Synthesis, Characterization and, the Heavy Metal Removal Efficiency ...

25 downloads 0 Views 1022KB Size Report
Then the heavy metal removal efficiencies and adsorption capacities of the nanoparticles ..... In: Ohgaki S, Ukushi K (eds), Proceedings of the First International.
Ekoloji 22, 89, 89-96 (2013) doi: 10.5053/ekoloji.2013.8911

RESEARCH NOTE

Synthesis, Characterization and, the Heavy Metal Removal Efficiency of MFe2O4 (M=Ni, Cu) Nanoparticles Naim SEZGIN1*, Musa SAHIN2, Arzu YALCIN1, Yuksel KOSEOGLU3,4 1 Istanbul

University, Faculty of Engineering, Department of Environmental Engineering, 34320, Avcilar, Istanbul-TURKEY 2 Istanbul

University, Faculty of Engineering, Department of Chemistry, 34320, Avcilar, Istanbul-TURKEY 3 Fatih

University, Department of Physics, Buyukcekmece 34500 Istanbul- TURKEY

4 Suleyman Demirel University, Faculty of Engineering and Natural Sciences, AlmatyKAZAKHSTAN *Corresponding

author: [email protected]

Abstract The purpose of the study described in this paper was to compare the removal of the heavy metals zinc, nickel, and copper from synthetic wastewater by using nanoparticles of CuFe2O4 and NiFe2O4. The nanoparticles of nickel and copper ferrite (CuFe2O4 and NiFe2O4) were produced by the PEG assisted hydrothermal method. The structural and morphological characterizations were determined using XRD, FT-IR, and SEM. These nanoparticles were dispersed into synthetic wastewater contaminated with zinc, nickel, and copper. Once they had bound to the heavy metals, they were removed from the water solution using a strong magnet. The metal concentrations of the filtered samples were determined by using atomic absorption spectrophotometry (AAS). Then the heavy metal removal efficiencies and adsorption capacities of the nanoparticles (CuFe2O4 and NiFe2O4) were calculated. The removal efficiencies of Cu(II), Ni(II) and Zn(II) by using CuFe2O4 nanoparticles was calculated as 83.50%, 98.85%, and 99.80%, respectively. The removal efficiencies of Cu(II), Ni(II), and Zn(II) by using NiFe2O4 nanoparticles were calculated as 92.55%, 36.56 %, and 99.91%, respectively. The measurements were repeated several times with the same sample and almost the same results were obtained each time. Keywords: Adsorption, adsorption capacity, copper ferrite, heavy metal, nanoparticles, nickel ferrite. MFe2O4 (M=Ni, Cu) Nanopartiküllerinin Sentezi, Karakterizasyonu ve Ağır Metal Giderim Verimliliği Özet Bu makalede anlatılan çalışmanın amacı sentetik atıksulardan çinko, nikel ve bakır gibi ağır metallerin giderimini CuFe2O4 ve NiFe2O4 nanopartikülleri kullanarak incelemektir. Nikel ve bakır ferrit nanopartiküller (CuFe2O4 ve NiFe2O4) PEG-destekli hidrotermal metod kullanılarak sentezlenmiştir. Nanopartiküllerin yapısal ve morfolojik karakterizasyonu için XRD, FT-IR ve SEM kullanılmıştır. Karakterize edilen nanopartiküller çinko, nikel ve bakır içeren sentetik atıksuyun içerisine bırakılmıştır. Ağır metallerin nanopartiküllerle adsorpsiyonunun ardından güçlü bir mıknatıs ile nanopartiküller atıksudan ayrılmıştır. Süzülen atıksu içerisindeki ağır metal konsantrasyonları atomik absorpsiyon spektrofotometresi (AAS) ile belirlenmiştir. Daha sonra kullanılan nanopartiküllerin (CuFe2O4 ve NiFe2O4) ağır metal giderim verimleri ile adsorpsiyon kapasiteleri hesaplanmıştır. CuFe2O4 nanopartikülünün Cu(II), Ni(II) ve Zn(II) giderim verimleri sırasıyla %83,50, %98,85 ve %99,80 olarak belirlenmiştir. NiFe2O4 nanopartikülünün Cu(II), Ni(II) ve Zn(II) giderim verimleri ise sırasıyla %92.55, %36.56 ve %99.91 olarak hesaplanmıştır. Deneyler aynı örnekle birçok kez tekrar edilmiş ve benzer sonuçlar elde edilmiştir. Anahtar Kelimeler: ağır metaller, adsorpsiyon, adsorpsiyon kapasitesi, bakır ferrit, nanopartiküller, nikel ferrit. Sezgin N, Sahin M, Yalcin A, Koseoglu Y (2013) Synthesis, Characterization and, the Heavy Metal Removal Efficiency of MFe2O4 (M=Ni, Cu) Nanoparticles. Ekoloji 22(89): 89-96.

INTRODUCTION The removal of heavy metals as a pollutant in water has been under intense research due to their

potential toxicity which causes heavier exposure for some organism and the ecology even at very low concentration. The presence of heavy metals like Received: 17.01.2013 / Accepted: 14.06.2013

No: 89, 2013

89

Ekoloji zinc, nickel, and copper may exhibit toxicity and carcinogenicity for the human body. Although zinc and copper are essential in small quantities, the excess of them is hazardous to the human body (Mishra and Patel 2009). Copper in even a low amount causes toxic effects in living cells due to the fact that copper produces oxygen species which can damage lipids, nucleic acids, and proteins (Halliwell and Gutteridge 1992). The excess of nickel may cause some health problems such as paralysis, diarrhea, low blood pressure, lung irritation, and bone defects (Kudesia 1990). The maximum concentration limits (MCL) for some hazardous heavy metals, were constituted by the USEPA and are given in Table 1 (Babel and Kurniawan 2003). What is needed is materials capable of effective adsorption. Therefore, it is also very important to develop some processes to remove heavy metals from discharged waters as a result of their release by industry, chemical plants, mining, electroplating, paints, pesticides, agriculture, combustion of fossil fuels, and traffic (Yılmaz et al. 2006, Osma et al. 2012). Various techniques currently used for heavy metal removal from discharged water are physicochemical precipitation (Meunier et al. 2006, Djedidi et al. 2009), ion exchange (Lacour et al. 2001), solvent extraction (Li and Chen et al. 2008), adsorbents (Cokadar et al. 2003, Li and Tang et al. 2008, Shahwan et al. 2010, Goren et al. 2010), reverse osmosis (Bakalar et al. 2009, Aljendeel 2011), ultrafiltration (Juang and Shiau 2000), biosorption (İleri and Cakir 2006, Senturk and Buyukgungor 2013), and electrodialysis (Dermentzis 2010) along with polymeric structures like hydrogels (Essawy and Ibrahim 2004, Sezgin 2012). While there are ways to remove heavy metals, they are expensive and require extensive hardware and high-pressure pumps that run on electricity. Nonmaterials recently have been studied for water and wastewater treatment (Köseoğlu 2010, Ozmen et al. 2010, Mahdavi et al. 2013, Mueller et al. 2013). Nanoparticulate metal oxides are among the most used nanoparticles (Nowack et al. 2007). The ferrospinels are interesting sorbents for the removal of heavy metals contaminants (Dixit and Hering 2003). Ferrospinels have the general formula of AFe2O4 (where A: Fe, Co, Ni, Zn, etc.) and the unit cell contains 32 O-atoms in cubic close packing with 8 Td (tetra-hedral) and 16 Oh (octahedral) occupied sites. When magnetic ferrospinels are made as 90

Sezgin et al. Table 1. The MCL standards for the most hazardous heavy metals.

nanoparticles, the smaller particle size and high surface area enhances its capacity for As removal (Yavuz et al. 2006). By using NiFe2O4, it obtained a 90 % removal efficiency of arsenic from wastewater (Koseoglu 2010). In a study by Ozmen at al. (2010), copper(II) was removed from water by using a modified Fe3O4. The experimental results showed that the removal efficiency of copper(II) in the presences of co-existing ions (Pb(II), Zn(II), Ni(II), Co(II), Cr(III) etc.) were in the range of 31.6-39.6 %, as a result of the competition with copper(II) for adsorption. Thus, they found that it was lower than that (75.3 %) with only the presence of copper(II) in the solution. Generally, it is known that heavy metals can be separated from nanoparticles by desorption in an inorganic acid or alkaline medium (Afkhami and Moosavi 2010, Hao et al. 2010, Tang and Lo 2013). Thus, the heavy metals are recovered and the nanoparticles can be reused many times for desorption. It should also be remembered that desorption of heavy metals from nanoparticles in strong acid or an alkaline medium may lead to nanoparticle dissolution (Yantase et al. 2007). Therefore, a weak acid medium must be used for desorption. Nanophase materials with an average grain size in the range of 1 to 50 nm have attracted research interest for more than a decade since their physical properties are quite different from that of their bulk micron-sized counterparts because of the large volume fraction of atoms that occupies the grain boundary area (Gleiter 1989, Koseoglu and Kavas 2008). The surface area of the nanostructured materials is large as the grain sizes are small. The increase in the interfacial energy due to defects, dislocations, and lattice imperfections leads to changes in various physical properties and hence one can tailor the materials with specific properties. Almost 50 % of the atoms reside in the grain boundary area when the grain size is reduced to less than 10 nm, whereas, it is only 1-3 % when the grain No: 89, 2013

Synthesis, Characterization and, the Heavy Metal Removal...

size is 100 nm (Gleiter 1989, Mutschele and Kircheim 1987). In this paper we report the synthesis of copper and nickel ferrite nanoparticles (CuFe2O4 and NiFe2O4) by using the polyethylene glycol (PEG) assisted hydrothermal method and the removal studies for zinc, copper, and nickel ions from synthetic wastewater with these spinel ferrite nanoparticles. The experiments involved suspending pure samples of uniform-sized nickel and copper ferrite nanoparticles in water. MATERIAL AND METHODS Synthesis of Nanoparticles The synthesis of the nanoparticles was done by using the PEG assisted hydrothermal method used for the synthesis of different ferrite nanoparticles (Gozuak et al. 2009, Koseoglu et al. 2011, Koseoglu et al. 2012). All the reagents used in the experiments were analytically pure and were purchased from Merck Chemicals Company, and were used without further purification. To form a clear solution 0.725g Ni(NO3)2•6H2O and 2.02g of Fe(NO3)3•9H2O were each dissolved in 10 mL of distilled water and mixed with a magnetic stirrer. These mixtures of Ni(NO3)2•6H2O and Fe(NO3)3•9H2O were successively dissolved. The reaction molar ratio of Ni and Fe has to be 1:2. After reaching the proper ratio, 20 mL of polyethylene glycol (PEG) was added to the solution and then the solution was stirred again with a magnetic stirrer until the reactants were dissolved completely, approximately 30 min. The aim of the PEG addition is to prevent an increase in the size of the nanoparticles. The pH of the solution was adjusted to 11.0 by adding 0.2 M NaOH dropwise during stirring. After continuous stirring at 400 rpm for half an hour, a homogeneous solution was obtained. Then the solution was poured in to a Teflon lined stainless autoclave. The autoclave was kept at 180°C in an oven for 24h and then cooled to room temperature naturally. The products were centrifuged and washed several times with de-ionized water, acetone, and absolute ethanol. Then the samples were put again in an oven at 70°C to dry. After drying the solid phase samples were ground in a mortar to make them powder. The obtained powders were used for all of the measurements. The same procedure was followed for the synthesis of CuFe2O4 nanoparticles by changing nickel nitrate with copper nitrate.

No: 89, 2013

Ekoloji Characterization of Nanoparticles The X-ray powder diffraction analysis was conducted with a Huber JSO-DEBYEFLEX 1001 Diffractometer (XRD) using Cu Kα (operated at 40 kV and 35 mA). The FT-IR transmission spectra were taken with a Mattson Satellite Infrared Spectrometer from 4000 to 400 cm-1. The structural and morphological characterizations of the samples were accomplished using a field emission scanning electron microscopy (FE-SEM JEOL 7001 FE). The samples were coated with carbon prior to SEM measurements. Heavy Metal Removal Experiments Here we report the synthesis of copper and nickel ferrite (CuFe2O4 and NiFe2O4) nanoparticles and the potential uses of these nanocomposites for Cu(II), Ni(II), and Zn(II) removal from the synthetic wastewater. For this purpose, we prepared the synthetic waste water by dissolving salts of Ni(NO3)2•6H2O, Cu(NO3)2•3H2O, and N2O6Zn •6H2O in distilled water by using measured amounts. An 0.1 g of nanoparticles were used and mixed with the wastewater which is a composite metal mix consisting of Cu(II), Ni(II), and Zn(II) metal ions. The concentrations of Cu(II), Ni(II), and Zn(II) in the synthetic wastewater were 18.94, 42.42, and 42.73 mg/L, respectively. The samples of 25 ml of wastewater in 100 ml schliff-erlenmeyers were prepared in two groups; 0.1 g of CuFe2O4 was added to the first group and 0.1 g of NiFe2O4 was added to the second group. The samples were mixed in a shaker (Gallenkamp orbital incubator, 25°C) at 120 rpm for 24 hours and then filtered with an 0.5 micron paper filter. The samples were then acidulated with 0.2% nitric acid. The amounts of Cu(II), Ni(II), and Zn(II) were determined by atomic absorption spectrometry (AAS) with a Varian Spectra instrument model 220 spectrometer. A standard solution containing the same matrix as the samples was made up at the appropriate concentrations for each element and used to draw a calibration curve in AAS. The removal efficiencies and adsorption capacities of nanoparticles (CuFe2O4 and NiFe2O4) were calculated using equations 1 and 2. (1)

(2)

91

Ekoloji where E (%) is the removal efficiency, q (mg/g) is adsorption capacity, C0 (mg/L) and Ce (mg/L) are the initial and equilibrated metal concentrations, respectively, V(L) is the volume of added solution, and m (g) is the mass of the adsorbent (dry). The Apparatus Used The following materials and equipment were used during the proposed validation study. Materials: Cu standard stock solution (1000 μg Cu/L), Ni standard stock solution (1000 μg Ni/L), Zn standard stock solution (1000 μg Zn/mL), Nitric acid solution(65%), and distillated water. Equipment: Varian Spectra instrument model 220 Atomic absorption spectrometer, and a Gallenkamp orbital incubator. RESULTS Structural Characterization of Nanoparticles The phase identification, of the as-prepared NiFe2O4 and CuFe2O4 samples, was determined by X-ray diffraction (XRD). Figures 1 and 2 show the XRD patterns of the as prepared samples of NiFe2O4 and CuFe2O4 and they indicate that both samples have a single spinel phase with a good crystallinity. By comparing XRD patterns of present investigations with the standard data (JCPDS: 00010-0325 for NiFe2O4 and JCPDS: 77-10 for CuFe2O4), it has been concluded that both samples can be perfectly indexed to the cubic spinel structure indicated in the reflecting planes (111), (220), (311), (222), (400), (422), (511), and (440) in the patterns. Using Scherrer's equation: D=0.9 λ / β cos θ where D is the average crystalline size, λ is the wavelength of Cu Kα, β is the full width at half maximum (FWHM) of most intense diffraction peak (311), and θ is the Bragg's angle, the average particle sizes are estimated to be around 25.6 nm for NiFe2O4 and 11.3 nm for CuFe2O4. FT-IR Spectroscopy Figure 3 shows the representative IR spectra of the as prepared ferrites of CuFe2O4 and NiFe2O4. The two main broad metal-oxygen bands are important in the IR spectra of all spinels, especially in ferrites. The highest IR band, V1, is generally observed in the higher frequency range of 600-550 cm-1, corresponding to the intrinsic stretching vibrations of the metal-oxygen bond at the tetrahedral site, Mtetra-O. The lowest IR band, V2, is usually observed in the frequency range of 450-385 cm-1, assigned to stretching vibrations of the metal92

Sezgin et al.

Fig 1. The XRD pattern for NiFe2O4 nanoparticles synthesized by the PEG assisted hydrothermal method.

Fig 2. The XRD pattern for CuFe2O4 nanoparticles synthesized by the PEG assisted hydrothermal method.

oxygen bond at the octahedral site, Mocta-O. As seen in the Figure 3, both the V1 and V2 stretching vibrations were observed with the normal mode of vibration of the tetrahedral cluster and is higher than that of the octahedral cluster. This can be attributed to the shortness of the tetrahedral bond and the length of the octahedral bond. Since both Cu2+ and Ni2+ ions preferentially occupy the octahedral sites and Fe3+ ions can occupy both octahedral and tetrahedral sites, both of the V1 and V2 bands observed are the characteristics of the prepared Cu and Ni ferrites (Koseoglu et al. 2011, Marinca et al. 2012). In the FT-IR spectra, V1 (540 cm-1) ) and V2 (427 cm-1) for CuFe2O4 shifted slightly to higher frequencies as V1 (550 cm-1)) and V2 (460 cm-1) values by replacing the Cu2+ ion with an Ni2+ ion. Slight shifts of the V1 and V2 peak positions indicate that changes due to the Ni2+ substitution has No: 89, 2013

Synthesis, Characterization and, the Heavy Metal Removal...

Fig 3. The FT-IR spectra of both adsorbents.

Fig 4. SEM pictures taken from (a) CuFe2O4 and (b) NiFe2O4 nanoparticles synthesized by PEG assisted hydrothermal method.

slightly affected the metal-oxygen force constants in the tetrahedral and octahedral sites. This can be explained by the very small difference in both the atomic mass and ionic radii of the Cu and Ni ions (Faraz et al. 2012). SEM Measurements Figure 4 shows the field emission scanning electron micro-graphs (FE-SEM) of the CuFe2O4 and NiFe2O4 nanoparticles. The SEM images show that the samples consist of spherical shaped nanoparticles with small agglomeration. As seen in the SEM pictures the nanoparticles have sizes of more than 100 nm and they are dense and distributed regularly with-in the whole area (see Fig. 4(a – b)). In addition to this, although these smaller crystallites are so closely arranged together, a clear boundary between neighboring particles can also be observed. The larger particle sizes of the nanoparticles can be attributed to the PEG coating which doesn’t count in crystallite sizes obtained from XRD since PEG is amorphous. Removal of Heavy Metals The graphs of the removal efficiencies of Cu(II), Ni(II), and Zn(II) from synthetic wastewater are

No: 89, 2013

Ekoloji shown in Fig. 5 for 0.1 g CuFe2O4 and Fig. 6 for 0.1 g NiFe2O4. The removal efficiencies of Cu(II), Ni(II), and Zn(II) by using CuFe2O4 nanoparticles are calculated as 83.50%, 98.85%, and 99.80%, respectively. It was found that the higher efficiency was obtained for the removal of Zn(II) and the lower efficiency was obtained for the removal of Cu(II) as shown in Figure 5. The removal efficiencies of Cu(II), Ni(II), and Zn(II) by using NiFe2O4 nanoparticles are calculated as 92.55%, 36.56%, and 99.91%, respectively. It was found that the higher efficiency is again in the removal of Zn(II) and the lower efficiency is in the removal of Ni(II) as shown in Figure 6. As compared with the literature, Ozmen et al. (2010) found 75.3% value for Cu(II) removal efficiency from an aqueous media with the modified Fe3O4 nanoparticles (pH of the solution 4, contact time 1 h, and the amount of adsorbent 1.25 g/L) and Mahdavi et al. (2012) found the removal efficiencies of Cd, Cu, Ni, and Pb, in which Fe3O4, ZnO, and CuO nanoparticles were used, between 9.2% and 81.5%. It is also calculated as the adsorption capacities (q) of CuFe2O4 and NiFe2O4 nanoparticles for Cu(II), Ni(II), and Zn(II). The adsorption capacities (q) are shown in Figures. 7 and 8 for CuFe2O4 and NiFe2O4, respectively. The amounts adsorbed by CuFe2O4 nanoparticles were calculated as 3.95, 10.48, and 10.66 mg/g for Cu(II), Ni(II), and Zn(II), respectively. By using NiFe2O4 nanoparticles, the adsorption amounts were found as 4.38, 3.88, and 10.67 mg/g for Cu(II), Ni(II), and Zn(II), respectively. Zn(II) has the highest value when examining the metal adsorption capacities of CuFe2O4 and NiFe2O4 nanoparticles. DISCUSSION The synthesis of copper and nickel ferrite (CuFe2O4 and NiFe2O4) nanoparticles using the PEG assisted hydrothermal method and the potential uses of these nanocomposites as adsorbent for the removal of heavy metals from synthetic wastewater was investigated. The FT-IR and XRD spectra indicated that the samples have single phase spinel structure with sizes 25.6 nm for NiFe2O4 and 11.3 nm for CuFe2O4. The SEM pictures show that the nanoparticles have spherical shapes with small agglomeration. It was seen that these spinel ferrites are very efficient for the removal of heavy metals (zinc, 93

Ekoloji

Fig 5. The removal Efficiencies (%) of Cu(II), Ni(II), and Zn(II) by using 0.1 g CuFe2O4 nanoparticles.

Sezgin et al.

Fig 7. The adsorption capacities (q) of 0.1 g CuFe2O4 nanoparticles for Cu(II), Ni(II), and Zn(II)

Fig 8. The adsorption capacities (q) of 0.1 g NiFe2O4 nanoparticles for Cu(II), Ni(II), and Zn(II) Fig 6. The removal Efficiencies (%) of Cu(II), Ni(II), and Zn(II) by using NiFe2O4 nanoparticles.

copper, and nickel) from synthetic wastewater by adsorption by magnetic nanoparticles and a subsequent simple magnetic separation process. In this paper, the removal efficiencies of Cu(II), Ni(II), and Zn(II) by using CuFe2O4 nanoparticles was calculated as 83.50 %, 98.85%, and 99.80%, respectively. It was found that the higher efficiency is for the removal of Zn(II) and the lower efficiency is for the removal of Cu(II). The removal efficiencies of Cu(II), Ni(II), and Zn(II) by using NiFe2O4 nanoparticles were calculated as 92.55%,

36.56%, and 99.91%, respectively. It was found that the higher efficiency is again for the removal of Zn(II) and the lower efficiency is for the removal of Ni(II). The results indicate that CuFe2O4 and NiFe2O4 nanoferrites synthesized by the PEG assisted hydrothermal method are useful for heavy metal removal from wastewater and they have high heavy metal removal efficiencies. ACKNOWLEDGEMENTS This work was supported ny Scientific Research Projects Coordination Unit of Istanbul University. Project number 28461

REFERENCES Afkhami A, Moosavi R (2010) Adsorptive removal of Congo red, a carcinogenic textile dye, from aqueous solutions by maghemite nanoparticles. Journal of Hazardous Materials 174: 398-403. Aljendeel HA (2011) Removal of heavy metals using reverse osmosis. Journal of Engineering 3(17): 647658. Bakalar T, Bugel M, Gajdosova L (2009) Heavy metal removal using reverse osmosis. Acta Montanistica Slovaca 14(3): 250-253. Babel S, Kurniawan TA (2003) Various treatment technologies to remove arsenic and mercury from contaminated groundwater: an overview. In: Ohgaki S, Ukushi K (eds), Proceedings of the First International Symposium on Southeast Asian Water Environment, 24–25 October 2003, Bangkok, Thailand, 433-440. Cokadar H, İleri R, Ates A, İzgi B (2003), Removal of Nickel (II) ions from aqueous solution by granulated activated carbon (GAC). Ekoloji 12(46): 38-42.

94

No: 89, 2013

Synthesis, Characterization and, the Heavy Metal Removal...

Ekoloji

Dermentzis K (2010) Removal of nickel from electroplating rinse waters using electrostatic shielding electrodialysis/electrodeionization. Journal of Hazardous Materials 173(1-3): 647-652. Dixit S, Hering JG(2003) Effects of Arsenate Reduction and Iron Oxide Transformation on Arsenic Mobility. Environmental Science and Technology 37: 4182-4189. Djedidi Z, Bouda M, Souissi MA, Cheikh RB, Mercier G, Tyagi RD, Blais JF (2009) Metals removal from soil, fly ash and sewage sludge leachates by precipitation and dewatering properties of the generated sludge. Journal of Hazardous Materials 172(2-3): 1372-1382. Essawy HA, Ibrahim HS (2004) Synthesis and characterization of poly(vinylpyrrolidone-comethylacrylate) hydrogel for removal and recovery of heavy metal ions from wastewater. Reactive and Functional Polymers 61: 421-432. Faraz A, Saqib M, Ahmad NM, Rehman FM, Usman M, Mumtaz A, Hassan MA (2012) Synthesis, Structural, and Magnetic Characterization of Mn1−xNixFe3O4 Spinel Nanoferrites. Journal of Superconductivity and Novel Magnetism 25: 91-100. Gleiter H (1989) Nanocrystalline materials. Progress in Materials Science 33: 223-315. Gözüak F, Köseoğlu Y, Baykal A, Kavas H (2009) Synthesis and characterization of CoxZn1−xFe3O4 magnetic nanoparticles via a PEG-assisted route. Journal of Magnetism and Magnetic Materials 32: 2170-2177. Halliwell B, Gutteridge JM (1992) Biologically relevant metal ion-dependent hydroxyl radical generation: An update. FEBS Letters 307: 108-112. Hao YM, Man C, Hu ZB (2010) Effective removal of Cu (II) ions from aqueous solution by aminofunctionalized magnetic nanoparticles. Journal of Hazardous Materials 184: 392-399. İleri R, Çakir G (2006), Determination of biosorption removal isotherm coefficients by matlab programme for Copper ions (Cu2+) from aqueous solution. Ekoloji 15(59): 8-17. Juang RS, Shiau RC (2000) Metal removal from aqueous solutions using chitosan-enhanced membrane filtration, Journal of Membrane Science 165: 159-167. Köseoğlu Y (2010) Superparamagnetic NiFe2O4 Nanoparticles to Remove Arsenic From Drinking Water. In: Padem H (ed), Proceedings of 10th Second International Symposium on Sustainable development, 8-9 June 2010, Sarajevo, Bosnia and Herzegovina, 439-447. Köseoğlu Y, Kavas H (2008) Size and surface effects on magnetic properties of Fe3O4 nanoparticles. Journal of Nanoscience and Nanotechnology 8: 584–590. Köseoğlu Y, Bay M, Tan M, Baykal A, Sözeri A, Topkaya R, Akdoğan N (2011) Magnetic and dielectric properties of Mn0.2Ni0.8Fe3O4 nanoparticles synthesized by PEG-assisted hydrothermal method. Journal of Nanoparticle Research 13: 2235-2244. Köseoğlu Y, Alan F, Tan M, Yilgin R, Öztürk M (2012) Low Temperature Hydrothermal Synthesis and Characterization of Mn Doped Cobalt Ferrite Nanoparticles. Ceramics International 38: 3625-3634. Kudesia VP (1990) Water Pollution. Pregatiprakashan Publications, Meerut. Lacour S, Bollinger JC, Serpaud B, Chantron P, Arcos R (2001) Removal of heavy metals in industrial wastewaters by ion-exchanger grafted textiles. Analytica Chimica Acta 428(1): 121-132. Li CW, Chen YM, Hsiao ST (2008) Compressed air-assisted solvent extraction (CASX) for metal removal. Chemosphere 71(1): 51-58. Li X, Tang Y, Cao X, Lu D, Luo F, Shao W (2008) Preparation and evaluation of orange peel cellulose adsorbents for effective removal of cadmium, zinc, cobalt and nickel, Colloids and Surfaces. Physicochemical and Engineering Aspects 317: 512–521. Mahdavi S, Jalali M, Afkhami A (2012) Removal of heavy metals from aqueous solutions using Fe3O4, ZnO, CuO nanoparticles. Journal of Nanoparticle Research 14: 846. DOI: 10.1007/s11051-012-0846-0 Mahdavi S, Jalali M, Afkhami A (2013) Heavy metals removal from aqueous solutions using TiO2, MgO ve Al2O3 nanoparticles. Chemical Engineering Communications 200: 448-470. Marinca TF, Chicinas I, Isnard O (2012) Synthesis structural and magnetic characterization of nanocrystalline CuFe2O4 as obtained by a combined method reactive milling, heat treatment and ball milling. Ceramics International 38: 1951-1957.

No: 89, 2013

95

Ekoloji

Sezgin et al.

Meunier N, Drogui P, Montane C, Hausler R, Mercier G, Blais JF (2006) Comparison between electrocoagulation anchemical precipitation for metals removal from acidic soil leachate. Journal of Hazardous Materials 137(1): 581-590. Mishra PC, Patel RK (2009) Removal of lead and zinc ions from water by low cost adsorbents. Journal of Hazardous Materials 168: 319-325. Mueller NC, Buha J, Wang J, Ulrich A, Nowack B (2013) Modeling the flows of engineered nanomaterials during waste handling. Environmental Science: Processes and Impacts 1(15): 251-259. Mütschele T, Kirchheim R (1987) Hydrojen as a probe for the average thickness of a grane boundary. Scripta Metallurgica 21: 1101-1104. Nowack B, Bucheli TD (2007) Occurrence, behavior and effects of nanoparticles in the environment. Environmental Pollution 150: 5-22. Osma E, Serin M, Leblebici Z, Aksoy A (2012) Heavy Metals Accumulation in Some Vegetables and Soils in Istanbul. Ekoloji 82: 1-8. Ozmen M, Can K, Arslan G, Tor A, Cengeloglu Y, Ersoz M (2010) Adsorption of Cu(II) from aqueous solution by using modified Fe3O4 magnetic nanoparticles. Desalination 254: 162-169. Sezgin N (2012) Investigation of Heavy Metal Removal from Industrial Sewage Sludge., PhD Thesis, Istanbul Universty, Institute of Science, Istanbul. Shahwan T, Üzüm Ç, Eroğlu AE, Lieberwirth I (2010) Synthesis and characterization of bentonite/iron nanoparticles and their application as adsorbent of cobalt ions. Applied Clay Science 47: 257-262. Senturk I, Buyukgungor H (2013) Equilibrium and Kinetic Studies on the Biosorption of 2-chlorophenol and 4-chlorophenol by Live Aspergillus niger. Ekoloji 21(88): 1-12. Tang SCN, Lo IMC (2013) Magnetic nanoparticles: Essential factors for sustainable environmental applications. Water Research 47: 2613-2632. Yantase W, Warner C, Sangvanich T, Addleman RS, Carter TG, Wiacek RJ, Fryxell GE, Timchalk C, Warner MG (2007) Removal of heavy metal from aqueous systems with thiol functionalized superparamagnetic nanoparticles. Environmental Science and Technology 41: 5114-5119. Yavuz C T, Mayo JT, Yu WW, Prakash A, Falkner JC, Yean S, Cong LH, Shipley J, Kan A, Tomson M, Natelson D, Colvin VL (2006) Low-field magnetic separation of monodisperse Fe3O4 nanocrystals. Science 314: 964-967. Yılmaz R, Sakcali S, Yarci C, Aksoy A, Ozturk M (2006) Use of Aesculus hippocastanum L. as a Biomonitor of Heavy Metal Pollution. Pakistan Journal of Botany 38(5): 1519-1527.

96

No: 89, 2013