Zümriye Aksu

Ankara University, Engüri, Ankara, Turkey

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Publications (81)211.16 Total impact

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    Dataset: ozturk1999
  • Zümriye Aksu, Ahmet Burak Akın
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    ABSTRACT: Biosorption of Remazol Black B, a vinyl sulfone type reactive dye, from aqueous solution was investigated to compare the binding capacities of untreated (live) and treated (dried, autoclaved, acid (H2SO4)-treated, base (NaOH)-treated) activated sludge in this study. Remazol Black B uptake was strongly affected by the solution pH and optimum adsorption pH value was determined as 2 for all the live and treated activated sludge biosorbents. It was seen that the sorption capacity of each biosorbent enhanced with decreasing temperature. Dye uptake also increased with increasing initial dye concentration up to 500 mg l−1 for each biomass type. Contrary to assumption it is found that all the treatment methods diminished the dye biosorption capacity of activated sludge. Among the five biosorbents, live activated sludge had a maximum dye uptake capacity of 134.8 mg g−1 at 25 °C. The Langmuir–Freundlich adsorption model described the equilibrium data of each dye–biosorbent system accurately in the concentration and temperature ranges studied. The pseudo-second-order adsorption model defined the overall adsorption kinetics of each biosorption process exactly.
    Chemical Engineering Journal 11/2010; · 4.06 Impact Factor
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    ABSTRACT: The biosorption of Methylene Blue, a cationic dye, onto dried Rhizopus arrhizus, a filamentous fungus, was examined in the absence and in the presence of increasing concentrations of sodium dodecylsulfate (SDS), an anionic surfactant. The fungus exhibited the maximum dye uptake at an initial pH value of 10 in the absence of surfactant. The addition of SDS did not change the initial pH of maximum dye uptake. Dye uptake by the fungus increased with increasing initial dye concentration up to 1100 mg l−1. The presence of 1 mM surfactant in biosorption medium enhanced the dye removal dramatically. The Freundlich model better described the equilibrium dye uptake than the Langmuir model. According to the Langmuir model, the maximum dye uptake was determined as 370.3 mg dye g−1 of dried biomass in the absence of surfactant. When 1 mM (288.4 mg l−1) SDS was added to the biosorption medium, this value raised to 1666.6 mg g−1 resulting in 4.5-fold increase in uptake capacity. The pseudo-second-order kinetic model described the biosorption kinetics accurately for all cases studied confirming that a chemisorption process controls the sorption rate.
    Chemical Engineering Journal 04/2010; · 4.06 Impact Factor
  • Z Aksu, E Balibek
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    ABSTRACT: In this study the biosorption of Yellow RL, a metal-complex anionic dye, by dried Rhizopus arrhizus, a filamentous fungus, was investigated as a function of initial solution pH, initial dye concentration and initial salt (sodium chloride) concentration. The fungus exhibited the maximal dye uptake at pH 2 in the absence and in the presence of salt. Dye uptake increased with the dye concentration up to 1000 mg l(-1) and diminished considerably in the presence of increasing concentrations of salt up to 50 g l(-1). The fungus biosorbed 85.4 mg dye g(-1)of dried biomass at 100 mg l(-1) initial dye concentration in the absence of salt. When 50 g l(-1) salt was added to the biosorption medium, this value dropped to 60.8 mg g(-1) resulting in 28.8% reduction in biosorption capacity. The Redlich-Peterson and Langmuir-Freundlich were the most suitable adsorption models for describing the biosorption equilibrium data of the dye both individually and in salt containing medium. The pseudo-second-order and saturation type kinetic models depicted the biosorption kinetics accurately for all cases studied. Equilibrium and kinetic constants varied with the level of salt were expressed as a function of salt concentration.
    Journal of Environmental Management 03/2010; 91(7):1546-55. · 3.06 Impact Factor
  • Ferda Gönen, Zümriye Aksu
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    ABSTRACT: The single and binary effects of initial Remazol Turquoise Blue-G (RTBG) reactive dye and initial copper(II) concentrations on the dye or/and copper(II) bioaccumulation efficiency of C. tropicalis was investigated in 10 g l(-1) molasses sucrose containing growth medium at an initial pH value of 4.0 and optimized using response surface methodology (RSM). A 2(2) full factorial central composite design was successfully used for experimental design and analyses of the results. Two numerical correlations fitted to a second-order quadratic equation were obtained to estimate the responses of dye and copper(II) removal yields. The statistical analysis indicated that although relatively high accumulation efficiency of C. tropicalis was obtained for the single removal of dye and copper(II), individual uptake of both the components from binary mixture was affected negatively by the addition of other component up to 500 mg l(-1) due to inhibition caused by high concentrations of RTBG dye and copper(II). The optimum combination predicted via RSM confirmed that growing C. tropicalis was capable of bioaccumulating RTBG and copper(II) with the maximum yields of 59.2% and 21.3% in the growth medium containing 50 mg l(-1) RTBG and 50 mg l(-1) copper(II) together, respectively.
    Journal of hazardous materials 09/2009; 172(2-3):1512-9. · 4.33 Impact Factor
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    ABSTRACT: Wastewaters of textile and leather dying industries may contain significant quantities of chromium(VI) ions besides anionic and water-soluble dyes. Moreover the temperature of these wastewaters may be a controlling parameter affecting the biosorption efficiency. In this study biosorption of chromium(VI) and Remazol Black B reactive dye by dried Phormidium sp., a thermophilic cyanobacterium, was studied as a function of initial chromium(VI) concentration and temperature in no dye and 100 mg l−1 dye-containing media at an initial pH value of 2.0 at which the biomass exhibited the maximum chromium(VI) and dye uptakes. The decrease of both metal and dye uptakes with temperature indicated that the uptakes were exothermic in nature. Equilibrium uptake of chromium(VI) enhanced considerably with both chromium(VI) and 100 mg l−1 dye concentrations. Moreover the presence of chromium(VI) also increased the uptake of dye. At 25 °C, 22.8 mg g−1 chromium(VI) and 91.3 mg g−1 dye were sorbed by the biomass in binary 100 mg l−1 chromium(VI) and 100 mg l−1 dye-containing medium. The Langmuir was the best suitable adsorption model for describing the biosorption of chromium(VI) individually and in dye-containing medium. The pseudo-second-order kinetic model described both the chromium(VI) and dye biosorptions kinetics accurately.
    Journal of hazardous materials 08/2009; · 4.33 Impact Factor
  • Ferda Gönen, Zümriye Aksu
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    ABSTRACT: The combined effects of initial sucrose and initial Remazol Turquoise Blue-G (RTBG) reactive dye concentrations on the specific growth rate and dye bioaccumulation efficiency of Candida utilis was investigated and optimized using response surface methodology (RSM) in this study. A 22 full factorial central composite design was successfully used for experimental design and analyses of the results. Two numerical correlations fitted to a second-order quadratic equation were obtained to estimate the responses of specific growth rate and dye uptake yield. The statistical analysis indicated that both the microbial growth and removal yield of dye enhanced with raising sucrose concentration up to 15 g l−1 and diminished with the increase in initial RTBG dye concentration up to approximately 500 mg l−1 due to inhibition caused by high concentrations of RTBG dye. The optimum combination predicted via RSM confirmed that C. utilis was capable of bioaccumulating RTBG with the maximum uptake yield of 82.0% in 15 g l−1 sucrose and 50 mg l−1 dye containing growth medium.
    Enzyme and Microbial Technology 07/2009; · 2.97 Impact Factor
  • Zümriye Aksu, Göknur Karabayir
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    ABSTRACT: Three kinds of filamentous fungi (Rhizopus arrhizus, Trametes versicolor, Aspergillus niger) were tested for their ability to adsorb Gryfalan Black RL metal-complex dye as a function of pH, temperature and dye concentration. R. arrhizus and T. versicolor exhibited the maximum dye uptake at pH 2.0 and at 25 degrees C while A. niger performed the highest dye biosorption at pH 1.0 and at 35 degrees C. Sorption capacity of each biosorbent increased with increasing initial dye concentration. Among the three fungi, R. arrhizus was the most effective biosorbent showing a maximum dye uptake of 666.7 mg g(-1). The Langmuir model described the equilibrium data of each dye-fungus system accurately in the concentration and temperature ranges studied. Kinetic analysis indicated that both adsorption kinetics and internal diffusion played an important role on controlling the overall adsorption rate for each fungus. Thermodynamic analysis verified that A. niger biosorption was endothermic while the others were exothermic.
    Bioresource Technology 12/2008; 99(16):7730-41. · 5.04 Impact Factor
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    ABSTRACT: In this study dried Trametes versicolor, a white-rot fungus and chitosan, a fungal component derivative were used for the removal of Acid Blue 161 (AB 161) acidic dye from aqueous solution and the results were compared with the outcomes of acid-washed powdered activated carbon (PAC). The influence of suspension pH, temperature, and initial dye concentration on AB 161 dye removal was investigated by conducting a series of batch adsorption experiments. All sorbents exhibited the highest dye uptake capacity at an initial pH value of 3.0. The effect of temperature on dye removal indicated that maximum capacity was obtained at 45°C for each AB 161 dye–sorbent system. Sorption capacity of each sorbent increased with increasing initial dye concentration up to 500mgl−1. Among the three sorbents, chitosan was the most effectively sorbent showing a maximum acidic dye uptake of 471.6mgg−1 at 45°C. The Freundlich, Langmuir, Redlich–Peterson and Langmuir–Freundlich, the two- and three-parameter adsorption models were used for the mathematical description of the sorption equilibrium and isotherm constants were evaluated depending on sorption temperature. Equilibrium data of AB 161 sorption fitted very well to all models except that the Freundlich model for each acid dye–sorbent system in the concentration and temperature ranges studied. For each sorbent–dye system simple kinetic models were applied to the experimental data to examine the mechanisms of sorption and potential rate-controlling steps such as external mass transfer, intraparticle diffusion and sorption process. The sorption process was found to be controlled by both surface and pore diffusion with surface diffusion at the earlier stages followed by pore diffusion at the later stages. Pseudo-second-order kinetic model described the adsorption kinetics accurately at all concentrations and temperatures studied. The thermodynamic analysis indicated that the sorption process was endothermic and the sorption of dye on each sorbent might be chemical in nature.
    Chemical Engineering Journal 08/2008; 142(1):23-39. · 4.06 Impact Factor
  • Ozlem Tunç, Hacer Tanaci, Zümriye Aksu
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    ABSTRACT: In this study, the potential use of cotton plant wastes - stalk (CS) and hull (CH) - as sorbents for the removal of Remazol Black B (RB5), a vinyl sulfone type reactive dye, was investigated. The results indicated that adsorption was strongly pH-dependent but slightly temperature-dependent for each sorbent-dye system. The Freundlich, Langmuir, Redlich-Peterson and Langmuir-Freundlich adsorption models were used for the mathematical description of adsorption equilibrium and isotherm constants were evaluated at 25 degrees C. All models except the Freundlich model were applicable for the description of dye adsorption by both sorbents in the concentration range studied. According to the Langmuir model, CS and CH sorbents exhibited the highest RB5 dye uptake capacities of 35.7 and 50.9 mg g(-1), respectively, at an initial pH value of 1.0. Simple mass transfer and kinetic models were applied to the experimental data to examine the mechanisms of adsorption and potential rate-controlling steps. It was found that both external mass transfer and intra-particle diffusion played an important role in the adsorption mechanisms of dye, and adsorption kinetics followed the pseudo second-order type kinetic model for each sorbent. Using the Langmuir model parameters, thermodynamic constant DeltaG degrees was also evaluated for each sorption system.
    Journal of Hazardous Materials 07/2008; 163(1):187-98. · 4.33 Impact Factor
  • Ferda Gönen, Zümriye Aksu
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    ABSTRACT: The influential factors on simultaneous growth and copper(II) bioaccumulation by growing cells of Candida utilis yeast under various ambient conditions, such as changing concentrations of molasses sucrose and copper(II) were tested. The highest growth rate of 0.133 h(-1) was obtained at an initial sucrose concentration of 15 g l(-1) in absence of copper(II). For each constant sucrose concentration chosen between 5 and 15 g l(-1), the increase in initial copper(II) concentration up to 500 mg l(-1) resulted in a decrease in the percentage uptake of copper(II) and moreover all copper(II) concentrations tested inhibited the yeast growth. On the other hand, at each constant copper(II) concentration studied, both the growth and copper(II) uptake yield enhanced with raising sucrose concentration up to 15 g l(-1). Maximum uptake yield of 34.2% was observed in 15 g l(-1) sucrose and 50 mg l(-1) copper(II) containing growth medium. The binary effects of initial sucrose and copper(II) concentrations on the specific growth rate and copper(II) uptake yield of yeast were analyzed by experimental design method and two model equations for predicting the growth rate and copper(II) uptake yield of yeast due to arbitrarily chosen sucrose and copper(II) concentrations were developed by using response surface methodology (RSM).
    Journal of Hazardous Materials 07/2008; 154(1-3):731-8. · 4.33 Impact Factor
  • Ferda Gönen, Zümriye Aksu
    Journal of Biotechnology 09/2007; 131(2). · 2.88 Impact Factor
  • Z Aksu, E Balibek
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    ABSTRACT: Some industrial wastewaters contain high quantities of salts besides heavy metal ions. The presence of salt ions leads to high ionic strength, which may significantly affect the performance of the biosorption process so the effect of salts on the biosorption of heavy metal ions should be investigated. In this study the biosorption of chromium(VI) from saline solutions on dried Rhizopus arrhizus was studied as a function of pH, initial chromium(VI) and salt (NaCl) concentrations in a batch system. The biosorption capacity of R. arrhizus strongly depended on solution pH and maximum chromium(VI) sorption capacity of sorbent was obtained at pH 2.0 both in the absence and in the presence of increasing concentrations of salt. Chromium(VI)-salt biosorption studies were performed at this pH value. Equilibrium uptakes of chromium(VI) increased with increasing chromium(VI) concentration up to 250mgl(-1) and decreased considerably by the presence of increasing concentrations of salt. At 100mgl(-1), initial chromium(VI) concentration, dried R. arrhizus biosorbed 78.0mgg(-1) of chromium(VI) in 72h without salt medium. When salt concentration was raised to 50gl(-1), this value dropped to 64.0mgg(-1) of chromium(VI) at the same conditions resulting in 17.9% decrease of biosorption capacity. The equilibrium sorption data were analysed by using Freundlich, Langmuir, Redlich-Peterson and Langmuir-Freundlich (Sips), the two and three parameters adsorption models, using non-linear regression technique and isotherm constants were evaluated depending on salt concentration. The Langmuir-Freundlich (Sips) was the best suitable adsorption model for describing the biosorption of chromium(VI) individually and in salt-containing medium. Pseudo-first-order, pseudo-second-order and saturation type kinetic models described the biosorption kinetics accurately at all chromium(VI) concentrations in the absence and in the presence of changing concentrations of salt. Isotherm and saturation type kinetic constants varied due to the level of salt were expressed as a function of initial salt concentration.
    Journal of Hazardous Materials 07/2007; 145(1-2):210-20. · 4.33 Impact Factor
  • Zümriye Aksu, Ayşe Tuğba Eren
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    ABSTRACT: The production of carotenoids by the strain of Rhodotorula glutinis, a red soil yeast isolated from IPRAŞ refinery wastewater, was investigated in a batch system as a function of initial pH, temperature, aeration rate, initial sugar (glucose, molasses sucrose and whey lactose) and ammonium sulphate concentrations and activator (cotton seed oil and Tween 80) addition. Optimum pH and temperature for total carotenoids production were determined as 6 and 30 °C, respectively. Total carotenoids concentration and carotenoids production yield significantly enhanced with increasing aeration rate up to 2.4 vvm. An initial ammonium sulphate concentration of 2 g l−1 gave the maximum carotenoids production. Only the cotton seed oil improved the carotenoids productivity of the yeast considerably at 5 g l−1 initial glucose concentration. In general, the increase in initial glucose and molasses sucrose concentrations extended the growth of yeast and total carotenoids production while increase in whey lactose concentration did not show the same effect. The highest carotenoid concentration (125.0 mg total carotenoids per liter of fermentation broth) was obtained when 20 g l−1 molasses sucrose was used as the carbon source while the highest product yield based on the maximum cell concentration (35.5 mg total carotenoids per gram of dry cells) was achieved when 13.2 g l−1 whey lactose was the carbon source in the broth.
    Biochemical Engineering Journal 07/2007; · 2.37 Impact Factor
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    ABSTRACT: A continuous fixed bed study was carried out by using dried Rhizopus arrhizus as a biosorbent for the removal of three reactive dyes; Gemacion (Procion) Red H-E7B (GR), a monoclorotriazine mono-azo type reactive dye; Gemazol Turquise Blue-G (GTB), a vinyl sulfone mono-azo type reactive dye and Gemactive (Reactive) Black HFGR (GB), a vinyl sulfone di-azo type reactive dye from aqueous solution. The effect of operating parameters such as flow rate and inlet dye concentration on the sorption characteristics of R. arrhizus was investigated at pH 2.0 and at 25 degrees C for each dye. Data confirmed that the total amount of sorbed dye decreased with increasing flow rate and increased with increasing inlet dye concentration for each dye. The column biosorption capacity of dried R. arrhizus was 1007.8 mg g(-1) for GR dye, 823.8 mg g(-1) for GTB dye and 635.7 mg g(-1) for GB dye at the highest inlet dye concentration of approximately 750 mg l(-1) and at the minimum flow rate of 0.8 ml min(-1). Thomas and Yoon-Nelson models were applied to experimental data to predict the breakthrough curves and to determine the biosorption capacity of the column for each dye useful for process design. Both models were found suitable for describing the whole dynamic behavior of the column with respect to flow rate and inlet dye concentration.
    Journal of Hazardous Materials 06/2007; 143(1-2):362-71. · 4.33 Impact Factor
  • Zümriye Aksu, Tülin Kutsal
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    ABSTRACT: Biosorption of heavy metals by microbial cells has been recognized as a potential alternative to existing technologies for removing heavy metals from industrial waste waters. Many aquatic microorganisms, such as algae, can take up dissolved metals from their surroundings to their cells. In this study, the adsorption of lead(II) ions was investigated in a single-staged batch reactor. Chlorella vulgaris, a green alga, was used as the sorbent. The sorption phenomenon was expressed by the Freundlich adsorption isotherm and this expression was used for the calculation of residual or adsorbed metal ion concentration at equilibrium (Ceq or Cx,eq) at a given ‘volume of waste water containing heavy metal ion/quantity of alga (V0/X0)’ ratio in a single-staged batch reactor. Experimental Ceq and Cx,eq values were compared to calculated ones. Applications in waste water treatment for lead(II) removal have been suggested.
    Journal of Chemical Technology & Biotechnology 04/2007; 52(1):109 - 118. · 2.50 Impact Factor
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    ABSTRACT: Many dye-bearing wastewaters also contain heavy metal ions. Although the decolorization of single reactive dye or the uptake of single heavy metal ions by various growing cells has been extensively studied, very little attention has been given to the simultaneous bioremoval of reactive dye-metal ion systems. In this study, the single and combined effects of chromium(VI) and Remazol Black B reactive dye on the chromium(VI) and dye removal properties of adapted Trametes versicolor, a white-rot fungus, was investigated in a batch system at different levels of chromium(VI) and dye. Removal studies were performed at an initial pH of 4.0. Chromium(VI) uptake studies were carried out in two different growth media; mainly containing glucose and reduced quantity of glucose and whey. As the maximum microbial chromium(VI) uptake was accomplished in glucose + whey medium, single dye and binary dye-chromium(VI) bioremoval studies were also performed in this culture medium. Although the single removal of chromium(VI) and dye was enhanced with increasing initial concentration of each component up to 30 mg l−1 for chromium(VI) and up to 400 mg l−1 for dye, in general the presence of increasing concentrations of chromium(VI) ions much more severely inhibited the dye bioremoval by T. versicolor. While single chromium(VI) uptake efficiency was 32.2% in 30 mg l−1 chromium(VI) containing growth medium and single dye removal percent was 77.0% in 400 mg l−1 dye-bearing growth medium, the fungus was only capable of 10.8 and 13.3% removals of chromium(VI) and Remazol Black B dye, respectively, in the growth medium containing the binary mixture of these components at the above concentrations.
    Enzyme and Microbial Technology 04/2007; · 2.97 Impact Factor
  • Zümriye Aksu, I. Alper Isoglu
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    ABSTRACT: In this study, simultaneous biosorption of Gemazol Turquoise Blue-G reactive dye anions and copper(II) cations to dried sugar beet pulp, an agricultural solid waste by-product, from binary mixtures was studied and compared with single dye and metal ion situation in a batch stirred system. The effects of pH and single and dual component concentrations on the equilibrium uptake of each component, both singly and in mixture were investigated. The working pH value for the biosorption of single Gemazol Turquoise Blue-G dye and single copper(II) was determined as 2.0 and 4.0, respectively. The equilibrium uptake of each component increased with increasing its initial concentration up to 750 mg l−1 for dye and up to 200 mg l−1 for copper(II) ions for both pH values. The presence of increasing concentrations of copper(II) ions increased the equilibrium uptake of dye anions while the adding of increasing concentrations of dye diminished the copper(II) ion uptake for both pH values studied. This situation showed the synergistic effect of copper(II) cations on dye biosorption and the antagonistic effect of dye anions on copper(II) biosorption. Adsorption isotherms were developed for single-dye, single copper(II) and dual-dye-copper(II) ion systems at these two pH values and expressed by the mono-component Langmuir model and multi-component synergistic and antagonistic Langmuir models and model parameters were estimated by the non-linear regression.
    Chemical Engineering Journal 03/2007; · 4.06 Impact Factor
  • Zümriye Aksu, I Alper Isoglu
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    ABSTRACT: The potential use of dried sugar beet pulp, an agricultural solid waste by-product, as an biosorbent for Gemazol turquoise blue-G, a copper-pthalocyanine reactive dye commonly used in dyeing of cotton, was investigated in the present study. Batch adsorption studies were carried out to examine the influence of various parameters such as initial pH, temperature and initial dye concentration. The results indicated that adsorption was strongly pH-dependent and slightly temperature-dependent. At 800 mg l(-1) initial Gemazol turquoise blue-G concentration, dried sugar beet pulp exhibited the highest Gemazol turquoise blue-G uptake capacity of 234.8 mg g(-1) at 25 degrees C and at an initial pH value of 2.0. The Freundlich, Langmuir, Redlich-Peterson and Langmuir-Freundlich, the two and three parameters adsorption models were used for the mathematical description of the biosorption equilibrium and isotherm constants were evaluated depending on temperature. Both the Langmuir and Redlich-Peterson models were applicable for describing the dye biosorption by dried sugar beet pulp in the concentration (100-800 mg l(-1)) and temperature (25-45 degrees C) ranges studied. Simple mass transfer and kinetic models were applied to the experimental data to examine the mechanisms of biosorption and potential rate controlling steps such as external mass transfer, intraparticle diffusion and biosorption process. The sorption process was found to be controlled by both surface and pore diffusion with surface diffusion at the earlier stages followed by pore diffusion at the later stages. Pseudo first-order, pseudo second-order and saturation type kinetic models described the biosorption kinetics accurately at all concentrations and temperatures studied. The thermodynamic analysis indicated that the sorption process was exothermic and the biosorption of dye on dried sugar beet pulp might be physical in nature.
    Journal of Hazardous Materials 10/2006; 137(1):418-30. · 4.33 Impact Factor
  • Zümriye Aksu, Ferda Gönen
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    ABSTRACT: Simultaneous biosorption of phenol and chromium(VI) ions to Mowital®B30H resin immobilized activated sludge from binary mixture was studied and compared with single phenol or chromium(VI) biosorption in a continuous packed bed column. The phenol and chromium(VI) binding capacity of biosorbent was shown as a function of single and dual pollutant concentrations at a flow rate of 0.8mlmin−1 and at a pH value of 1.0. The equilibrium uptake (or column biosorption capacity) of each pollutant was determined by evaluating the breakthrough curves obtained at different inlet concentrations changing 50–500mgl−1 in single and binary systems. The maximum column biosorption capacity of dried activated sludge was 9.0mgg−1 for phenol and 18.5mgg−1 for chromium(VI) at single ion situation. The column sorption capacity of immobilized dried activated sludge for phenol (or for chromium(VI)) decreased notably due to the presence of other component. The mono- and multi-component sorptions in packed bed were expressed by the Yoon and Nelson model to determine the kinetic constants and to predict the breakthrough curves of each component. The functional relationship between Yoon and Nelson kinetic constant of each component and concentrations of phenol and chromium(VI) in binary mixture was determined by using Response Surface Methodology.
    Separation and Purification Technology 05/2006; 49(3):205-216. · 3.07 Impact Factor

Publication Stats

5k Citations
211.16 Total Impact Points

Institutions

  • 1999–2010
    • Ankara University
      • Department of Biology
      Engüri, Ankara, Turkey
  • 1990–2010
    • Hacettepe University
      • Department of Chemical Engineering and Bioengineering Division
      Ankara, Ankara, Turkey
  • 2008
    • Mersin University
      • Department of Chemical Engineering
      Zephyrium, Mersin, Turkey
  • 2003
    • Firat University
      • Department of Environmental Engineering
      Mezreh, Elazığ, Turkey