共查询到20条相似文献,搜索用时 15 毫秒
1.
Şerife Saçmacı Serkan Şahan Mustafa Saçmacı Uğur Şahin Ahmet Ülgen Şenol Kartal 《International journal of environmental analytical chemistry》2013,93(12):1223-1235
A method was developed for the on-line determination of palladium in complex matrices with flame atomic absorption spectrometry (FAAS) using Amberlite XAD-16 resin functionalized with 2-[2-(5-thiol-1,3,4-thiadiazolyl)]-azonaphthol (TTAN) reagent. Optimum experimental conditions such as pH of sample, type of eluent, amount of resin, volumes of sample and eluent solution, flow rates of sample and eluent, and effect of interfering ions were established. A 0.1?mol?L?1 thiourea solution in 0.5?mol?L?1 HCl was used as the eluent and subsequently transportation the analyte ions into the nebulizer–burner system for atomization. The synthesized chelating resin material showed excellent chemical and mechanical resistance, fast adsorption kinetics permitting the use of high sample flow rates without significant losses of retention efficiency. The detection limit of the method was 1.5?µg?L?1 while the relative standard deviation (RSD%) was 2.4% at 0.1?mg?L?1 Pd(II) level. The developed method was successfully applied to the determination of palladium in the catalytic converter and water samples. 相似文献
2.
3.
A preconcentration method is developed for the on-line determination of palladium in complex matrices with flame atomic absorption spectrometry (FAAS). The flow system comprised of a minicolumn filled with polyamine Metalfix-Chelamine resin which is highly selective for Pt(IV), Au(III) and Pd(II). Best preconcentration conditions are established by testing different resin quantities, sample and eluent solution volumes, and adsorption and elution steps flow rates. Sample volumes of 4.7 ml of palladium solutions resulted in an enrichment factor of twenty at the optimum hydrodynamic conditions. This value can be increased by injecting larger volumes of sample solution. The method is sensitive, easy to operate and permitted the determination of sub-mg l−1 levels of palladium with a detection limit of 0.009 mg l−1. The resin was used up to 60 times in consecutive retention-elution cycles without any appreciable deterioration in its performance. The applicability of this method was tested by determining the palladium content in synthetic geological samples as well as in the pellet-type used car catalyst reference material. 相似文献
4.
González García MM Sánchez Rojas F Bosch Ojeda C García de Torres A Cano Pavón JM 《Analytical and bioanalytical chemistry》2003,375(8):1229-1233
A method to determine trace amounts of platinum in different samples based on electrothermal atomic absorption spectrometry is described. The preconcentration step is performed on a chelating resin microcolumn [1,5-bis(2-pyridyl)-3-sulfophenyl methylene thiocarbonohydrazide (PSTH) immobilized on an anion-exchange resin (Dowex 1x8-200)] placed in the autosampler arm. The combination of a peristaltic pump for sample loading and the atomic absorption spectrometer pumps for elution through a selection valve simplifies the hardware. The peristaltic pump and the selection valve are easily controlled electronically with two switches placed in the autosampler, which are activated when the autosampler arm is down. Thus, the process is fully automated without any modification of the software of the atomic absorption spectrometer. Under the optimum conditions with a 60-s preconcentration time, a sample flow rate of 2.4 mL min(-1), and an injection volume of eluent of 40 microL, a linear calibration graph was obtained in the range 0-100 ng mL(-1). The enrichment factor was 14. The detection limit under these conditions is 1 ng mL(-1), and the relative standard deviation (RSD) is 1.6% for 10 ng mL(-1) of Pt. The method has been applied to the determination of platinum in catalyst, vegetation, soil, and natural water samples. The results showed good agreement with the certified value and the recoveries of Pt added to samples were 98-105%. 相似文献
5.
Catalina Bosch Ojeda Fuensanta Sánchez Rojas José Manuel Cano Pavón 《Mikrochimica acta》2007,158(1-2):103-110
Palladium(II) is preconcentrated on a chelating resin microcolumn [1,5-Bis(2-pyridyl)-3-sulphophenyl methylene thiocarbonohydrazide
immobilized on an anion-exchange resin (Dowex 1 X8-200)] placed in the autosampler arm, followed by the elution of the Pd-chelate
with nitric acid and subsequent determination of Pd from the eluate by graphite furnace atomic absorption spectrometry. The
method was applied to the recovery of Pd(II) ions from different samples. 相似文献
6.
The flow-injecton preconcentration of lead with immobilised reagents under a variety of conditions is discussed. Timed sample loading and matrix removal without passing the matrix to the nebuliser were achieved simply with one valve. Reagent consumption and calibration time were reduced by the addition of further valves. A system design incorporating control of the timing of operations by a commercial autosample is described. The effects of pH and interferent ions were examined. Water samples were analysed against aqueous standards and as standard additions solutions. For an analysis time of about 3 min a preconcentration factor of about 40 was obtained for both peak height and area measurements. Detection limits of down to 1.4 ml?1 were obtained. 相似文献
7.
Ricardo J Cassella Otto I B Magalh?es Marcos Tadeu Couto Edson Luiz S Lima Marcia Angélica F S Neves Fernanda Margarida B Coutinho 《Analytical sciences》2005,21(8):939-944
In this work, flame atomic absorption spectrometry (FAAS) was used as a detector for the determination of zinc in natural water samples with a flow-injection system coupled to solid-phase extraction (SPE). In order to promote the on-line preconcentration of zinc from samples a minicolumn packed with 35 mg of a styrene-divinylbenzene resin functionalized with (S)-2-[hydroxy-bis(4-vinylphenyl)methyl]pyrrolidine-1-carboxylic acid ethyl esther was utilized. The system operation was based on Zn(II) ion retention at pH 9.5 +/- 0.5 in such a minicolumn with analyte elution, at the back flush mode, with 1 mol L(-1) HCl directly to the FAAS nebulizer. The influence of the chemical (sample pH, buffer concentration, HCl eluent concentration and effect of the ionic strength) and flow (sample and eluent flow rates and preconcentration time) parameters that could affect the performance of the system were investigated as well as the possible interferents. At the optimum conditions, for 2 min of preconcentration time (9.9 ml of sample volume), the developed methodology presented a detection limit of 1.1 microg L(-1), a RSD of 3.5% at 10 microg L(-1) and an analytical throughput of 24 h(-1). Whereas, for 4 min of the preconcentration time (19.8 ml of sample volume) a detection limit of 0.98 microg L(-1), a RSD of 6.5% at 5 microg L(-1) and a sampling frequency of 13 h(-1) are reported. 相似文献
8.
交联壳聚糖分离富集-火焰原子吸收法测定水样中痕量银 总被引:3,自引:0,他引:3
以甲醛、环硫氯丙烷为交联剂,由壳聚糖合成了一种新型的交联壳聚糖微球(FCCIS)分离树脂,研究了不同条件下FCCTS对Ag(Ⅰ)的吸附性能.在pH 3.6时FCCTS对Ag(Ⅰ)定量吸附,吸附在树脂上的Ag(Ⅰ)可用0.5 moL/L的氨水将其洗脱,用火焰原子吸收光谱测定.该法对Ag(Ⅰ)的检出限为61 ng/mL(3σ,n=8),相对标准偏差为2.2%(n=7,ρ=2μg/mL),线性范围为0.05~4μg/mL,加标回收率在98.8%~101.7%之间.该法已用于水样中痕量银测定. 相似文献
9.
The versatility of flow injection as a procedure for enhancing the performance of atomic spectrometry is demonstrated by the on-line separation and preconcentration of analyte ions of interest for methods employing atomic spectrometric measurements. In this paper, a sensitive method for the determination of palladium by flame atomic absorption spectrometry associated on-line with the flow injection technique has been developed. A flow system comprising a micro-column packed with activated carbon fibre was used for the concentration of palladium. In order to further enhance the performance of the analysis a new manifold with an additional column has been designed to increase the sensitivity by doubling the analytical signals. The method is sensitive and easily operating with a sampling rate of 15-20/h. The detection limit of this method is 0.3 ng/ml in standard solution and the precision is 3.9% relative standard deviation at 50 ng/ml. Recoveries of palladium in spiked solutions are 103-107%. 相似文献
10.
Flow analysis preconcentration of Mg and Zn using emulsions for flame atomic absorption spectrometry
T. Yokoyama Takashi Watarai Takeo Uehara Koh-ichi Mizuoka Kenji Kohara Masato Kido Michio Zenki 《Analytical and bioanalytical chemistry》1997,357(7):860-863
A preconcentration method combining Water/ Oil/Water (W/O/W) emulsions with flow injection manifolds has been developed for
determinations of Mg and Zn. The system consists of a mixing coil filled with Span 80 as a surfactant, palmitic acid or di(2-ethylhexyl)
phosphate as an extractant, kerosene as a solvent in the oil phase, and HCl in the inner aqueous phase to form W/O emulsions,
an extraction coil for the sample solution to form W/O/W emulsions, a phase separator to waste the outer aqueous phase, a
dry bath to demulsify W/O emulsions with 2-ethylhexanol, a phase separator to waste the oil phase, and an air pump to deliver
the concentrated sample solution to the flame atomic absorption spectrophotometer. This method proved to be excellent regarding
the reproducibility, the rapidity, and the small quantity of sample, compared with the W/O/W emulsions method without the
flow injection manifolds. The signal of flame atomic absorption spectrometry (FAAS) after preconcentration of Mg by this method
was 2.4 times as large as that before preconcentration. Also, this method suppressed some interferences. The system was applied
to FAAS determinations of Mg and Zn in duralumin alloys and Zn in commercial reagents.
Received: 20 March 1996/Revised: 13 July 1996/Accepted: 20 July 1996 相似文献
11.
A method using bi-directional electrostacking (BDES) in a flow system is presented for As preconcentration and speciation analysis. Some parameters such as electrostacking time and applied voltage, support buffers and their concentrations were investigated. Boric acid plus sodium hydroxide at 0.1 mol/l concentration was selected as support buffer to improve the pre-concentration factor (PF) for As(V). An analytical range from 2.0 to 50.0 μg l−1, and 0.35 μg l−1 as limit of detection, when applied 750 V for 20 min, were achieved. Under these conditions, a pre-concentration factor of 4.8 was obtained. The proposed method was applied to determine As(V) in mineral water and natural water samples (river, fountain and gold mine) from Ouro Preto city. Recoveries from 93.5 to 106.4% were achieved at 10 μg l−1 added As level (R.S.D.s between 3 and 7%). Potassium permanganate (10 mg l−1) was used for oxidising As species in order to determine total As, being established the concentration of As(III) from the difference between total As and As(V). 相似文献
12.
Preconcentration was effected using a 50 mm × 2 mm i.d. minicolumn packed with a spherical cellulose sorbent with chemically bound quinolin-8-ol function groups (Ostorb Oxin). The column was connected to the nebulizer of the atomic absorption spectrometer and the sample solution and eluent (2 M hydrochloric acid) were sucked through it at a flow-rate of 2–3 ml min?1 by utilizing the negative pressure of the nebulizer. The experimental design was tested with the determination of traces of copper. Peak-area and peak-height measurements were compared. Owing to the simple calibration, the former method was used for quantification. The dynamic range was from 0.3 ng ml?1 (detection limit) to 5 μg ml?1 (breakthrough). The reproducibility in the concentration range 25 ng ml?1-5 μg ml?1 was better than 5%. Water-soluble inorganic salts, ammonia and sodium hydroxide were analysed. The accuracy of the results was checked by anodic-stripping voltammetry and by electrothermal AAS. 相似文献
13.
Zheng Wang Dong-Mei Fang Qing Li Ling-Xia Zhang Rong Qian Yan Zhu Hai-Yun Qu Yi-Ping Du 《Analytica chimica acta》2012
A modified SBA-15 mesoporous silica material NH2-SBA-15 was synthesized successfully by grafting γ-aminopropyl-triethoxysilane. The material was characterized using transmission electron microscopy (TEM) and Fourier transform infrared/Raman (FT-IR/Raman) spectroscopy, and used for the first time in a flow injection on-line solid phase extraction (SPE) coupled with flame atomic absorption spectrometry (FAAS) to detect trace Cr (VI). Effective sorption of Cr (VI) was achieved at pH 2.0 with no interference from Cr (III) and other ions and 0.5 mol L−1 NH3·H2O solution was found optimal for the complete elution of Cr (VI). An enrichment factor of 44 and was achieved under optimized experimental conditions at a sample loading of 2.0 mL min−1 sample loading (300 s) and an elution flow rate of 2.0 mL min−1 (24 s). The precision of the 11 replicate Cr (VI) measurements was 2.1% at the 100 μg L−1 level with a detection limit of 0.2 μg L−1 (3 s, n = 10) using the FAAS. The developed method was successfully applied to trace chromium determination in waste water. The accuracy was validated using a certified reference material of riverine water (GBW08607). 相似文献
14.
A method for the quantitative preconcentration of lead based on an existing batch process was developed for implementation in a flow system including a flame AAS detector. Lead can be quantitatively preconcentrated as pyrrolidinedithiocarbamate or dithizonate on an activated carbon minicolumn. The chelates are eluted in methyl isobutyl ketone and introduced directly into the nebuliser-burner. An enrichment factor of 50 is typically obtained for a preconcentration time of 2 min (lead can be determined at concentrations between 15 and 400 ng/ml), which results in a throughput of ca. 25 samples per hr. The sensitivity achieved with the two reagents is similar, but the selectivity provided by APDC exceeds that of dithizone. Based on the results obtained in the determination of lead in reference materials (minerals and skim milk), the proposed APDC method is applicable to real samples. 相似文献
15.
The conditions for determining platinum by electrothermal atomic absorption spectrometry after its extraction-chromatographic preconcentration and separation from iron(III) and copper(II) were selected. A procedure was developed that allows 0.01–0.1 mg/L platinum to be determined with a relative standard deviation of 5–7 % in the presence of 1000-fold amounts of Fe(III) and Cu(II).Translated from Zhurnal Analiticheskoi Khimii, Vol. 60, No. 1, 2005, pp. 41–44.Original Russian Text Copyright © 2005 by Moskvin, Yakimova, Alekseeva. 相似文献
16.
A. Rehber Türker Hüseyin Bağ Baki Erdoğan 《Analytical and bioanalytical chemistry》1997,357(3):351-353
By using a new adsorbent (sepiolite) an adsorption-elution and atomic absorption spectrometric method has been developed
for the preconcentration and determination of Fe and Pb. Recoveries of the analytes were 82 ± 3% for Fe and 91 ± 2% for Pb
at 95% confidence level. For Cu it was only 5 ± 1%. The recovery of iron could be increased to about 97 ± 1% by complexing
with EDTA, the recovery of copper only to 57 ± 2%. The optimised method was applied to the determination of lead in metal
materials (e.g. brass).
Received: 20 February 1996 / Revised: 7 May 1996 / Accepted: 11 May 1996 相似文献
17.
18.
19.
Burguera M Burguera JL Rivas D Rondón C Carrero P Alarcón OM Peña YP Brunetto MR Gallignani M Márquez OP Márquez J 《Talanta》2005,68(2):219-225
A sensitive and selective method was developed for the determination of traces of manganese in urine using on-line electrochemical preconcentration followed by flame atomic absorption spectrometry detection. A home made flow-through polypropylene cell (4.5 cm long × 0.8 cm diameter filled with glass marbles) with an effective inner volume of 0.5 ml containing a working and a counter electrode, both of glassy carbon and a Pt pseudo reference electrode was located in a flow injection manifold specially designed for the purpose of this work. The manganese was deposited from buffer solution of NH3/NH4Cl at pH 9.00 through an oxidizing process at a current of 400 mA during 7 min. A flow of HCl 0.1 mol l−1 at 4 ml min−1 through the cell, chemically dissolved the deposit. A small portion (15 μl) of the concentrate was introduced in a continuously flowing system by means of a timing device and was then carried to the detector for the manganese quantification. All electrochemical and spectroscopic variables as well as possible interferences in both systems were systematically studied. The relative standard deviations for ten consecutive measurements of manganese solutions of 2.0 and 20 μg l−1 were of 2.3 and 1.5%, respectively, while for a sample processed five times was less then 5%. The accuracy of the developed procedure was evaluated by adding known amounts of manganese standard to urine samples and following the whole procedure. Recoveries within the range 97.2-102.8% were obtained. To further prove the accuracy, a Seronorm Trace Elements in Urine, Batch 403125 sample with a reported concentration of 13 μg Mn l−1 was also analyzed. The experimental value obtained was of 12.7 ± 0.1 μg l−1, which does not differ significantly from the reported amount (p < 0.05). A preconcentration factor of 40, a linear range between 0.015 and 60 μg l−1 and a limit of detection of 15 ng l−1 permitted the determination of manganese in real urine samples from non-exposed subjects in the range 0.5-2.8 μg l−1. 相似文献
20.
Shaoming ZhangQiaosheng Pu Peng LiuQiaoyu Sun Zhixing Su 《Analytica chimica acta》2002,452(2):223-230
A simple and highly selective flow injection (FI) on-line preconcentration and separation flame atomic absorption spectrometric (FAAS) method was developed for the determinations of trace amounts of silver, gold and palladium. The selective preconcentration of the noble metals was achieved in a wide range of sample acidity (0.1-6 M HNO3 or HCl) on a microcolumn packed with amidinothioureido-silica gel (ATuSG). The analytes retained on the column were effectively eluted with 5.0% thiourea solution. The analytical procedure was optimized for sample acidity, elution, interferences, flow rate of sampling and eluting, and concentration of sample. Common co-existing cations and anions did not interfere with the preconcentration and determination of the three metals. At a sample loading flow rate of 4.5 ml min−1 with 60 s preconcentration, detection limits (3σ) of 1.1 ng ml−1 Ag, 13 ng ml−1 Au and 17 ng ml−1 Pd were obtained. The precisions (R.S.D., n=11) were 1.2% for Ag, 1.2% for Au and 1.7% for Pd, respectively. The detection limits can be further improved by increasing sample volume. The analytical results obtained by the proposed method for a number of standard reference materials were in good agreement with the certified values. 相似文献