ANALYTICAL LETTERS

Vol. 36, No. 3, pp. 641–658, 2003

SEPARATIONS

Preparation of a Chelating Resin by Immobilizing

1-(2-Pyridylazo) 2-Naphtol on Amberlite

XAD-16 and Its Application of Solid Phase

Extraction of Ni(II), Cd(II), Co(II), Cu(II),

Pb(II), and Cr(III) in Natural Water Samples

Ibrahim Narin,1 Mustafa Soylak,2,* Kadriye Kayakirilmaz,1

Latif Elci,3 and Mehmet Dogan4

1Nigde University, Faculty of Art and Science,Department of Chemistry, Nigde, Turkey

2Erciyes University, Faculty of Art and Science,

Department of Chemistry, Kayseri, Turkey3Pamukkale University, Faculty of Art and Science,

Department of Chemistry, Denizli, Turkey4Hacettepe University, Faculty of Science, Department

of Chemistry, Ankara, Turkey

*Correspondence: Mustafa Soylak, Erciyes University, Faculty of Art andScience, Department of Chemistry, 38039 Kayseri, Turkey; Fax:þ903524374933; E-mail: soylak@erciyes.edu.tr.

641

DOI: 10.1081/AL-120018254 0003-2719 (Print); 1532-236X (Online)

Copyright & 2003 by Marcel Dekker, Inc. www.dekker.com

ABSTRACT

A polystyrene divinylbenzene resin (Amberlite XAD-16) functiona-lized by 1-(2-pyridylazo) 2-naphtol has been synthesized and its

sorption properties have been investigated for preconcentration ofNi(II), Cd(II), Co(II), Cu(II), Pb(II) and Cr(III) in natural watersamples. The new resin (XAD-16-PAN) was characterized by

thermogravimetric analysis and infrared spectrometry. The analyticalparameters including pH, sample volume etc. for the quantitativerecoveries of the analyte ions using XAD-16-PAN resin were inves-

tigated. The effects of alkaline, earth alkaline ions and some anionson the sorption of analyte ions were also examined. The recoveryvalues were greater than 95% and the preconcentration factor was200 for all analyte ions. The relative standard deviations of the deter-

minations by flame atomic absorption spectrometry were less than8%. The detection limits of the analyte ions (k¼ 3, N¼ 21) werevarying from 0.056mg/L for Cd to 0.268mg/L for Cr.

Key Words: Chelating Resin; Preconcentration; XAD-16-PAN;Natural Waters; AAS.

INTRODUCTION

Separation and preconcentration techniques such as coprecipitation,electrodeposition, solvent extraction, cloud point extraction, membranefiltration, solid phase extraction[1–5] for the trace heavy metal ions arean important part of modern analytical chemistry. The most commontechnique available for the separation/preconcentration of metals fromaqueous samples is solid phase extraction method using adsorbentssuch as sephiolite, thiol cotton, activated carbon, green tea leaves,microcrystalline naphthalene, cellulose, and Diaion HP-20.[6–11]

The syntheses of chelating resins from the commercial adsorptionresins has been popular in the last decade.[12–18] In particular, studieson the synthesis of resins by the reaction of a commercial resin and asuitable chelating agent and sorption characterization of chelating resinavailable for interesting metal ions have been extensively carried out ina number of analytical laboratories because both their sorption capacitiesand sorption selectivity are superior to those of ion exchangers intrace levels. For that purpose, especially Amberlite XAD copolymershave been widely used.[19–24] Saxena and co-workers[19] have usedAmberlite XAD-2-Alizarin Red-S chelating resin for the preconcentra-tion of lead(II), cadmium(II), zinc(II) and nickel(II). In another study,

642 Narin et al.

Pyrocatechol Violet immobilized Amberlite XAD-2 resin has been syn-thesized by Saxena and Singh[20] and its adsorption characters has beenidentified. Dev et al.[15] established a new method for the sorption beha-vior of lanthanum(III), neodymium(III), terbium(III), thorium(IV) anduranium(VI) onAmberlite XAD-4 resin functionalizedwith bicine ligands.

Amberlite XAD-16 is a polystyrene divinylbenzene copolymer. It hasno ionizable functional groups. It has been used for the preconcentrationand separation of trace heavy metal ions from various media includingnatural waters, urine, dialysis concentrate, etc., by our group.[26–31] It isused as a solid matrix for synthesis of chelating resin and separation oforganic materials which has hydrophobic properties. The preparation ofnew chelating resins by using Amberlite XAD-16 and some chelatingagents have been performed by some researchers.[32–34] Lee and co-work-ers[32,33] synthesized a new chelating resin by using Amberlite XAD-16and 4-(2-thiazolylazo) resorcinol. They investigated the adsorption prop-erties of the new resin. Lee and co-workers[33,34] synthesized two differentchelating resins by using 4-(2-thiazolylazo) resorcinol and 1-(2-thiazoly-lazo)-2-naphthol as chelating agent and XAD-16 as support for thepreconcentration of trace metal ions including uranium.

1-(2-pyridylazo) 2-naphtol (PAN) is a reagent for the spectrophoto-metric determination of lots of transition metal ions.[35,36] It acts as aterdendate ligand complexing with metals through the hydroxyl oxygenatom, pyridine nitrogen atom and one of the azo group nitrogenatoms.[35,36] This point is an important advantage of PAN. It has beenalso used for the separation and preconcentration of trace heavy metals invarious media. According to our knowledge, up to now, no systematicinvestigation on the preparation of chelating resin by combination ofAmberlite XAD-16 and 1-(2-pyridylazo) 2-naphtol (PAN), the adsorptioncharacteristics and its application in trace analysis have been performed.

In the present work, a chelating resin was synthesized by immobiliz-ing 1-(2-pyridylazo) 2-naphtol (PAN) on Amberlite XAD-16 (XAD-16-PAN) and characterized. Its application of preconcentration of somemetal ions in natural water samples was performed. The optimal analy-tical conditions including pH, resin amounts, flow rates of sample andelution solutions and matrix effects were also investigated.

EXPERIMENTAL

Apparatus

Shimadzu 6501F AAS flame atomic absorption spectrometerwas employed for determination of metal ions. Atomic absorption

Chelating Resin Preparation 643

measurements were carried out in air/acetylene flame. The operatingparameters for working elements were set of these recommended by themanufacturer. The nebulizer uptake rate was adjusted to give theoptimum response for conventional sample introduction, the resultingrate being 6.0mL/min. An acetylene flow rate of 2.5 L/min was usedwith an airflow rate of 8.0 L/min.

Thermo-gravimetric analysis was performed on a Shimadzu DT-40model equipped with DTA and TG units. IR spectra were recorded ona Jasco 300 FTIR spectrometer. A mechanical shaker was used for batchexperiments.

Reagents

All solutions were prepared with deionized water. Unless otherwisestated analytical-grade acetone, acids and other chemicals used in thisstudy, were obtained from Merck, Darmstadt, Germany. Stock solutionsof all metals, containing 1000mg/L (Merck, Darmstadt) were used forpreparation of the standards for the calibration curve. The calibrationstandards were not submitted to the preconcentration procedure.

The range of the calibration standards for Ni(II), Cd(II), Co(II),Cu(II), Pb(II), and Cr(III) on flame atomic absorption spectrometricdeterminations were 0.5–10.0, 0.02–2.0, 0.2–5.0, 0.5–10.0, 1.0–20.0, and0.5–10.0mg/L, respectively. The correlation coefficient of the calibrationcurves were generally 0.999.

Ammonium acetate buffer solutions (0.1M) were prepared by addingan appropriate amount of acetic acid (Merck, Darmstadt) to ammoniumacetate solutions for pH 2–6 and ammonium chloride buffer solutions(0.1M) were prepared by adding an appropriate amount of ammonia(Merck, Darmstadt) to ammonium chloride solutions for pH 8–10.

1-(2-pyridylazo) 2-naphtol (PAN) was purchased from SigmaChem. Co., St. Louis. Amberlite XAD-16 resin (Sigma Chem. Co.) waspurchased as 20–40 mesh (specific area: 750m2/g).

Synthesis of Chelating Resin

The procedure given by Saxena et al.[19] with some little modifica-tions was applied to the synthesis of the XAD-16-PAN chelating resin.10.0 g of Amberlite XAD-16 was treated with a nitrating mixture,containing 20mL of concentrated nitric acid and 50mL of concentratedsulfuric acid and stirred for 1 h at 60�C on a water-bath. The nitrated

644 Narin et al.

mixture was poured into ice-cold water. It was further filtered, washedrepeatedly with distilled water until free from acid. Then it was reducedwith SnCl2 (40 g), concentrated hydrochloric acid (45mL), and ethanol(60mL), and refluxed for 12 h at 40�C. The amino polymer was filteredoff and washed with mixture of HCl-ethanol, water, and 2M NaOH so asto get the free amino polymer.

The amino polymer was treated with 100mL of 2M HCl for 30min,washed with distilled water in order to remove excess of HCl, suspendedin 250mL of ice cold water and mixed with 1M HCl and 1M NaNO2

in aliquots of 2.0mL each time with constant stirring. The diazotizedresin was filtered and washed with ice-cold water. It was reactedwith 1-(2-pyridylazo) 2-naphtol (2.0 g taken in 100mL solution inwater/ethanol mixture) at room temperature for 1 h. The resulting resinwas filtered and washed with distilled water. The formula of XAD-16-PAN resin is given in Fig. 1.

Column Preparation

The glass column, having a stopcock and a porous disk, was 10 cmlong, and 1.0 cm in diameter. A small amount of glass wool was placedon the disc to prevent disturbing of the XAD-16-PAN resin beadsduring sample loading. Then, 600mg of XAD-16-PAN chelating resinwas slurried in water, and then poured into the column. The bed heightof resin in the column was approximately 20mm. It was washed succes-sively with water, acetone, and water, respectively, then conditionedwith 10–15mL of buffer of pH 9. After each use, the resin in the

Figure 1. Formula of new chelating resin.

Chelating Resin Preparation 645

column was washed with large volumes of water and stored in water forthe next experiment.

Preconcentration Procedure

The XAD-16-PAN column method was tested with model solutionsprior to the determination of trace metal ions in seawater samples.For the metal determinations 100mL of solution containing 10–20 mg ofthe metal ions was added to 10mL of buffer solution (desired pH between1 and 11). The column was preconditioned by passing buffer solution.The buffered metal solution was passed over the column at a flow rateof 4mL/min by the aid of a vacuum aspirator. After passing of this solu-tion, the column was rinsed twice with 10mL of water. The adsorbedmetals on the column were eluted with 8–10mL portion of 2M HClin acetone. The eluent was evaporated over a hot plate to near dryness.The residue is dissolved with 5mL of 1.0M HCl. The eluent was analyzedfor the determinations of metal concentrations by flame AAS.

Analysis of Water Samples

The water samples were collected in prewashed (with detergent,doubly de-ionised distilled water, dilute HNO3 and doubly deioniseddistilled water respectively) polyethylene bottles. The samples werefiltered through a Millipore cellulose nitrate membrane of pore size0.45 mm. The samples were stored in 1L polyethylene bottles and acid-ified to 1% with nitric acid and were subsequently stored at 4�C ina refrigerator.[37,38]

For application of the method, 1000mL of water sample was takenin a beaker, then the pH of the sample was adjusted to pH 9 with ammo-nia/ammonium buffer solution. The separation/preconcentration methodgiven above was applied. The concentrations of the investigated analyteions in the final solution were determined by flame AAS.

RESULTS AND DISCUSSION

Characteristics of XAD-16-PAN Chelating Resin

The thermogravimetric analysis (TGA) curve of the XAD-16-PANchelating resin shows two steps. In the first step, a mass loss of 2.02%

646 Narin et al.

up to 121.2�C is due to adsorbed water on the resin. In the second stepmass loss is 6.75% up to 346.6�C. These situations agree with the pre-vious studies.[19–21,24,25] When the infrared spectra Amberlite XAD-16and XAD-16-PAN resins were compared, in the chelating resin twoadditional bands at 1629 and 3450 cm�1 that may be assigned to azo(–N¼N–) and phenolic O–H stretching vibrations. These results alsoagree with the previous studies.[19–21,24,25]

Six mini columns containing 600mg of XAD-16-PAN resin foreach investigated ions were prepared and saturated with each metalions, separately in the optimal conditions. The columns were washedwith buffer solution and water, respectively, and then the saturatedresins were dried on air. Their IR spectra were recorded and comparedwith IR spectra of XAD-16-PAN resin. The band (1629 cm�1) due to azogroup undergoes a red shift of 8–15 cm�1 when a metal ion was adsorbedon the XAD-16-PAN resin. This suggests that the coordination of themetal ions with azo group is very much responsible for their sorptiononto the XAD-16-PAN resin.

Effects of pH on the Retentions

The influence of pH on the retentions of Ni(II), Cd(II), Co(II),Cu(II), Pb(II) and Cr(III) on the XAD-16-PAN resin were investigatedin the pH range of 2–11. For this purpose column experiments wereperformed by using 50–60mL of test solutions containing 10–20 mg ofeach analyte ions. The pHs of the model solutions were adjusted by usingbuffer solutions given in the experimental section. The results aredepicted in Fig. 2. The investigated ions were quantitatively (>95%)recovered for all metal ions in the pH range of 9–11 except copper.The recoveries of copper were quantitative in the pH range of 8–11.The volume of the buffer solution had no effect. In all further studies,10mL ammonium chloride buffer solution for pH 9 was used.

The model studies at pH 9 and 10 were also repeated by adjusting thepH of the solutions with 1M NaOH. While at pH 9, cobalt and copperwere quantitatively recovered with 1M NaOH, quantitative values wereobtained at pH 10 for cadmium, cobalt, copper and lead.

Influences of Eluent Type and Eluent Volume

The effects of eluent type are an important factor in the solidphase extraction studies. The effects of 10mL of various eluents on the

Chelating Resin Preparation 647

recoveries were studied. The results are given in Table 1. The quantitativerecoveries of Ni, Cd, Co, Cu, Pb, and Cr were obtained for all analyteions by using 2M HCl in acetone as an eluent. However selective recov-eries of metal ions were also possible. For example 1M HCl was usedas eluent for nickel, cobalt and lead quantitatively separated from otheranalyte ions. Also Ni, Co and Cu ions were quantitatively recovered by1M HNO3 as eluent.

The effects of volume of 2M HCl in acetone as an eluent werealso investigated in the range of 5–10mL. Quantitative recovery values(>95 %) for analytes were obtained after 6.0mL of 2M HCl in acetone.In all further studies, 7.0mL of 2M HCl in acetone was used as eluent.

Effects of Resin Amount

The influences of the amount of XAD-16-PAN resin on themini column were also investigated in the range of 300–700mg (Fig. 3).The recovery values for the investigated ions were not quantitativetill 500mg of the resin. With more than 500mg of XAD-16-PAN resinquantitative recovery values obtained. In all subsequent studies 600mgof XAD-16-PAN resin was used.

Figure 2. Effects of pH on the retentions of analyte ions on XAD-16-PAN resin(N¼ 4, eluent: 2M HCl in acetone).

648 Narin et al.

Figure 3. Effects of resin amounts on the recoveries of investigated ions (N¼ 4,eluent: 2M HCl in acetone).

Table 1. Influences of various eluents on the recoveries of analyte ions from the

XAD-16-PAN column (N:4, eluent volume: 10mL).

Recovery (%)

Eluent type Ni Cd Co Cu Pb Cr

1M HNO3 101� 2 87� 2 93� 3 94� 2 78� 4 88� 3

2M HNO3 69� 3 72� 2 68� 3 84� 2 73� 3 73� 11M HNO3 in acetone 87� 2 92� 3 102� 2 99� 3 95� 2 103� 12M HNO3 in acetone 90� 2 80� 3 86� 2 84� 3 82� 3 77� 31M HCl 100� 2 77� 2 98� 2 60� 3 101� 2 88� 4

2M HCl 89� 3 67� 2 94� 2 92� 3 103� 2 77� 31M HCl in acetone 103� 2 89� 2 100� 3 104� 2 101� 3 85� 22M HCl in acetone 101� 2 95� 2 101� 3 98� 2 103� 2 95� 2

1M NH3 <10 <10 <10 17� 2 <10 <102M NH3 <10 <10 <10 16� 2 <10 <101M NH3 in acetone <10 <10 13� 1 21� 2 11� 2 <10

2M NH3 in acetone <10 <10 <10 18� 3 <10 <10

Chelating Resin Preparation 649

Reuse of Chelating Resin

The stability and regeneration of the XAD-16-PAN resin werealso examined. The column can be reused after regeneration with10mL 2M HCl in acetone and 10mL distilled water, respectively,and is relatively stable up to 40 runs without appreciable loss ofsorption capacity.

Effect of Sample Volume on the Recoveries

In order to explore the possibility of enriching low concentrationsof the analyte ions from the large sample volume, the influences ofthe sample volume on the recovery of the metal ions were also investi-gated. The metal amounts were 10–20 mg and in the model solution,the metal amounts were held constant while increasing the samplevolume. The effect of sample volume on the sorption of metal ionswas also investigated by passing 50–1200mL volumes through theXAD-16-PAN column. The results are depicted in Fig. 4. The adsorptionof the metal ions with 600mg resin was not affected by sample volumetill 1000mL. The highest preconcentration factor was 200 for analyteions when final volume was 5.0mL.

Figure 4. Influences of sample volume on the recoveries of analyte ions (N¼ 4,eluent: 2M HCl in acetone).

650 Narin et al.

Flow Rates of Sample and Eluent Solutions

Sample and eluent flow rates are important parameters to obtainquantitative retention and elution of analyte ions, respectively. Theinfluences of the flow rates were investigated in the range of1–10mL/min. The retentions for the analyte ions on XAD-16-PANwere virtually quantitative for sample flow rates up to 4mL/min.Variation of the elution flow rate in the range of 1.0–4.0mL/min hasno effect on the elution efficiency. In consequence, 4mL/min wasselected as flow rate for sample loading and sample elution from theXAD-16-PAN resin.

Capacity of XAD-16-PAN Resin

In order to study the adsorptive capacity of XAD-16-PAN resin, thebatch method was used. To 1.0 g resin was added 50mL of solutioncontaining 10mg of analyte ion at pH 9. After shaking for 1 h, themixture was filtered. 10mL of the supernatant solution was dilutedto 100mL and determined by flame atomic absorption spectrometry.This procedure was repeated for each analyte ions. The capacity ofsorbent for Ni(II), Cd(II), Co(II), Cu(II), Pb(II), and Cr(III) was found4.7, 4.9, 4.7, 5.0, 4.8, and 5.0mg metal/g XAD-16-PAN.

Effects of Some Cations and Anions

In order to evaluate the possibility of selective recovery of Ni(II),Cd(II), Co(II), Cu(II), Pb(II), and Cr(III) on XAD-16-PAN resin in thepresence of some cations and anions in the natural water samples,the procedure has been performed with 100mL solutions containingthese ions. The results are given in Table 2. Quantitative recoverieswere obtained for analyte ions, while lower values were found for Ca,Mg, K and Na. It can be mentioned that the low ion recoveries for theseions are helpful in the determination of heavy metals at trace levels innatural waters. These results are desired in view of applications to naturalwater samples.

The recoveries of Ca, Mg, K, and Na were determined by flameAAS and approximately found to be less than 1%. The salt contents inthe eluent solutions were found to be significantly lower and suitable forflame atomic absorption spectrometric determination.

Chelating Resin Preparation 651

Table

2.

Effects

ofmatrix

ions(N

¼5).

Ion

(added

as)

Concentration

(mg/L

)Concentration

inth

eeluen

t(m

g/L

)

Recovery(%

)

Ni

Cd

Co

Cu

Pb

Cr

——

—100�

295�

295�

199�

399�

298�

1Naþ

(NaCl)

2000

24

102�

295�

195�

1103�

2103�

3100�

21000

12

102�

297�

295�

2100�

298�

398�

3

500

10

99�

398�

397�

299�

2102�

197�

2

Kþ

(KCl)

1000

7101�

396�

2102�

496�

199�

298�

2500

597�

297�

296�

298�

298�

298�

2

Mg2þ

(MgCl 2)

1000

17

99�

197�

198�

298�

2103�

194�

3500

14

96�

298�

297�

296�

2102�

298�

2

Ca2þ

(CaCl 2)

250

39

95�

195�

296�

2103�

296�

298�

1

100

24

98�

396�

2101�

3101�

295�

195�

2

Cl�

(NH

4Cl)

1000

—100�

3100�

295�

1101�

396�

296�

2500

—102�

296�

296�

298�

199�

198�

2250

—102�

296�

298�

2100�

295�

298�

1

SO

2�

4(N

H4) 2SO

4)

500

—99�

295�

298�

1100�

394�

196�

2

250

—97�

198�

298�

298�

296�

198�

1

652 Narin et al.

Detection Limits

The detection limits of the investigated metal ions based on threetimes the standard deviations of the blank (k¼ 3, N¼ 21) on a samplevolume 100mL for Ni, Cd, Co, Cu, Pb, and Cr were 0.161, 0.056, 0.072,0.079, 0.121, and 0.268 mg/L, respectively. The detection limits of theanalyte ions can be decreased by one order of magnitude by increasingthe sample volume.

Accuracy of the Results

In order to estimate the accuracy of the procedure, different amountsof investigated ions were added to 500mL of drinking water samplescollected from Nigde University and Erciyes University and the resultingsolutions were submitted to the preconcentration procedure given inExperimental. The results are shown in Table 3. A good agreementwas obtained between the added and measured analyte amounts.The recovery values calculated for the added standards were always

Table 3. Recovery of Cu, Cd, Ni and Pb from tap water samples (N¼ 6, samplevolume: 500mL, final volume: 5mL).

Tap water samples from

Erciyes University Nigde University

Element Added (mg) Found (mg) Recovery (%) Found (mg) Recovery (%)

Ni 0 5.8� 0.5 — N.D. —20.0 24.8� 0.2 95� 1 19.4� 0.6 97� 3

Cd 0 3.1� 0.1 — N.D. —20.0 23.6� 0.3 102� 2 20.3� 0.5 102� 2

Co 0 5.8� 0.6 — N.D. —

20.0 25.2� 0.9 97� 4 20.1� 0.7 100� 4

Cu 0 8.8� 0.5 — 4.2� 0.2 —20.0 28.6� 0.8 99� 4 24.5� 0.6 102� 3

Pb 0 13.8� 0.8 — 26.0� 2.2 —20.0 33.6� 0.7 99� 4 45.2� 0.9 96� 4

Cr 0 N.D. — N.D. —

20.0 20.2� 0.5 101� 2 20.3� 0.6 102� 3

N.D.: Not Detected.

Chelating Resin Preparation 653

higher than 95%, thus confirming the accuracy of the procedureand its independence from the matrix effects. These results confirm thevalidity of the proposed method.

Application to Natural Water Samples

The Amberlite XAD-16-PAN method has been employed for theseparation/preconcentration of Ni(II), Cd(II), Co(II), Cu(II), Pb(II)and Cr(III) in natural water samples. For that purpose, the proceduregiven in Experimental was applied. The results, which are shown inTable 4, have been calculated on the assumption of 100% recovery ofworking elements.

CONCLUSION

Based on these results found in the present study, it can be concludedthat XAD-16-PAN resin is an effective material for the separation andpreconcentration of traces metal ions in the natural water samples. Themethod gives a better preconcentration factor. The new resin can be usedat least 40 times. Future works will be focused on the usage of the resinon-line solid phase extraction of the metal ions and on the application of

Table 4. The concentration of analyte ions in the tap water samples from Nigde

city (n¼ 4).

Concentrationa (mg/L)

Sample Ni Cd Co Cu Pb Cr

Yenice Mahallesi 4.7� 0.3 BDL 1.1� 0.1 6.6� 0.3 7.6� 0.5 1.8� 0.1

Saruhan Mahallesi 3.5� 0.3 BDL 1.4� 0.2 7.2� 0.2 6.1� 0.2 1.7� 0.3Vali Cesmesi 3.0� 0.2 BDL 5.9� 0.1 5.9� 0.2 4.7� 0.3 BDLAmas Baglari 2.1� 0.2 BDL BDL 3.7� 0.4 2.8� 0.2 BDLSet Evler 2.9� 0.2 BDL 1.2� 0.1 4.3� 0.1 6.2� 0.3 1.8� 0.1

Selcuk Mahallesi 3.6� 0.3 BDL 0.9� 0.1 4.7� 0.2 5.8� 0.3 2.5� 0.3Terminal 3.1� 0.2 BDL 1.2� 0.1 5.4� 0.2 4.4� 0.3 2.4� 0.3Nigde Universitesi BDL BDL BDL 4.2� 0.2 26.0� 2.2 1.6� 0.6

Kampus (Yeni) 4.6� 0.2 0.6� 0.0 1.5� 0.2 5.1� 0.4 5.1� 0.4 2.6� 0.1

BDL: Below the detection limit.aUncertainty at 95% confidence limit.

654 Narin et al.

the method to other samples containing high salinity such as dialysissolution and urine etc.

ACKNOWLEDGMENT

Ibrahim Narin is grateful for the financial support of ResearchFoundation of Nigde University (Nigde-Turkey). The authors thankMr. E. Sahmetlioglu for his help on the IR evaluations.

REFERENCES

1. Minczevski, J.; Chwastowska, J.; Dybczynski, D. Separation andPreconcentration Methods in Inorganic Analysis; Ellis Horwood:Chichester, 1982.

2. Hansen, E.H.; Nielsen, S. Flow Injection and Atomic AbsorptionSpectrometry, An Effective and Attractive Analytical ChemicalCombination, Laboratory Robotics Automation 1998, 10, 347–354.

3. Soylak, M.; Elci, L.; Dogan, M. Solid phase extraction of tracemetal ions with amberlite XAD resins prior to atomic absorptionspectrometric analysis. J. Trace Microprobe Techn. 2001, 19,329–344.

4. Cai, Y.; Jiang, G.; Liu, J. Preconcentration of trace amounts ofcadmium in aqueous samples on mini columns packed with chromo-sorb series gas chromatographic stationary phases and its determina-tion by electrothermal atomic absorption spectrometry. Analyst2001, 126, 1678–1682.

5. Fang, Z.; Sperling, M.; Welz, B. Flame atomic absorptionspectrometric determination of lead in biological samples usinga flow injection system with on-line preconcentration bycoprecipitation without filtration. J. Anal. At. Spectrom. 1991, 6,301–306.

6. Yebra, M.C.; Garcıa, A.; Carro, N.; Moreno-Cid, A.; Puig, L.Design of a field flow preconcentration system for cadmium determi-nation in seawater by flow-injection-atomic absorption spectrometry.Talanta 2002, 56, 777–785.

7. Giokas, D.L.; Paleologos, E.K.; Prodromidis, M.I.; Karayannis, M.I.Development of 1-(2-pyridylazo)-2-naphthol-modified polymericmembranes for the effective batch pre-concentration and determina-tion of zinc traces with flame atomic absorption spectrometry.Talanta 2002, 56, 491–498.

Chelating Resin Preparation 655

8. Soylak, M. Determination of trace amounts of copper in metallicaluminium samples after separation and preconcentration on anactivated carbon column. Fresen. Environ. Bull. 1998, 7, 383–387.

9. Cesur, H.; Bati, B. Determination of cadmium by FAAS aftersolid-phase extraction of its 1-benzyl-piperazinedithiocarbamatecomplex on microcrystalline naphthalene. Turk J. Chem. 2002, 26,29–35.

10. Garg, B.S.; Sharma, R.K.; Bist, J.S.; Bhojak, N. Column chro-matographic preconcentration of cobalt and zinc with 3-hydroxy-4-imino-(n-20-pyridyl)-2-methylnaphthalen-1-one adsorbed onnaphthalene and their estimation in vitamin and milk samples.Indian J. Chem. 2002, 39A, 564 –566.

11. Quinaia, S.P.; da Silva, J.B.B.; Rollemberg, M.C.E.; Curtius, A.J.Preconcentration of lead complexed with O,O-diethyldithiopho-sphate by column solid-phase extraction using different sorbentsin a flow injection system coupled to a flame atomic absorptionspectrometer. Talanta 2001, 54, 687–696.

12. Bilba, D.; Bejan, D.; Tofan, L. Chelating sorbents in inorganicchemical analysis. Croat. Chem. Acta 1987, 71, 155–178.

13. Garg, B.S.; Sharma, R.K.; Bhojak, N.; Mittal, S. Chelating resinsand their applications in the analysis of trace metal ions, microchem.J. 1999, 61, 94–114.

14. Bogachiova, L.V.; Kovaliov, I.A.; Tsizin, G.I.; Formanovskii, A.A.;Zolotov, Y.A. On-line sorption preconcentration and atomicabsorption determination of palladium in solutions. Vestn. Mosk.Univ. Khim. 1999, 40, 110–114.

15. Dev, K.; Pathak, R.; Rao, G.N. Sorption behavior oflanthanum(III), neodymium(III), terbium(III), thorium(IV) anduranium(VI) on amberlite XAD-4 resin functionalized with bicineLligands. Talanta 1999, 48, 579–584.

16. Tewari, P.K.; Singh, A.K. Amberlite XAD-7 impregnated with xyle-nol orange: a chelating collector for preconcentration of Cd(II),Co(II), Cu(II), Ni(II), Zn(II) and Fe(III) ions prior to their deter-mination by flame AAS. Fresen. J. Anal. Chem. 2000, 367, 562–567.

17. Pathak, R.; Rao, G.N. Preparation and analytical properties of achelating resin functionalized with 1-hydrazinophthalazine ligand.Talanta 1997, 44, 1447–1453.

18. Pathak, R.; Rao, G.N. Synthesis and metal sorption studies ofP-tert-butylcalix[8]ayrene chemically bound to polymeric support.Anal. Chim. Acta 1996, 335, 283–290.

19. Saxena, R.; Singh, A.K.; Sambi, S.S. Synthesis of a chelating poly-mer matrix by immobilizing alizarin red-S on amberlite XAD-2 and

656 Narin et al.

its application to the preconcentration of lead(II), cadmium(II),zinc(II) and nickel(II). Anal. Chim. Acta 1994, 295, 199–204.

20. Saxena, R.; Singh, A.K. Pyrocatechol violet immobilizedamberlite XAD-2: synthesis and metal-ion uptake propertiessuitable for analytical applications. Anal. Chim. Acta 1997, 340,285–290.

21. Jain, V.K.; Sait, S.S.; Shrivastav, P.; Agrawal, Y.K. Application ofchelate forming resin amberlite XAD-2-o-vanillinthiosemicarbazoneto the separation and preconcentration of copper(II), zinc(II) andlead(II). Talanta 1997, 45, 397–404.

22. Kumar, M.; Rathore, D.P.S.; Singh, A.K. Amberlite XAD-2 func-tionalized with o-aminophenol: synthesis and applications as extrac-tant for copper(II), cobalt(II), cadmium(II), nickel(II), zinc(II) andlead(II). Talanta 2000, 51, 1187–1196.

23. Kumar, M.; Rathore, D.P.S.; Singh, A.K. Quinalizarin anchored onamberlite XAD-2. A new matrix for solid-phase extraction of metalions for flame atomic absorption spectrometric determination.Fresen. J. Anal. Chem. 2001, 370, 377–382.

24. Tewari, P.K.; Singh, A.K. Synthesis, characterization and applica-tions of pyrocatechol modified amberlite XAD-2 resin for precon-centration and determination of metal ions in water samples byflame atomic absorption spectrometry (FAAS). Talanta 2001, 53,823–833.

25. Soylak, M.; Elci, L. Preconcentration and separation of trace metalions from sea water samples by use of amberlite XAD-16 aftercomplexation with sodium diethyldithiocarbamate. Int. J. Envir.Anal. Chem. 1997, 66, 51–59.

26. Soylak, M.; Dogan, M. Separation and enrichment of zinc, iron,copper, cadmium, cobalt and nickel from urine with amberliteXAD-16 resin. Trace Elem. Electroly. 1996, 13, 130–132.

27. Soylak, M.; Elci, L.; Dogan, M. Determination of trace amounts ofcobalt in natural water samples as 4-(2-thiazolylazo) recorcinolcomplex after adsorptive preconcentration. Anal. Lett. 1997, 30,623–631.

28. Soylak, M.; Divrikli, U.; Dogan, M. Column separation and enrich-ment of trace amounts of Cu, Ni and Fe on XAD-16 resin in indus-trial fertilisers after complexation with 4-(2-thiazolylazo) resorcinol.J. Trace Microprobe Techn. 1997, 15, 197–204.

29. Soylak, M.; Divrikli, U.; Elci, L.; Dogan, M. Column chromato-graphic preconcentration of copper, nickel and iron in ammoniumsalts by graphite furnace atomic absorption spectrometry. Kuwait J.Science Eng. 1998, 25, 389–396.

Chelating Resin Preparation 657

30. Elci, L.; Soylak, M.; Uzun, A.; Buyukpatir, E.; Dogan, M.Determination of trace impurities in some nickel compounds byflame atomic absorption spectrometry after solid phase extractionusing amberlite XAD-16 resin. Fresen. J. Anal. Chem. 2000, 368,358–361.

31. Lee, C.H.; Suh, M.Y.; Kih, S.J.; Tae, Y.E.; Won, L. A chelatingresin containing 4-(2-thiazolylazo) resorcinol as the functionalgroup. Chromatographic application to the preconcentration andseparation of some trace metal ions including uranium. Anal.Chim. Acta 1997, 351, 57–63.

32. Lee, C.H.; Kim, J.S.; Suh, M.Y.; Lee, W. A chelating resin contain-ing 4-(2-thiazolylazo) resorcinol as the functional group synthesisand sorption behavior for trace metal ions. Anal. Chim. Acta 1997,339, 303–312.

33. Lee, C.H.; Suh, M.Y.; Kim, J.S.; Kim, D.Y.; Kim W.H., Eom, T.Y.Separation and preconcentration of uranium from geological mate-rials with chelating resin containing 4-(2-thiazolylazo) resorcinolfunctional groups, Anal. Chim. Acta 1999, 382, 199–203.

34. Lee, W.; Lee, S.E.; Lee, C.H.; Kim, Y.S.; Lee, Y.I. A chelating resincontaining 1-(2-thiazolylazo)-2-naphthol as the functional group;synthesis and sorption behavior for trace metal ions. Microchem.J. 2001, 70, 195–203.

35. Marczenko, Z. Separation and Spectrophotometric Determination ofElements; Wiley: Chichester, 1986.

36. Cheng, K.L.; Ueno, K.; Imamura, T. Handbook of OrganicAnalytical Reagents; CRC Press: Inc., Florida, 1982.

37. Soylak, M.; Dogan, M. Physical and chemical properties of themineral spring waters from central region of Anatolia, Turkiye.Fresen. Envir. Bull. 1995, 4, 35–40.

38. Narin, I.; Soylak, M.; Kayakirilmaz, K.; Elci, L.; Dogan, M.Speciation of Cr(III) and Cr(VI) in tannery wastewater andsediment samples on ambersorb 563 resin. Anal. Lett. 2002, 35,1437–1452.

Received August 20, 2002Accepted October 24, 2002

658 Narin et al.