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Öğe Concentration of cadmium, copper and zinc using water soluble polyacrylic acid polymer(Pergamon-Elsevier Science Ltd, 2000) Bakircioglu, Y; Seren, G; Akman, SIn this study, a simple method was developed to use water soluble polymer, polyacrylic acid, for the separation and pre-concentration of trace Cd, Cu and Zn prior to their analysis by flame atomic absorption spectrometry. For this purpose, the sample and poly-acrylic acid were mixed and the metal-bound polymer was precipitated by the addition of acetone. The precipitate was separated and dissolved in a minimum amount of water and aspirated into a flame AAS. The method was compared with traditional water insoluble sorbents in all aspects. The technique described is fast, simple, precise and inexpensive. Blank values were low and recoveries were 96.5% for Cd, 99.7% for Cu and 98.0% for Zn. Detection limits (3 sigma) were 1.8 mu g 1(-1) for Cd, 2.5 mu g 1(-1) for Cu, and 2.2 mu g 1(-1) for Zn. (C) 2000 Elsevier Science B.V. All rights reserved.Öğe Determination of cadmium, copper, and zinc by flame atomic absorption spectrometry after preconcentration using a DETA (diethylenetriamine) polymer(Marcel Dekker Inc, 2001) Bakircioglu, Y; Seren, G; Akman, SAn atomic absorption spectrometric method with a preconcentration and separation procedure using a DETA (diethlyenetriamine) polymer is proposed for the determination of Cd, Cu and Zn. The influence various experimental condition on retention and elution efficiencies of the analyte were investigated by applying batch and column techniques. All investigated elements were quantitatively retained at pH 3, then were completely recovered by means of nitric acid. The loading capacity of the DETA polymer is 5.2 mg Cu2+/g polymer. A contact time of one minutes is sufficient for quantitative retention and elution which is shorter than for many Other sorbents. In the presence of sodium chloride up to 0.5% the analyte elements were quantitatively Separated and recovered.Öğe Determination of some trace heavy metals in some water samples by FAAS after their preconcentration using DETA(Marcel Dekker Inc, 2003) Bakircioglu, Y; Akman, S; Biçak, N; Senkal, FDiethylenetriamine, DETA polymer was used as a preconcentration of cobalt, iron and nickel prior to their determination by flame atomic. ab-sorption spectrometry (FAAS). Both batch-and column methods were used for the separation and concentration of above metals. These metals were quantitatively retained on the proposed adsorbent at pH 21 then were quantitatively eluted with 2 M hydrochloric acid or nitric acid. The recoveries of metal ions were greater than 98%. Detection limits (3 delta) were 1.5 g/L for Co, 2 . I g/L for Fe and 1.9 g/L for Ni. The relative standard deviations for the determinations were found to be 1.0-8.8%. The effect of Na on the preconcentration of trace metals has also been investigated. The method was applied to tap, ground and lake water samples.Öğe Evaluation of Pb-Spec® for flow-injection solid-phase extraction preconcentration for the determination of trace lead in water and wine by flame atomic absorption spectrometry(Elsevier Science Bv, 2003) Bakircioglu, Y; Segade, SR; Yourd, ER; Tyson, JFTwo manifold designs were evaluated. Water samples and wine digests in 10% nitric acid were pumped through a column containing a commercially available resin (Pb-Spec(R)), an immobilized crown ether with a cavity size selective for Pb2+. The column was rinsed with 2% HNO3 and the eluent, 0.1 mol l(-1) ammonium oxalate was injected via a six-port rotary valve. The eluted lead was delivered to the flame atomic absorption spectrometer at 4.0 ml min(-1). The following flow-injection (FI) parameters were optimized: sample acidity and volume, loading and elution flow rates, and eluent composition and volume. The detection limit for the water samples, estimated from the noise on the signal obtained for 250 ml of 10 mug l(-1) loaded at 19.1 ml min(-1) was 1 mug l(-1). For 50 ml of wine digest loaded at 4 ml min(-1), the value was 3 mug l(-1). The roles of loading flow rate and sample volume were investigated in detail. The variation in retention efficiency with loading flow rate showed that the amount of lead retained (during a fixed loading time) increased with flow rate until the upper performance limit of the peristaltic pump was reached. The variation of detection limit with sample volume followed the expected hyperbolic relationship and showed that only small improvements in LOD were obtained for volumes greater than 50 ml. The method was evaluated through spike recovery for both water and wine. The lead contents of tap (0.24 mug l(-1)), pond (0.40 mug l(-1)), and river waters (not detected) were determined. The concentrations of lead in three Port wine samples ranged from not detected to 190 mug l(-1). No significant matrix suppression effects were observed. (C) 2003 Elsevier Science B.V. All rights reserved.Öğe Evaluation of syringe-connected minicolumn technique for preconcentration of some trace elements using chromosorb-103 and determination by flame atomic absorption spectrometry(Taylor & Francis Inc, 2004) Bakircioglu, Y; Bakircioglu, D; Akman, SA syringe-connected minicolumn (SCM) technique has been developed for preconcentration and enrichment of cobalt, iron, and lead in river-water samples prior to their determination by flame atomic absorption spectrometry (FAAS). The proposed technique is substituted for the classical batch and column techniques all of which are off-line methods. The method proposed was compared with the column technique with respect to easiness, rapidness, simplicity and some analytic performances such as recovery, precision, accuracy and risk of contamination. The minicolumn was filled with Chromosorb-103 as a sorbent. In order to retain the analyte elements, the sample solution was drawn into the syringe and discharged back passing through the sorbent in the minicolumn. The analyte elements were quantitatively retained at pH greater than or equal to4 if they were complexed with ammonium pyrrolidine dithiocarbamate (APDC) prior to passing through to the sorbent. The analytes sorbed on the minicolumn was then eluted with 1.0 mol L-1 HNO3 in acetone again drawing and discharging the eluent. Optimum flow rates of sample or eluent for sorption and elution procedure were 20 mL min(-1) for both drawing and discharging cases. The proposed technique was successfully applied to the determination of analytes in certified reference material and spiked river-water samples. The recoveries of analytes from certified reference material (Bovine liver) and river-water samples were quantitative and reproducible (>96%, with relative standard deviation (RSD) of 1-5%). The developed technique is simple, fast, and accurate. Detection limits (3sigma) were 4.8 mug L-1 for Co, 14 mug L-1 for Fe, and 15 mug L-1 for Pb. Very high preconcentration factors up to 200-fold could be achieved.Öğe Investigation on the preconcentration of trace elements on activated bentonite(Inst Lebensmitteltechnologie Analytische Chemie, 2001) Seren, G; Bakircioglu, Y; Çoban, F; Akman, SIn this study, activated bentonite was used for the separation and preconcentration of cobalt, copper and manganese prior to their determination by flame atomic absorption spectrometry (FAAS). The bentonite used in this study was obtained from west part of Turkey, Enez, Edirne. Optimum conditions for the separation and preconcentration of analyte elements were investigated. Bentonite was further purified by treating the material with 4.0 mol L-1 hydrochloric acid for the removal of contaminants before use. Both batch and column methods were used for the separation of the above metals. In the batch method, the effects of pH and shaking time on retention and elution were investigated. The elements were quantitatively retained by the collector at pH 4 and again quantitatively eluted with of 0.1 mol L-1 EDTA for Cc and Mri and 2.0 mol L-1 HCl for Cu and Mn. Blank values were low and recoveries were 99.2 +/- 2%, 99.6 +/- 1% and 99 +/- 1% for Co, Cu and Mn, respectively, at 95% confidence level. The relative standard deviations for the determinations were found to be 1.0-8.8%. Detection limits (3 sigma) were 1.5 mug L-1 for Co, 0.9 mug L-1 for Cu, and 1.4 mug L-1 for Mn. The maximum loading capacity was found to be 0.22 mg g(-1) bentonite for copper using batch procedure. The method was applied to the analysis of the elements studied in waste water and ground water.Öğe A novel preconcentration method for determination of iron and lead using Chromosorb-103 and flame atomic absorption spectrometry(Elsevier Science Bv, 2005) Bakircioglu, Y; Bakircioglu, D; Tokman, NSyringe connected-minicolumn (SCM) method for the preconcentration/separation of iron and lead prior to their determination by flame atomic absorption spectrometry (FAAS) was developed. The proposed method is substituted for classical batch and column methods. The method proposed was compared with the column method with respect to easiness, rapidness, simplicity and some analytical performance criteria such as recovery, precision, accuracy and risk of contamination. A minicolumn was filled with Chromosorb-103 as a sorbent and connected with a syringe. The experimental conditions such as pH of sample, concentration and amount of eluent, flow rates of sample and eluent, concentration of 8-hydroxyquinoline (oxine) as a complexing agent were optimized. The sample solution with or without oxine was drawn into the syringe and discharged manually passing through the resin. Analytes were retained at pH >= 5 and eluted with I M nitric acid in acetone quantitatively. Analyte elements could be concentrated up to 200-fold. The iron and lead in river-water samples and in certified reference Bovine Liver (NIST 1577b) were quantitatively recovered with relative standard deviation lower than 10%. (c) 2005 Elsevier B.V. All rights reserved.Öğe Preconcentration of nickel and cobalt prior to their determination by graphite furnace atomic absorption spectrometry using the water-soluble polymer poly(vinyl pyrrolidinone)(Springer Wien, 2004) Tokman, N; Akman, S; Bakircioglu, YThe use of a water-soluble polymer, poly(vinyl pyrrolidinone) (PVP), for the preconcentration and separation of nickel and cobalt prior to their determination by graphite furnace atomic absorption spectrometry is described. For this purpose, the sample and the water-soluble polymer solutions were mixed, and the metal-bound polymer was precipitated by pouring the mixture into acetone. The precipitate was separated by decantation and dissolved with distilled-deionized water. The analyte elements were determined by graphite furnace atomic absorption spectrometry. The validity of the method was tested with spiked sea water and mineral water samples. The analytes added to the samples were quantitatively recovered within the range of 95% confidence limits. The proposed technique is fast, simple, precise and inexpensive. Its low blank values and high precision are other important advantages.Öğe Solid phase extraction of bismuth and chromium by rice husk(Marcel Dekker Inc, 2003) Bakircioglu, Y; Bakircioglu, D; Akman, SA major agricultural waste, rice husk and its ash were used for the preconcentration and separation of bismuth and chromium prior to their determination by flame atomic absorption spectrometry (FAAS) and their sorption properties with respect to bismuth and chromium from water samples were investigated. For this purpose, rice husk was thermally treated at 300degreesC for one hour and 600degreesC for ten hours in a muffle furnace. The effects of various experimental conditions on retention and elution efficiencies of studied elements for untreated rice with husk, untreated and thermally treated rice husk were investigated by applying batch and column methods. The analyte elements were quantitatively collected on rice with husk, the untreated and thermally treated rice husk at 300degreesC if the pH is above 3. The analvte elements retained on the rice with husk, rice husk or its ash were completely recovered by means of 2.0 M hydrochloric acid. Maximum chromium adsorption capacities of untreated rice with husk (URH), rice husk (RH), rice husk ash heated at 300degreesC (RHA-300) and 600degreesC (RHA-600) are 0.12, 0.50, 19.09 and 6.49 mg Cr/g adsorbent, respectively and 0.47, 294, 18.34 and 4.90 mgBi/g adsorbent, respectively. When RHA-300 was used which is the most suitable adsorbent of all, detection limits (3 delta) were 13 mug/L for Bi and 1.5 mug/L for Cr. The relative standard deviations for the determinations were found to be 1.0-7.9%. The results showed that RHA especially heated at 300degreesC could be used as an efficient and cheap adsorbent for the removal of some heavy metals from the natural water samples and for the preconcentration and separation of bismuth and chromium prior to their determination by flame atomic absorption spectrometry.Öğe Use of a packed minicolumn connected to a syringe for determination of trace elements in biological and water samples by flame atomic absorption spectrometry(Springer Wien, 2004) Bakircioglu, Y; Bakircioglu, D; Akman, SIn this study, a syringe-connected minicolumn resin was used for the separation and enrichment of cadmium, copper, nickel and zinc prior to their determination by flame atomic absorption spectrometry. The proposed technique was compared with classical batch and column techniques in terms of rapidness, simplicity, enrichment and risk of contamination. The minicolumn was filled with Chromosorb-103 resin and connected to a syringe. If the samples were treated with ammonium pyrrolidine dithiocarbamate or 8-hydroxyquinoline, the analytes were quantitatively retained at pH greater than or equal to 2 and pH greater than or equal to 5 on the resin, respectively. On the other hand, if no chelating agent was added, the analytes were quantitatively retained at pH greater than or equal to 10. The analytes retained by the resin were quantitatively eluted by drawing and discharging nitric acid in acetone. The analytes in spiked river-water samples and in certified standard reference Bovine-Liver (NIST SRM 1577 b) were quantitatively (greater than or equal to94%) recovered. The relative standard deviations for the determinations were found to be 1.0-10%.
