Özcan Yalçınkaya

Synthesis of nano B2O3/TiO2 composite material as a new solid phase extractor and its application to preconcentration and separation of cadmium

A new solid phase extractor, nano-scale diboron trioxide/titanium dioxide composite material, was synthesized and used for separation and/or preconcentration of trace cadmium ion from various samples. The characterization of the synthesized material was performed by scanning electron microscope (SEM), transmission electron microscope (TEM) and X-ray diffractometer methods (XRD). The specific surface area of the material was also determined and found as 3.4m(2)/g. Analytical parameters including pH of sample solution, sample volume, flow rate of sample solution, volume and concentration of eluent for the column solid phase extraction (SPE) procedure were examined. The effect of common matrix ions on the recovery of the cadmium has also been investigated and found that they did not interfere on cadmium preconcentration. Under the optimum experimental conditions, preconcentration factor and analytical detection limit were determined as 50 and 1.44 microg/L, respectively. The reusability (stabile up to 100 run) and adsorption capacity (49 mg/g) of the sorbent were excellent. The accuracy of the method was confirmed by analyzing certified reference materials (Tea leaves GBW-07605). The results demonstrated good agreement with the certified values (relative error <10%). The precision of the method was also satisfactory. The recovery of cadmium under the optimum conditions was found to be 96+/-3% at 95% confidence level. The method was applied for the determination of cadmium in tap water and tea leaves.

Chelating agent free-solid phase extraction (CAF-SPE) of Co(II), Cu(II) and Cd(II) by new nano hybrid material (ZrO2/B2O3)

New nano hybrid material (ZrO(2)/B(2)O(3)) was synthesized and applied as a sorbent for the separation and/or preconcentration of Co(II), Cu(II) and Cd(II) in water and tea leaves prior to their determination by flame atomic absorption spectrometry. Synthesized nano material was characterized by scanning electron microscope, transmission electron microscope and X-ray diffraction. The optimum conditions for the quantitative recovery of the analytes, including pH, eluent type and volume, flow rate of sample solution were examined. The effect of interfering ions was also investigated. Under the optimum conditions, adsorption isotherms and adsorption capacities have been examined. The recoveries of Co(II), Cu(II) and Cd(II) were 96 ± 3%, 95 ± 3%, 98 ± 4% at 95% confidence level, respectively. The analytical detection limits for Co(II), Cu(II), and Cd(II) were 3.8, 3.3, and 3.1 μg L(-1), respectively. The reusability and adsorption capacities (32.2 mg g(-1) for Co, 46.5 mg g(-1) for Cu and 109.9 mg g(-1) for Cd) of the sorbent were found as satisfactory. The accuracy of the method was confirmed by analyzing certified reference material (GBW-07605 Tea leaves) and spiked real samples. The method was applied for the determination of analytes in tap water and tea leaves.

Separation and preconcentration of trace manganese from various samples with Amberlyst 36 column and determination by flame atomic absorption spectrometry

This work assesses the potential of a new adsorptive material, Amberlyst 36, for the separation and preconcentration of trace manganese(II) from various media. It is based on the sorption of manganese(II) ions onto a column filled with Amberlyst 36 cation exchange resin, followed by the elution with 5mL of 3mol/L nitric acid and determination by flame atomic absorption spectrometry (FAAS) without interference of the matrix. Different factors including pH of sample solution, sample volume, amount of resin, flow rate of sample solution, volume and concentration of eluent, and matrix effects for preconcentration were investigated. Good relative standard deviation (3%) and high recovery (>95%) at 100mug/L and high enrichment factor (200) and low analytical detection limit (0.245mug/L) were obtained. The adsorption equilibrium was described well by the Langmuir isotherm model with maximum adsorption capacity of 88mg/g of manganese on the resin. The method was applied for the manganese determination by FAAS in tap water, commercial natural drinking water, commercial treated drinking water and commercial tea bag sample. The accuracy of the method is confirmed by analyzing the certified reference material (tea leaves GBW 07605). The results demonstrated good agreement with the certified values.

Preconcentration, Speciation, and Determination of Mercury by Solid Phase Extraction with Cold Vapor Atomic Absorption Spectrometry

In this study, inorganic mercury [iHg (Hg2+)] and monomethylmercury [MeHg (CH3Hg+)] ions have been preconcentrated and determined by a column solid phase extraction method. Cold vapor atomic absorption spectrometry was used for the determination of mercury species. Optimum retention and elution parameters were determined for both mercury species separately. For this purpose, the effect of pH, flow rate and volume of sample solution, type, and concentration of eluent on the recovery of mercury species were investigated. Effects of possible interfering ions were also studied. Optimum values of flow rate, pH, and volume of sample solution were found to be 3 mL min−1, 4.0 and 50 mL, respectively, for both iHg and MeHg ions. Although the both species were retained at pH 4, the elution could be performed only with different eluents. While MeHg ions were eluted with 10 mL of 0.1 mol/L HCl solution, iHg ions were eluted with 10 mL of 0.2 mol L−1 thioureasolution in 3 mol L−1HCl. Limits of detection for iHg and MeHg were 0.44 µg L−1 and 0.56 µg L−1, respectively. To validate the proposed speciation and/or preconcentration method, a certified reference material (ERM-CE464) was analyzed and MeHg was determined with a relative error of 7.3%. The accuracy was also checked by analyzing spiked water and fish samples for both species.

Preconcentration of Aluminum on Nano ZrO2/B2O3 and Its Determination by Flame Atomic Absorption Spectrometry

ABSTRACT This study presents a chelating agent free solid phase extraction method for preconcentration of Al(III) using hybrid nano zirconium dioxide–boron oxide (ZrO2/B2O3) sorbent. This method is based on the sorption of Al(III) ions directly onto nano sorbent, followed by the elution with 10 mL of 4 mol L−1 HNO3 and determination by flame atomic absorption spectrometry (FAAS). Preconcentration parameters, including pH of the sample solution, volume and concentration of the eluent, sample volume, and flow rate of the sample solution, that affect the recovery of the Al(III) ions have been optimized. Under the optimized experimental conditions, analytical parameters such as limit of detection, limit of quantification, linear working range, precision, and accuracy were determined. The analytical limit of detection for Al(III) was found as 7.71 µg L−1. The reusability and adsorption capacity of the new hybrid sorbent for Al(III) ions were also investigated. Interfering effects of matrix constituent on the recovery of the Al(III) ions were studied. The accuracy of the method was checked by determining Al(III) ions in a certified reference water sample (SPS-WW1 Waste Water). The proposed procedure was applied for the determination of Al(III) ions in dam waters.

High-resolution continuum source flame atomic absorption spectrometric (HR-CS FAAS) determination of trace aluminium and lead in water and some beverage samples after separation and preconcentration procedure

In the present study, a solid phase extraction procedure has been presented for the separation and preconcentration of aluminium (Al) and lead (Pb) in various matrixes such as water, cola and fruit juice samples. 4-[(3-amino-5-{[(2-hydroxyphenyl) methylidene] amino}-1H-pyrazol-4-yl) diazenyl] benzoic acid (AHPMAPDAB) was used as a ligand. AHPMAPDAB chelates of Al and Pb ions in aqueous solutions were adsorbed on polystyrene-graft-ethyl methacrylate copolymer (Poly S15-g-EMA120). Various experimental and analytical parameters such as sample solution pH, sample volume, flow rate of sample solution and eluent, volume and concentration of eluent, amount of ligand and adsorbent, effect of common matrix ions and capacity of adsorbent were investigated. The adsorbed metal ions on resin were eluted with 6 mL of 2 mol L−1 HCl solutions and their concentrations were determined by high-resolution continuum source flame atomic absorption spectrometry (HR-CS FAAS). Under the optimised conditions, limits of detections were 0.32 μg L−1 and 0.24 μg L−1 for Al and Pb, respectively. The accuracy of the procedure was confirmed by analysing certified materials (NIST SRM 1643e, Trace elements in water) and spiked real samples. The developed procedure was successfully applied to real samples.

Synthesis and characterization of nano-scale alumina on single walled carbon nanotube

In this study, nano-scale crystalline alumina was synthesized on single walled carbon nanotube by sol-gel method for using as a sorbent for solid phase extraction of trace metals. The characterization of the synthesized nanocomposite material was performed by scanning electron microscope, transmission electron microscope and X-ray diffractometer methods. It was proved that the obtained composite material was mainly nano-scale Al2O3, and partly Mg2Al2O4 and Zn2Al2O4 on single walled carbon nanotube. In addition, the specific surface area of the material was determined and found as 165 m2/g. The adsorption capacity of the nanomaterial was also determined for cadmium(II) ions and found as 2.18 mg/g at pH 8.

Assessment of arsenic, chromium, copper and manganese determination in thermal spring waters by electrothermal atomic absorption spectrometry using various chemical modifiers

Determination of total arsenic, chromium, copper and manganese in hot spring waters containing highly complex matrices and interferences by electrothermal atomic absorption spectrometry (ETAAS) was carried out in the presence of Ni, Pd, Ni + Pd and Ni + Pd + citric acid (CA) as chemical modifiers. Pyrolysis and atomization temperatures of analytes in sample and aqueous standard solutions, atomization and background profiles of analytes in sample solutions were obtained with and without modifiers and compared with each other. Effects of mass and mass ratio of modifiers were also studied. Limit of detection (LOD), limit of quantification (LOQ) and characteristic masses (mo) of analytes were found in the presence and absence of modifiers. Among the tested modifier mixtures, the Ni + Pd + CA modifier mixture was found to be preferable for the determination of analytes. The lowest LOD and mo values obtained with Ni + Pd + CA were 0.8 μg L−1 and 32 pg for As, 0.5 μg L−1 and 5.0 pg for Cr, 0.6 μg L−1 and 18 pg for Cu and 0.4 μg L−1 and 4 pg for Mn, respectively. The percent relative error found was below 5% for the determination of the analytes by the proposed method in the certified reference materials (CRMs) of water (Spsww-1 and 1643e). Arsenic in CRMs and sample solutions was also determined by hydride generation atomic absorption spectrometry (HGAAS) for the purpose of comparing with As results obtained by ETAAS. Results of analytes in sample solutions were compared with national and international water quality guidelines such as WHO and US EPA values, as well as literature data.

Preconcentration and Determination of Manganese and Nickel from Various Water Samples by Nano Zirconium Oxide/Boron Oxide

ABSTRACT This work assesses the potential of the adsorptive material nano zirconium oxide/boron oxide (ZrO2/B2O3) for removal of trace Mn(II) and Ni(II) from environmental samples. This method is based on the sorption of Mn(II) and Ni(II) ions directly onto nanosorbent, followed by the elution and determination by flame atomic absorption spectrometry (FAAS). Experimental parameters, including pH of sample solution, volume and concentration of eluent, sample volume, and flow rate of sample solution, that affect the recovery of the Mn(II) and Ni(II) ions from model solutions have been optimized. Under the optimum conditions, adsorption isotherms and adsorption capacities have been examined. The recoveries of Mn(II) and Ni(II) were 96% ± 2% and 95% ± 3% at 95% confidence level, respectively. The analytical detection limits for Mn(II) and Ni(II) were 1.9 and 4.9 µ g L−1, respectively. Adsorption capacities of the nano ZrO2/B2O3 were found as 92.8 mg g−1 for Mn and 168.4 mg g−1 for Ni. The accuracy of the method was checked by analyzing certified reference material (SPS-WW1 wastewater) and spiked real samples. The method was applied for the determination of analytes in water samples.

Evaluation of Activation Energies for Cadmium Atomization on Different Atomizer Surfaces and Modifier Solutions in Electrothermal Atomic Absorption Spectrometry

ABSTRACT Cadmium atomization on W, Ru, and W + Ru modifier–coated platforms and pyrolytic graphite–coated platforms with and without W, Ru, W + Ru, and Pd + Mg modifier solutions was obtained by electrothermal atomic absorption spectrometry (ETAAS). Surface morphologies of coated and uncoated platforms were investigated by scanning electron microscopy to show the evidence of coating. Pyrolysis, peak appearance, and atomization temperatures of Cd with or without coated platforms and modifier solutions were obtained. The activation energies and frequency factors of Cd atomization were found and evaluated. Results obtained were comprehensively compared with each other and published values.