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Öğe Application of Magnetic Nanoparticles to Residue Analysis of Organochlorine Pesticides in Water Samples by GC/MS(Aoac Int, 2012) Ozcan, Senar; Tor, Ali; Aydin, Mehmet EminThis paper describes a novel magnetic-SPE method for the determination of organochlorine pesticides (OCPs) in environmental water samples by use of Fe3O4-magnetic nanoparticles (MNPs) coated with oleic acid followed by GC/MS. The chemisorption of oleic acid onto Fe3O4-MNPs provides reusability of the developed sorbent materials several times. The effects of different parameters such as pH, desorption solvent, contact time, temperature, ionic strength, and sorbent dosage on the efficiency of magnetic-SPE were investigated. The optimized SPE method involved shaking 50 mL of water sample (pH 4) with 50 mg oleic acid coated Fe3O4-MNPs for 1 h, isolating the sorbent with an Nd-Fe-B magnet, and eluting the OCPs with methanol. An ionic strength of 0.1 M and temperature of 15 C provided the maximum extraction efficiency. The LOQs were in the range of 0.006 to 0.048 mu g/L. For three fortification levels, recoveries were in the range of 44-108%, with RSD <5%. The developed SPE method was successfully applied to real water samples, and it is viable, rapid, and easy to use for analysis of OCPs in water samples.Öğe Arsenic(V) removal from underground water by magnetic nanoparticles synthesized from waste red mud(Elsevier Science Bv, 2012) Akin, Ilker; Arslan, Gulsin; Tor, Ali; Ersoz, Mustafa; Cengeloglu, YunusIn this study waste red mud (bauxite residue) sample obtained from Seydisehir (Konya, Turkey) was evaluated for the synthesis of Fe3O4 nanoparticles (NPs) in ammonia solution that can be used to remove As(V) from both synthetic and natural underground water samples. The synthesized Fe3O4-NPs were characterized by using TEM, VSM, XRD, SAXS,TGA and FT-IR spectroscopy. The Fe3O4-NPs assumed a near-sphere shape with an average size of 9 nm. The results showed that synthesized Fe3O4-NP5 from waste red mud have satisfactory magnetic properties and As(V) sorption capacity, especially at low equilibrium arsenate concentrations. (c) 2012 Elsevier B.V. All rights reserved,Öğe Characteristics and mechanisms for highly efficient adsorption of Pb(II) from aqueous solutions by engineered vinasse biochar with cold oxygen plasma process(Elsevier Science Sa, 2022) Kazak, Omer; Tor, AliVinasse based biochar was engineered by cold oxygen plasma for different treatment time between 1 and 10 min to obtain highly efficient adsorbent for Pb(II) in the aqueous solutions. The engineered biochar with largest surface area (307 m(2)/g) and primarily microporous structure was achieved when cold oxygen plasma is processed for 3 min, providing the highest adsorption capacity (481 mg/g) derived from 500 mg/L of Pb(II) solution. For the equilibrium time (90 min) and the favorite solution pH (5.0), the best-fitting isotherm model was Langmuir isotherm one with Q(o) (714 mg/g), which is superior to those of many biochar based Pb(II) adsorbents in the literature. On the basis of XRD, XPS, FT-IR instruments and surface charge measurements, the adsorption mechanisms included ion-exchange, precipitation, electrostatic attraction, cation-pi interaction and complexation. The reusable engineered vinasse biochar has also applicability to real water samples without matrix effects.Öğe Coagulation, flocculation and chemical precipitation(Iwa Publishing, 2012) Aydin, Mehmet Emin; Lazarova, Zdravka; Tor, Ali; Ozcan, Senar[Abstract Not Availabe]Öğe Determination and speciation of trace inorganic arsenic species in water samples by using metal organic framework mixed-matrix membrane and EDXRF spectrometry(Pergamon-Elsevier Science Ltd, 2022) Aslan, Fuat; Tor, AliA facile method to selectively determine trace As(V) species in the existence of As(III) one in water samples was developed, which was based on the batch adsorption process by using a miniaturized MIL-101(Fe) mixed-matrix membrane (MOF-MMM) followed by a direct determination through energy dispersive X-ray fluorescence (EDXRF) spectrometry. The quantitative adsorption of As(V) was achieved at pH (3-6) from 30 mL sample in 120 min of equilibrium time by employing the membrane with a monolayer adsorption capacity of Qo = 1.953 mg g-1. The direct determination of As(V) adsorbed on the membrane by EDXRF spectroscopy provided a method, not only easy-to-use and operable without elution stage, but also cost effective due to low gas consumption during the analysis. With a limit of detection of 0.094 mu g L-1, analytical performance of the method, which was evaluated on fortified real water samples with three levels of As(V) (5, 10 and 50 mu g L-1), demonstrated good recoveries in the range of 98(+/- 3)-105(+/- 10)%. Furthermore, the speciation of As(III) and As(V) in the fortified real samples containing other ionic species was also successfully achieved by described approach with characteristics of simple, cheap, viable and reproducible.Öğe Effects of long-term irrigation with untreated municipal wastewater on soil properties and crop quality(Springer Heidelberg, 2015) Aydin, Mehmet Emin; Aydin, Senar; Beduk, Fatma; Tor, Ali; Tekinay, Arzu; Kolb, Marit; Bahadir, MuefitIrrigating crops with untreated wastewater leads to elevated concentrations of heavy metals both in soil and cultivated crops. The current study was designed to determine heavy metal (i.e., Pb, Cd, Cr, Cu, Ni, Zn, Hg) accumulation in Konya soils in selected nine sites irrigated with wastewater for over 40 years. Non-irrigated soil samples and soil samples irrigated with well water were taken as control samples. Transport of these pollutants to the wheat samples cultivated in the investigated site was also examined. The obtained results reveal that high alkaline properties and clay structure of Konya soil reduce the mobility of contaminants and cause accumulation in the top layer of soil. Intense effect of wastewater irrigation on soil EC was determined. The highest concentrations of Pb, Cr, Cu, Cd, Zn, Ni, and Hg in wastewater irrigated soil were 5.32, 37.1, 31.5, 11.4, 91.5, 134, and 0.34 mg kg(-1), respectively. Wastewater irrigated soils were strongly polluted by means of Cd (8.23-11.6 mg kg(-1)) and moderately to strongly polluted by means of Ni (47.7-134 mg kg(-1)), exceeding Maximum Admissible Concentrations for Trace Elements in Agricultural Soils and Sewage Sludge Regulation limit values of Turkey. Maximum concentrations found for Pb, Cr, Cu, Cd, Zn, and Ni in wastewater irrigated wheat grain were 8.44, 1.30, 9.10, n.d, 29.31, and 0.94 mg kg(-1), respectively. Besides, Hg was not detected in any samples of wheat grain. Based on the regulation of Turkish Food Codex, Pb contamination in wheat samples grown in the sampling site was evidenced.Öğe Efficient adsorption of lead (II) and copper (II) from aqueous phase using oxidized multiwalled carbon nanotubes/polypyrrole composite(Taylor & Francis Inc, 2018) Nyairo, Wilfrida Nyanduko; Eker, Yasin Ramazan; Kowenje, Chrispin; Akin, Ilker; Bingol, Haluk; Tor, Ali; Ongeri, David MokonoPolypyrrole coated oxidized multiwalled carbon nanotubes (oMWCNT/Ppy) were applied to determine the adsorption characteristics of Pb(II) and Cu(II) from their aqueous solutions. Structural and morphological characterization studies using scanning electron microscopy, thermogravimetric analysis, Fourier transform infrared and Raman spectroscopy showed successful preparation of the oMWCNT/Ppy composite. The influence of pH, contact time, and initial metal ion concentration on the adsorption of Pb(II) and Cu(II) was studied. The adsorption processes fitted well with Langmuir isotherm and pseudo-second-order kinetic models. The maximum adsorption capacities for Pb(II) and Cu(II) were determined as 26.32 and 24.39mg/g, respectively. Desorption studies indicated that the oMWCNT/Ppy composite could be reused for five cycles with minimum loss of its initial adsorption capacity.Öğe Efficient Removal of Lead(II) Ions from Aqueous Solutions Using Methyl-?-Cyclodextrin Modified Graphene Oxide(Springer, 2017) Nyairo, Wilfrida Nyanduko; Eker, Yasin Ramazan; Kowenje, Chrispin; Zor, Erhan; Bingol, Haluk; Tor, Ali; Ongeri, David MokonoGraphene oxide (GO) and graphene oxide modified with methyl-beta-cyclodextrin denoted as GO-m beta CD were prepared and applied as adsorbents to determine the adsorption characteristics of Pb(II) from aqueous solutions. The characteristic results of Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), Raman spectroscopy, and scanning electron microscopy (SEM) showed that m beta CD was successfully physically attached to GO to form the GO-m beta CD nano-composite. The adsorption equilibrium and kinetics of the adsorbents were well described by Langmuir isotherm and pseudo-second-order models, respectively. The maximum Pb(II) adsorption capacity of GO-m beta CD (at pH = 6 and room temperature) was determined as 312.5 mg/g which was significantly higher than that of GO (217.39 mg/g). This indicates that the modification of GO with m beta CD enhances the adsorption capacity of GO. The desorption studies show that the adsorbent GO-m beta CD can be used for at least five cycles with non-significant loss of its initial adsorption capacity for Pb(II) ions.Öğe Green preparation of a novel red mud@carbon composite and its application for adsorption of 2,4-dichlorophenoxyacetic acid from aqueous solution(Springer Heidelberg, 2017) Kazak, Omer; Eker, Yasin Ramazan; Akin, Ilker; Bingol, Haluk; Tor, AliThis study reports the eco-friendly preparation of a novel composite material consisting of red mud and carbon spheres, denoted as red mud@C composite, and its application for the removal of 2,4-dichlorophenoxyacetic acid herbicide (2,4-D) from aqueous solution. The preparation route has a green approach because it follows the low-energy consuming one-step hydrothermal process by using starch as a renewable carbon precursor and red mud as a waste from aluminum production industry. Characterization of the red mud@C composite was performed by FT-IR, TGA, SEM, TEM, BET, XRD, and Raman microscopy analyses. The batch adsorption studies revealed that the red mud@C composite has higher 2,4-D adsorption efficiency than those of the red mud and the naked carbon spheres. The maximum removal at initial pH of 3.0 is explained by considering the pKa of 2,4-D and pH of point of zero charge (pH(pzc)) of the composite material. The adsorption equilibrium time was 60 min, which followed the pseudo-second-order kinetic model together with intra-particle diffusion model. The isotherm analysis indicated that Freundlich isotherm model better represented the adsorption data, with isotherm parameters of k [15.849 (mg/g) (mg/L)(-1/n) ] and n (2.985). The prepared composite is reusable at least 5 cycles of adsorption-desorption with no significant decrease in the adsorption capacity.Öğe Guide to the selection of water treatment processes for removal of metals(Iwa Publishing, 2012) Bufa-Dorr, Zsuzsanna; Borsanyi, Matyas; Tor, Ali[Abstract Not Availabe]Öğe In situ preparation of magnetic hydrochar by co-hydrothermal treatment of waste vinasse with red mud and its adsorption property for Pb(II) in aqueous solution(Elsevier, 2020) Kazak, Omer; Tor, AliHerein, a new magnetic hydrochar was prepared through co-hydrothermal treatment of vinasse with red mud, two abundant industrial wastes, and its adsorption property was evaluated on Pb(II), selected model ion in aqueous solution. During co-hydrothermal process, Fe2O3 species in red mud was reduced to Fe3O4 form, hereby, in situ magnetization of hydrochar was achieved, which was confirmed by characterization studies. Produced hydrochar with porous structure (V-total = 0.071 cm(3)/g and BET surface area = 23 m(2)/g) had saturation magnetization (44.7 emu/g), providing easier separation from water by a magnet. Maximum Pb(II) adsorption was favored at pH >= 5.0 within 120 min of equilibrium time and Freundlich isotherm model was preferable. The contribution percentage of different mechanisms including cation-exchange (40.8 %), (electrostatic attraction + cation-pi interaction) (31.2 %), precipitation (25.4 %) and complexation (2.6 %) to overall Pb(II) adsorption indicated that cation-exchange was the dominant mechanism. Finally, application to fortified real water demonstrated that in situ magnetic hydrochar produced by suggested approach was successful at adsorptive removal of Pb(II) from water with no matrix effects.Öğe In-situ magnetization of porous carbon beads by pyrolysis of waste red mud doped polysulfone beads for efficient oil sorption(Elsevier Science Sa, 2020) Kazak, Omer; Eker, Yasin Ramazan; Tor, AliThis study describes for the first time the preparation of in-situ magnetic porous carbon beads (MPC beads) through simple phase inversion and subsequent pyrolysis of red mud doped polysulfone beads. Red mud, which is the main industrial waste resulted from the aluminium production, contains an important amount of Fe2O3. Characterization studies demonstrated the in-situ carbo-reduction of Fe2O3 species into magnetic Fe3O4 thanks to polysulfone carbon source, involving then the synthesis of MPC beads. Owing to hydrophobic surface and macroporous structure, the MPC beads were evaluated on the sorption of various oils, including gasoline, diesel oil, mineral oil and olive oil from water. The maximum sorption capacity of the MPC beads for examined oils were determined as olive oil (2.018 +/- 0.162 g/g)>mineral oil (1.418 +/- 0.138 g/g)> diesel oil (1.316 +/- 0.062 g/g)>gasoline (1.235 +/- 0.028 g/g). Moreover, the MPC beads were regenerable by heat treatment and there was no change in their sorption capacities in the first ten consecutive sorption-desorption cycles. Consequently, the suggested approach on the pyrolysis of waste red mud doped polysulfone beads was successful at preparing in-situ MPC beads, which can be efficiently used for oil spills clean-up from water with easier separation by a magnet.Öğe Investigation on the Levels of Heavy Metals, Polycyclic Aromatic Hydrocarbons, and Polychlorinated Biphenyls in Sewage Sludge Samples and Ecotoxicological Testing(Wiley, 2013) Ozcan, Senar; Tor, Ali; Aydin, Mehmet EminThis article reports the levels of heavy metals, polycyclic aromatic hydrocarbons (PAHs), and polychlorinated biphenyls (PCBs) in sewage sludges taken from two wastewater treatment plants (WWTPs) in Konya (Turkey) as well as their toxicity. The concentrations of heavy metals, including Cd, Cr, Cu, Ni, Pb, Zn in sludge samples from plant #2 did not exceed the limits described in both Turkish and European Union (EU) regulations. The similar result was observed in samples obtained from plant #1, except for sludge taken in May 2010. The sigma PAHs concentration ranging from 960 to 7680 mu g/kg dry matter shows that sewage sludges from plant #1 could be used for agricultural purpose. However, sewage sludges from plant #2 (sigma PAHs: 107717509 mu g/kg dry matter) was not suitable for using in agriculture. The concentrations of sigma PCBs in all investigated sludges from plant #1 (7.46709.36 mu g/kg dry matter) and plant #2 (14.12788.47 mu g/kg dry matter) were lower than the limits reported in Turkish and EU regulations. The probable sources of PAHs and PCBs in sludges were also determined. The ecotoxicological tests examined on Vibrio fischeri and Lepidium sativum organisms showed that sludges from plant #1 had no significant toxic effect, while sludges from plant #2 had acute toxic property. Finally, all the results showed that sewage sludges from plant #1 had potential for being used in agriculture.Öğe Levels of Organochlorine Pesticides and Heavy Metals in Surface Waters of Konya Closed Basin, Turkey(Hindawi Ltd, 2013) Aydin, Mehmet Emin; Ozcan, Senar; Beduk, Fatma; Tor, AliThe concentrations of organochlorine pesticides (OCPs), including alpha-, beta-, gamma-, and delta-hexachlorocyclohexane (HCH), heptachlor, heptachlor epoxide, dieldrin, aldrin, endrin, endrin aldehyde, endrin ketone, endosulfan I, endosulfan II, endosulfan sulfate, p,p'-DDE, p,p'-DDD, p,p'-DDT, methoxychlor, chlordane I, chlordane II, and heavy metals, such as As, Cr, Cu, Fe, Mn, and Ni in surface water samples from the Konya closed basin were determined to evaluate the level of contamination. Among all HCH isomers, beta-HCH is the main isomer with a concentration range of 0.015-0.065 mu g/L. DDE, DDD, and DDT were almost determined in all samples, in which DDE isomer had the highest concentration ranged from not detected to 0.037 mu g/L. In all studied OCPs, aldrin showed the highest concentration at 0.220 mu g/L. The concentrations of heavy metals in water samples were observed with order: Mn < Cu < Ni < As < Cr < Fe. In some samples, As, Fe, and Cr concentrations exceeded the drinking water quality recommended by EU, US EPA, WHO, and Turkish Regulation, while Cu, Ni, and Mn concentrations are below the guideline values. The levels of both OCPs and heavy metals were also compared with other previously published data.Öğe Novel preparation of activated carbon by cold oxygen plasma treatment combined with pyrolysis(Elsevier Science Sa, 2017) Kazak, Omer; Eker, Yasin Ramazan; Bingol, Haluk; Tor, AliThis study reports an original approach based on the inserting of a cold oxygen plasma treatment as oxidation stage between two pyrolysis processes for the preparation of an activated carbon from vinasse as a waste from the distillation of fermented sugar beet. The effects of pyrolysis temperature and plasma application time on the structural and morphological properties of the prepared carbon materials were investigated by Thermal Gravimetric Analysis (TGA), Fourier Transform Infrared Spectroscopy (FT-IR), Raman Spectroscopy, Scanning Electron Microscopy-Energy Dispersive X-ray Spectroscopy (SEM-EDX) techniques and gas adsorption measurements (BET). The results of the different conditions indicated that the structure properties of the obtained activated carbon were significantly dependent on the pyrolysis temperature. As an optimum condition, the application of oxygen plasma for 5 min between pyrolysis processes at 1000 C-omicron provided an eligible activated carbon with surface area (832.3 m(2)/g) and mainly microporous structure. After preliminary examinations on various dyes, the adsorption performance of the activated carbon with highest surface area was specifically evaluated using methylene blue as a model dye in aqueous solution as functions of various operating parameters. Langmuir adsorption capacity (909.091 mg/g) of the prepared activated carbon toward methylene blue was superior than most of the other adsorbents. (C) 2017 Elsevier B.V. All rights reserved.Öğe A novel red mud@sucrose based carbon composite: Preparation, characterization and its adsorption performance toward methylene blue in aqueous solution(Elsevier Sci Ltd, 2017) Kazak, Omer; Eker, Yasin Ramazan; Akin, Ilker; Bingol, Haluk; Tor, AliA novel carbonaceous composite material containing red mud and sucrose based carbon spheres, named as RM@ C composite, has been prepared via one-step hydrothermal carbonization (HTC) process. The prepared RM@ C composite is an environmentally friendly material because it utilized the red mud, a waste emerged from aluminium manufacturing, and sucrose, a renewable carbon precursor, in the one-step HTC process. After characterization of the composite material by XRD, FT-IR, TGA and SEM-EDX techniques, and specific surface area, pore size distribution and pH of zero point of charge (pHzpc) measurements, its batch adsorption performance was examined on the methylene blue in aqueous solution. The effective adsorption was achieved at pH = 11. At pH 11, the adsorption performance of RM@ C was superior to both red mud and naked carbon spheres. Kinetic analysis revealed that adsorption equilibrium is attained in 60 min and it is governed by the pseudo-second-order kinetic model together with intra-particle diffusion model. On the basis of isotherm analysis, Langmuir isotherm model better expressed the experimental data than Freundlich model. The Langmuir adsorption capacity of the composite material toward methylene blue was determined as 76.92 mg/g. The adsorption of methylene blue gradually decreased with increasing the ionic strength of the solution. The RM@ C composite can be reused at least five cycles of adsorption-desorption without significant changes in the adsorption efficiency.Öğe Preparation and characterization of novel polysulfone-red mud composite capsules for the removal of fluoride from aqueous solutions(Royal Soc Chemistry, 2016) Kazak, Omer; Tor, Ali; Akin, Ilker; Arslan, GulsinThis study is the first investigation on the encapsulation of red mud by a polysulfone matrix through a phase inversion process to obtain composite capsules for the removal of fluoride from aqueous solutions. This approach facilitates the use of red mud in batch and column sorption techniques because the polysulfone matrix renders efficient aqueous diffusivity. The produced polysulfone-red mud composite capsules (red mud@ PSF capsules) were characterized by using FT-IR, TGA, SEM and BET. The batch sorption experiments showed that the red mud@ PSF capsules prepared with a mass ratio of red mud to polysulfone (1 : 1, g : g) provided maximum removal at equilibrium pH between 3.2 and 4.7. The batch equilibrium was attained within 30 minutes and sorption behavior was governed by pseudo-second-order kinetics together with intra-particle diffusion. Isotherm analyses showed that the Freundlich and Redlich-Peterson isotherm models better represented the sorption data, which was confirmed by the Chi-square (chi(2)) statistical test. The capsules could be reused for at least two sorption-desorption cycles without significant change in their sorption efficiency. Batch and column experiments on a real mineral water sample fortified with fluoride (final concentration 10 mg L-1) showed that the red mud@ PSF capsules could be applied to real water samples to reduce the fluoride concentration below the limit value (1.5 mg L-1) recommended by the World Health Organization (WHO) for drinking water.Öğe Preparation of activated carbon from molasses-to-ethanol process waste vinasse and its performance as adsorbent material(Elsevier Sci Ltd, 2017) Kazak, Omer; Eker, Yasin Ramazan; Bingol, Haluk; Tor, AliHerein, the preparation of activated carbon from waste vinasse by using hydrothermal H2O2 oxidation combined with a two-step pyrolysis process has been described for the first time as a new utilization approach for the waste vinasse. The characterization studies were performed by TGA, FT-IR, Raman spectroscopy, SEM-EDX and gas adsorption measurements. The approach generated a microporous activated carbon with high specific surface area ( 989 m(2)/g) from waste vinasse. After simple experiments on various dye solutions, adsorption performance of the activated carbon was specifically studied on the methylene blue solution as functions of solution pH, contact time, adsorbent amount and reusability. The obtained activated carbon had a higher Langmuir adsorption capacity towards methylene blue ( 909.091 +/- 31.900 mg/g) than many other adsorbents and it is reusable for at least six cycles. The adsorption performance of the obtained activated carbon was also evaluated using both simulated and real dyehouse effluents. (C) 2017 Elsevier Ltd. All rights reserved.Öğe Preparation of chemically-activated high surface area carbon from waste vinasse and its efficiency as adsorbent material(Elsevier, 2018) Kazak, Omer; Eker, Yasin Ramazan; Bingol, Haluk; Tor, AliHerein, a chemically activated carbon (AC) has been prepared from molasses-to-ethanol-process waste (vinasse). The procedure involves the preparation of carbonaceous spheres (CS) from the hydrothermal carbonization of the vinasse followed by activation with KOH at 800 degrees C. The effects of sole thermal treatment (without KOH) and the chemical activation on the structure and morphology of CS were evaluated by means of TGA, FT-IR, XPS, Raman spectroscopy, SEM and BET techniques. The sole thermal treatment produced a carbonaceous material with equal micro-mesoporous contents and a specific surface area (189 m(2)/g). On the other hand, the KOH-based activation produced a mainly microporous AC (V-micro = 0.574 cm(3)/g, V-total = 0.691 cm(3)/g, V-micro/V-total = 0.83) with a high specific surface area (1042 m(2)/g). Batch adsorption efficiency of AC was determined by using Victoria Blue B as a model dye in aqueous solution as functions of several operation parameters. Based on the non-linear regression analysis, the Langmuir isotherm model with monolayer adsorption capacity of 713.254 mg/g was preferable. The obtained AC was reusable for at least five cycles of adsorption-desorption. All results showed that the prepared AC has potential usability for the treatment of water polluted by dye-stuffs. (C) 2018 Elsevier B.V. All rights reserved.Öğe Preparation of new polysulfone capsules containing Cyanex 272 and their properties for Co(II) removal from aqueous solution(Elsevier Sci Ltd, 2015) Kazak, Omer; Tor, Ali; Akin, Ilker; Arslan, GulsinIn this study, new polysulfone capsules containing Cyanex 272 (Cyanex 272@PSF capsules) were prepared by phase inversion technique for the sorption of Co(II) from aqueous solution. The characterization of the Cyanex 272@PSF capsules which were performed by using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and thermal gravimetric analysis (TGA) indicated that Cyanex 272 was successfully encapsulated by polysulfone. For the Cyanex 272@PSF capsules having the highest sorption efficiency, the encapsulation efficiency was determined as 7.2%. The batch sorption experiments showed that removal of Co(II) from aqueous solutions occurred through the cation-exchange and chelation mechanisms and maximum removal was achieved at an initial pH of 8.0 (final pH of 5.9). The Cyanex 272@PSF capsules produced with dispersed phase containing 2.0% of Cyanex 272 (by wt.) provided the highest Co(II) removal. The sorption equilibrium time was attained within 120 min. By confirming the non-linear Chi-square (x(2)) statistical test, Langmuir isotherm model was the best fit model. Langmuir sorption capacity (Q(o)) and sorption constant (b) were 2.014 mg/g and 0.281 L/mg, respectively. The regenerated capsules could be used three times with no change in their sorption capacities. Based on the experiments performed at initial pH of 8.0 for other metal ions, including Ni(II), Pb(II) and Cd(II), sorption ability of Cyanex 272@PSF capsules was in the order: Co(II) approximate to Ni(II)>Cd(II)>Pb( II). Consequently, Cyanex 272@PSF capsules have potential for removing Co(II) from aqueous solutions. (C) 2015 Elsevier Ltd. All rights reserved.
