca, Tuğçe(3)
- Jomaa, Seifeddine(3)
- Niazkar, Majid(3)
- Nuhoglu, Alper(3)
- Nuhoğlu, Alper(3)
- Serencam, Hüseyin(3)
- Teke, Çağatay(3)
- Tufekci, Mehmet(3)
- Uçurum, Metin(3)
- Yildiz, Ergun(3)
- Özdemir, Akın(3)
- Celebi, Neslihan(2)
- Cengiz, İbrahim(2)
- Degermenci, Nejdet(2)
- Demircioğlu, Nuhi(2)
- Gundogdu, Ali(2)
- Güler, Cüneyt(2)
- Kalkan, Ekrem(2)
- Karakaş, İbrahim Hakkı(2)
- Karcioğlu Karakaş, Zeynep(2)
- Korkmaz, Serdar(2)
- Korkmaz, Serol(2)
- Kul, S.(2)
- Nadaroglu, Hayrunnisa(2)
- Reçber, Züleyha(2)
Yayınlar
- MakaleYalnız künye2017Scopus SJRQ2Adsorptive properties of As(III) from aqueous solution using magnetic nickel ferrite (NiFe2O4) nanoparticles: Isotherm and kinetic studies
Karcioğlu Karakaş, Zeynep; Boncukcuoğlu, Recep; Karakaş, İbrahim Hakkı
As(III) adsorption on NiFe2O4 nanoparticles were systematically investigated by controlling parameters such as stirring rate, pH, initial arsenic concentration, contact duration, temperature, and adsorbent dose. It was observed that the amount of adsorbed arsenic concentration is strongly depended on pH and temperature. The temperature and pH give rise to significant changes in the amount of adsorbed arsenic. As compared with Langmuir and Freundlich isotherms models, the latter is found to be well suited. Pseudo-first order, pseudo-second order, and intraparticle diffusion models were applied to adsorption equilibrium data obtained from the analysis of arsenic with diverse amount of initial concentration.
AtıfScopus12WoS13OpenAlex11İncele
- MakaleAçık Erişim2016Scopus SJRQ1Performance investigation of a jet loop membrane bioreactor for the treatment of an actual olive mill wastewater
Değermenci, Nejdet; Cengiz, İbrahim; Yildiz, Ergun; Nuhoglu, Alper
In this study, following the pre-treatment of olive mill wastewater (OMW), its treatment in a jet loop membrane bioreactor (JLMBR) was investigated. Among the pre-treatment options, the configuration composed of physical settling, cartridge filter and ceramic membrane showed the best performance in terms of investigated parameters. For the JLMBR that was fed by pretreated OMW, up to 93 and 87% removal efficiencies were achieved for the chemical oxygen demand (COD) and total phenol, respectively, at volumetric organic load (VOL) of 17.8 kg COD/m3 day. The calculated specific oxygen uptake rate (SOUR) values were in the range 7.7–34.7 g O2/kg MLVSS h. When even hydraulic retention times (HRT) values decreased by a factor of 1:24, system performance in terms of COD and total phenol removal remained almost stable. Decreasing the sludge retention time (SRT) to three days made considerable perturbations for the system performance, increasing the effluent COD and total phenol values in 900 and 80 mg/L, respectively. The JLMBR showed a high overall performance for the treatment of an actual OMW under the evaluated operational conditions.
AtıfScopus33WoS28OpenAlex33İncele
- BildiriYalnız künye2015Scopus SJRQ3Removal of Reactive Black 5 from wastewater using natural clinoptilolite modified with apolaccase
Nadaroglu, Hayrunnisa; Kalkan, Ekrem; Celebi, Neslihan; Tasgin, Esen
In this study, a clinoptilolite modified with apolaccase was used to adsorb Reactive Black 5 (RB5) dye from aqueous solution using the batch procedure. The influences of pH, contact time, temperature and absorbent dosage on the adsorption were investigated. The optimum adsorption was obtained at pH = 6, contact time = 60 min, temperature = 25 degrees C and adsorbent dosages of 1.62 and 1.59 mg/50 mL per gram of clinoptilolite and of apolaccase-modified clinoptilolite (LMC), respectively). The adsorption experimental data fitted both the Langmuir and Freundlich isotherm models well. In addition, pseudo-first-order and pseudo-second-order kinetics were used to study the kinetics of RB5 dye adsorption onto natural clinoptilolite and LMC. Adsorption appears to follow pseudo-second-order kinetics with a high correlation coefficient. Thermodynamic parameters such as changes in the free energy (Delta G degrees), enthalpy (Delta H degrees) and entropy (Delta S degrees) of adsorption were calculated. The thermodynamic parameters indicate that the adsorption of RB5 dye onto LMC was less spontaneous, feasible and endothermic. The LMC can be used as an alternative low-cost adsorbent for the dye removal from aqueous solutions.
AtıfWoS8OpenAlex8İncele
- MakaleAçık Erişim2015Scopus SJRQ2Simultaneous separation and preconcentration of Cd(II), Co(II), and Ni(II) ions in environmental samples by carrier element-free coprecipitation method prior to their flame atomic absorption spectrometric determination
Duran, Celal; Ozdes, Duygu; Akcay, Hakki Turker; Serencam, Huseyin; Tufekci, Mehmet
ABSTRACT: In the present study, Cd(II), Co(II), and Ni(II) ions were separated and preconcentrated via carrier element-free coprecipitation (CEFC) method by using an organic coprecipitating agent, 1,2-bis-(2-tosyl ethoxy) benzene (BTEB), prior to their flame atomic absorption spectrometric (FAAS) detections. The experimental conditions were optimized in terms of pH of the aqueous solution, BTEB amount, standing time, centrifugation rate and time, and sample volume. Under the optimum experimental conditions, the detection limits for Cd(II), Co(II), and Ni(II) ions were found to be 0.13, 0.67, and 0.46 μg L−1, respectively, and the relative standard deviations for the analyte ions were found to be lower than 4.0%. The accuracy of the method was tested by analyzing certified reference material and spike tests. The method was applied to determine the levels of Cd(II), Co(II), and Ni(II) ions in sea and stream water, macaroni, red lentil, and cracked wheat samples.
AtıfScopus17WoS16OpenAlex16İncele
- MakaleAçık Erişim2015Scopus SJRQ2Experimental study to remediate acid fuchsin dye using laccase-modified zeolite from aqueous solutions
Kalkan, Ekrem; Nadaroglu, Hayrunnisa; Celebi, Neslihan; Celik, Hulya; Tasgin, Esen
This paper studies, the removal of acid fuchsin dye from aqueous solutions using zeolite natural material after its modification with laccase from Russulaceae (Lactarius volemus). Batch adsorption experiments were performed as a function of pH, contact time, temperature, and adsorbent dosage. The optimum results were obtained at pH 5, contact time of 60 min, temperature of 60ºC, and an adsorbent dosage of 1.5 mg/mL. The isotherm studies show that the adsorption experimental data are fitted well by Langmuir isotherm model. The adsorption capacity found is 31 mg/g. The kinetics of AFD adsorption on LMZ is best described with the pseudo-first-order kinetics model. Thermodynamic parameters including Gibbs free energy, enthalpy, and entropy changes indicate that the adsorption of Acid Fuchsin dye onto laccase-modified zeolite is feasible, spontaneous, and exothermic. The results show that laccase-modified zeolite can be used as an alternative lowcost adsorbent for dye removal from aqueous solutions.
AtıfScopus33WoS27OpenAlex29İncele
- MakaleAçık Erişim2015Scopus SJRQ2Decontamination of Escherichia coliO157: H7 and Staphylococcus aureus from Fresh-Cut Parsley with Natural Plant Hydrosols
Törnük, Fatih; Dertli, Enes
The inhibitory effects of sage, rosemary, oregano and thyme hydrosols were evaluated against Escherichia coliO157:H7 and Staphylococcus aureus inoculated on parsley at high and low concentrations. Following the pathogen inoculations, parsley samples were washed with the hydrosols and sterile tap water as a control for 0, 20, 40 and 60min, and reductions on pathogen counts were determined. Sterile tap water was ineffective on all conditions tested. After 20min of application, oregano and thyme hydrosols were able to significantly (P<0.05) reduce E.coliO157:H7 counts on low inoculum level, while all hydrosols showed significant reductions (P<0.05) on high inoculum levels at this period. Additional reductions on E.coliO157:H7 counts were observed with the increasing time. S.aureus was more sensitive to hydrosol treatments, and oregano hydrosol was able to completely eliminate S.aureus after 40min. In conclusion, decontamination of foodborne pathogens from fresh-cut vegetables can be achieved by hydrosol treatments.
AtıfScopus14WoS11OpenAlex16İncele
- MakaleAçık Erişim2014Scopus SJRQ2Assessment of kinetics, thermodynamics, and equilibrium parameters of Cu(II) adsorption onto Rosa canina seeds
Serencam, Huseyin; Ozdes, Duygu; Duran, Celal; Senturk, Hasan Basri
Rosa canina seeds (RCS) is considered as a low-cost and promising adsorbent in removal of metal ions; hence, in the present study, we aimed to test the adsorptive removal of Cu(II) ions from aqueous solutions by utilizing RCS in a batch process. After characterization of RCS by using several techniques, the effects of various experimental parameters such as initial pH of aqueous solution, contact time, initial Cu(II) concentration, RCS concentration, temperature, and electrolyte concentration were studied upon the adsorption process. The desorption conditions of Cu(II) ions from the loaded RCS were also evaluated. Maximum Cu(II) adsorption was found to occur at pH 6.0 and the equilibrium was established after 60 min of contact time. The adsorption isotherms were described by means of Langmuir, Freundlich, Temkin, and Dubinin Radushkevich models. The adsorption kinetics were analyzed using pseudo-first-order, pseudo-second-order, Elovich and intraparticle diffusion models and the adsorption data were well described by the pseudo-second-order model. Thermodynamic parameters such as the Gibbs free energy (ΔG), enthalpy (ΔH), and entropy (ΔS) changes were also evaluated and it has been found that the adsorption process was feasible, spontaneous, and endothermic in the temperature range of 278-313 K.
AtıfScopus19WoS20OpenAlex19İncele
- MakaleAçık Erişim2014Scopus SJRQ1Simultaneous separation and preconcentration of Ni(II) and Cu(II) ions by coprecipitation without any carrier element in some food and water samples
Duran, Celal; Tumay, Sureyya O.; Ozdes, Duygu; Serencam, Huseyin; Bektas, Hakan
A simple and highly sensitive separation and preconcentration procedure, which has minimal impact on the environment, has been developed. The procedure is based on the carrier element-free coprecipitation of Ni(II) and Cu(II) ions by using 2-{4-[2-(1H-Indol-3-yl)ethyl]-3-(4-chlorobenzyl)-5-oxo-4,5-dihydro-1H-1,2,4-triazol-1-yl}-N′-(pyrrol-2-ylmethyliden)acetohydrazide (ICOTPA), as an organic coprecipitant. The levels of analyte ions were determined by flame atomic absorption spectrometry. The detection limits for Ni(II) and Cu(II) ions were found to be 0.27 and 0.58 μg L-1, respectively, and the relative standard deviations for the analyte ions were lower than 4.0%. Spike tests and certified reference material analyses were performed to validate the method. The method was successfully applied for the determination of Ni(II) and Cu(II) ions levels in sea and stream water as liquid samples and red lentil and rice as solid samples.
AtıfScopus26WoS23OpenAlex26İncele
- MakaleAçık Erişim2013Scopus SJRQ2Biosorption properties of Morus alba L. for Cd (II) ions removal from aqueous solutions
Serencam, Huseyin; Ozdes, Duygu; Duran, Celal; Tufekci, Mehmet
The abundantly available industrial waste product Morus alba L. pomace (MAP) is one of the cost-effective biosorbent for removal of metal ions from aqueous solutions. Hence, in the present study, we aimed to test the ability of MAP to remove Cd(II) ions through batch biosorption process. Firstly, MAP was characterized using several techniques, and then the influence of various experimental parameters such as initial pH of the aqueous solution, initial Cd(II) concentration, contact time, MAP concentration, and temperature were evaluated upon the biosorption process. It was found that the maximum uptake of Cd(II) ions occurred at initial pH 6.0 and optimum contact time was observed as 60 min. Cd(II) ions adsorption on MAP analyzed by the Langmuir and Freundlich isotherm models and the maximum monolayer biosorption capacity of MAP was found to be 21.69 mg g-1 by using the Langmuir isotherm model. The pseudo-first-order, pseudo-second-order, Elovich, and intraparticle diffusion models were employed to describe the biosorption kinetics. In order to investigate the thermodynamic properties of the biosorption process, the changes in the Gibbs free energy (â̂†G), enthalpy (â̂†H), and entropy (â̂†S) were also evaluated and it has been concluded that the process was feasible, spontaneous, and endothermic in the temperature range of 5-40 C.
AtıfScopus38WoS36OpenAlex46İncele
- MakaleYalnız künye2013Scopus SJRQ2Separation and pre-concentration of palladium(II) from environmental and industrial samples by formation of a derivative of 1,2,4-triazole complex on Amberlite XAD-2010 resin
Serencam, Huseyin; Bulut, Volkan Numan; Tufekci, Mehmet; Gundogdu, Ali; Duran, Celal; Hamza, Sibel; Soylak, Mustafa
A simple separation/pre-concentration method was developed for extraction of Pd(II) in various environmental samples, based on its adsorption of 4-phenyl-5-{[(4-phenyl-5-pyridin-4-yl-4H-1,2,4-triazole-3-yl)thio]methyl}-4H-1,2,4-triazole-3-thyol (PPTTMET) complex on Amberlite XAD-2010 resin in a mini column. The ligand has high affinity for Pd(II) among many other metals that are taken into consideration. The flame atomic absorption spectrometry is employed to determine the concentration of Pd(II). The optimum working conditions which were determined are as follows: 0.05 mol L-1 HNO3 as working medium, 1.0 mol L-1 HCI in acetone as elution solvent, 0.75 mg of PPTTMET amount and 750 mL of sample volume. The system was independent from the flow rates between 3.1 and 23.1 mL min-1. The Pd(II) adsorption capacity of Amberlite XAD-2010 resin was found to be 12.8 mg g-1 and the enrichment factor was calculated as 375. The method was successfully applied for the determination of Pd(II) in motorway dust samples, anodic sludge, gold ore, industrial electronic waste materials and various water samples.
AtıfScopus17WoS15OpenAlex17İncele
- MakaleYalnız künye2012Scopus SJRQ1Adsorption of phenol from aqueous solution on a low-cost activated carbon produced from tea industry waste: Equilibrium, kinetic, and thermodynamic study
Gundogdu, Ali; Duran, Celal; Senturk, H. Basri; Soylak, Mustafa; Ozdes, Duygu; Serencam, Huseyin; Imamoglu, Mustafa
The ability of activated carbon which was produced by chemical activation using zinc chloride from tea industry wastes (TIWAC) to adsorb phenol molecules from aqueous solution was tested by equilibrium, kinetic, and thermodynamic parameters. Phenol adsorption on TIWAC took place with a high yield at pH values in the range 4 to 8. The optimum contact period was observed as 4.0 h and from the adsorption graphs plotted as a function of time; it was established that phenol adsorption on TIWAC conformed more to a pseudosecond-order kinetic model. Additionally, it was determined that the adsorption rate is controlled by intraparticle diffusion as well as film diffusion. It was established that phenol adsorption on TIWAC can be better defined by the Langmuir adsorption model and its adsorption capacity was 142.9 mg·g-1 from the linear Langmuir equation. Temperature had an adverse effect on adsorption yield, and hence, the adsorption process was exothermic in our case. Moreover, increasing electrolyte concentration in the medium has a positive effect on adsorption yield. From the data obtained, it was concluded that the removal of phenol from aqueous solution by TIWAC produced from tea industry wastes with a very low cost took place with an extremely high performance.
AtıfScopus228WoS212OpenAlex222İncele
- MakaleYalnız künye2011Scopus SJRQ2Statistical Downscaling of Monthly Precipitation Using NCEP/NCAR Reanalysis Data for Tahtali River Basin in Turkey
Fistikoglu, Okan; Okkan, Umut
Statistical downscaling methods describe a statistical relationship between large-scale atmospheric variables such as temperature, humidity, precipitation, etc., and local-scale meteorological variables like precipitation. This study examines the potential predictor variables selected from the National Center for Environmental Prediction and National Center for Atmospheric Research (NCEP/NCAR) reanalysis data set for downscaling monthly precipitation in Tahtali watershed in Turkey. An approach based on the assessment of all possible regression types was used to select the predictors among the NCEP reanalysis data set, and artificial neural network (ANN)-based downscaling models were designed separately for each station in the basin. The results of the study showed that precipitation, surface and sea level pressures, air temperatures at surface, 850-, 500-, and 200-hPa pressure levels, and geopotential heights at 850- and 200-hPa pressure levels are the most explanatory NCEP/NCAR parameters for the study area. It was concluded that ANN-based downscaling models can be implemented to downscale coarse-scale atmospheric parameters to monthly precipitation at station scale by using the above parameters as inputs in the study area.
AtıfWoS65OpenAlex86İncele
- MakaleAçık Erişim2011Scopus SJRQ1Effect of photosonication treatment on inactivation of total and coliform bacteria in milk
Şengül, Mustafa; Erkaya, Tuba; Başlar, Mehmet; Ertugay, M. Fatih
The combined effect of simultaneously applied acoustic energy and ultraviolet irradiation (UV-C), named photosonication, on the population reduction of total and coliform bacteria in raw milk was investigated. Photosonication was carried out at 100% (120 μm; 240 W) amplitude of ultrasound accompanied by UV light of 13.2 W cm-2 while sonication was carried out at 100% amplitude without UV light. An ultrasonic processor (400 W and 24 kHz with a 22 mm diameter probe) and 3 ultraviolet lamps (4400 μW cm-2 per lamp) were used. The exposure time was 15 min for all treatment, and samples were taken after 0, 3, 6, 9, 12 and 15 min. Thermal treatment (at 65 °C for 30 min) achieved a 3.29 log and 5.31 log-reduction for total and coliform bacteria, respectively. However, the reduction achieved was 4.79 log cfu mL-1 and 5.31 log cfu mL-1 for total and coliform bacteria, respectively, in photosonication while 1.31 log cfu mL-1 and 4.01 log cfu mL-1 for total and coliform bacteria, respectively in sonication. During photosonication, UV light contributed to an increase of lethality.
AtıfScopus33WoS32OpenAlex39İncele
- MakaleAçık Erişim2010Scopus SJRQ1Thermodynamics and kinetic studies of biosorption of a basic dye from aqueous solution using green algae Ulothrix sp.
Doǧar, Çetin; Gürses, Ahmet; Açikyildiz, Metin; Özkan, Esra
This study addresses removal of a basic dye, methylene blue, from aqueous solutions by using dried Ulothrix sp. biomass as biosorbent. The effects of the initial dye concentration, contact time, temperature, solution equilibrium pH, biosorbent dosage, and mixing rate on biosorption of the dye have been investigated. It was found that 30 min is sufficient in order to reach adsorption equilibrium. The amount of methylene blue adsorbed onto Ulothrix sp. increased with increasing equilibrium pH and mixing rate, in contrary, it decreased with increasing temperature and sorbent dosage. The process followed the pseudo-second-order kinetic model. The isosteric enthalpy and entropy values were calculated as -11.8 kJ/mol and 37.5 J/(mol K), respectively. In addition, the results suggest that the physical interactions between sorbent particles and sorbate ions play an important role for the adsorption of methylene blue onto the biosorbent.
AtıfScopus80WoS74OpenAlex85İncele
- MakaleYalnız künye2008Scopus SJRQ1The removal of lignin and phenol from paper mill effluents by electrocoagulation
Uǧurlu, M.; Gürses, A.; Doǧar, Ç.; Yalçin, M.
This study aims to investigate the treatment of paper mill effluents using electrocoagulation. Removal of lignin, phenol, chemical oxygen demand (COD) and biological oxygen demand (BOD) from paper mill effluents was investigated at various current intensities by using different electrodes (Al and Fe) and at various electrolysis times (1.0, 2.5, 5.0 and 7.5 min). It was observed that the experiments carried out at 12 V, an electrolysis time of 2 min and a current intensity of 77.13 mA were sufficient for the removal of these pollutants with each electrode. The removal capacities of the process using an Al electrode were 80% of lignin, 98% of phenol, 70% of BOD, and 75% of COD after 7.5 min. Using an Fe electrode the removal capacities were 92%, 93%, 80% and 55%, respectively. In addition, it was found that removal of lignin, phenol, BOD and COD increased with increasing current intensity. In the experiments carried out at different current intensities, higher removal can be explained through a decrease in intra-resistance of solution and consequently an increase at the transfer speed of organic species to electrodes. It was also found that Al electrode performs higher efficiency than Fe electrode except for COD removal. However, the time required for removal of BOD was more than that of COD. The results suggest that electrocoagulation could be considered as an effective alternative to paper mill effluents treatment.
AtıfScopus257OpenAlex275İncele
