1-亚硝基-2-萘酚浊点萃取-火焰原子吸收光谱法对水样中痕量铁的测定

采用以1-亚硝基-2-萘酚为螯合剂、Triton X-114为表面活性剂的新型浊点萃取体系富集水中的痕量铁,并用火焰原子吸收光谱法对铁进行测定。详细探讨了溶液pH值、表面活性剂浓度、络合剂浓度、平衡温度、平衡时间等对浊点萃取及测定灵敏度的影响,优化了实验条件。在最佳条件下测得铁的检出限（S／N=3）为0．42μg·L^-1,富集倍数为32,校准曲线相关系数为0．996。应用该法测定海水、湖水及自来水中的痕量铁,结果满意。     

Cloud Point Preconcentration and Flame Atomic Absorption Spectrometric Determination of Cobalt and Nickel in Water Samples

 Cloud point methodology was successfully used to preconcentrate trace amounts of Co and Ni as a prior step to their determination by flame atomic absorption spectrometry. 1-Nitroso-2-naphthol and polyethylene glycol-p-nonylphenylether (PONPE 7.5) are used as hydrophobic ligand and nonionic surfactant, respectively. Optimization was performed of the variables effecting complexation and phase separation. Additionally, the influence of viscosity on the analytical signal was investigated. Under the experimental conditions used, preconcentration of only 10 mL of sample in the presence of 0.075% (v/v) PONPE 7.5 permitted the detection of 1.09 μg L⁻¹ of Ni and 1.22 μg L⁻¹ of Co with enhancement factors of 29 and 27 for Ni and Co, respectively. The relative standard deviations (n=5) at concentrations of 80 and 50 μg L⁻¹ for Co and Ni were 2.53 and 2.89%, respectively. Good recoveries in the range of 96–105% were obtained for spiked samples. The effect of different interferent species was studied. The proposed method was applied to the determination of Ni and Co in different water samples. Correspondence: Department of Analytical Chemistry, Faculty of Chemistry, Tabriz University, Tabriz, Iran. e-mail: manzoori@tabrizu.ac.ir Received September 1, 2002; accepted November 8, 2002     

浊点萃取-火焰原子吸收光谱法测定样品中的痕量钴

研究了基于表面活性剂Triton X-114和络合剂吡咯烷二硫代氨基甲酸铵（APDC）浊点萃取钴的样品前处理方法.优化了浊点萃取条件参数,包括pH值、Triton X-114用量、APDC浓度、平衡温度及时间等,建立了浊点萃取-火焰原子吸收光谱法测定痕量钴的方法.该法的检测限（3σ）为2.6μg/L,相对标准偏差RSD为6.2%（n=7,c=200μg/L）.该法成功地应用于海带、维生素B12注射液等样品中钴的测定.     

浊点萃取预富集火焰原子吸收光谱法测定水样中痕量钴

本文提出了浊点萃取预富集火焰原子吸收光谱法测定痕量钴的新方法。详细研究了溶液pH值、络合剂和表面活性剂浓度、平衡温度和时间等条件对浊点萃取效果的影响。在优化的实验条件下,本法对钴的富集倍数为20倍,检出限为3．28ng／mL,相对标准偏差(RSD)为4．1％(n=10)。所建立的方法用于自来水、湖水中痕量钴的测定,分析结果满意。     

浊点萃取-石墨炉原子吸收光谱法测定环境样品中的镉

建立了浊点萃取分离富集石墨炉原子吸收光谱法测定环境样品中痕量镉的方法.浊点萃取选择8-羟基喹啉为螯合剂,Triton X-100为表面活性剂.在pH 8～9、0.01%8-羟基喹啉和0.2%-Triton X-100、80 ℃水浴20 min的优化条件下,所建立方法的检出限为2.5 ng/L; 加标回收率为94.6%～106.2%; 对样品溶液进行富集的富集因子为17.利用该方法分别测定了2个实际水样和2个国家标准参考物质中的总镉含量,结果令人满意.     

Determination of Ultratrace Amounts of Copper（ Ⅱ ） in Water Samples by Electrothermal Atomic Absorption Spectrometry After Cloud Point Extraction

IntroductionIn environment, copper is usually found in traceor ultratrace levels, and its detection requires sensitiveinstrumental measuring techniques such as electrother-mal atomic absorption spectrometry(ETAAS) and ICP-AES or ICP-MS. Frequently, a prec…     

浊点萃取-火焰原子吸收光谱法测定矿渣中痕量金

研究了以双硫腙为络合剂,以非离子型表面活性剂Triton X-100为萃取剂的浊点萃取-火焰原子吸收光谱法(CPE-FAAS)测定痕量金(Ⅲ)的新方法。详细考察了溶液的pH值、络合剂和表面活性剂浓度、平衡温度和时间等条件对浊点萃取效果的影响。该方法的线性范围为0.05~0.8μg/mL,检出限为7.9 ng/mL,相对标准偏差为4.12%(n=11),回收率在98.0%~102.0%之间,用于矿渣中金的测定,结果满意。     

Selective Determination of Copper in Water Samples by Atomic Absorption Spectrometry after Cloud Point Extraction

A preconcentration methodology utilizing the cloud point phenomenon is described for the determination of copper by flame atomic absorption spectrometry. The reagent Sulfathiazolylazo resorsin was used as a complexing agent. The preconcentration factor of 25-fold was obtained. The calibration curve is linear in the range of 4–400 µ g L^?1 with a limit of detection of 0.64 µ g L^?1. The relative standard deviation (n = 5, 12 µ g L^?1) was 3.5%. The cloud point is formed in the presence of phenol at room temperature. The method was successfully applied to the determination of copper in water samples and a standard reference material.     

浊点萃取-石墨炉原子吸收光谱法测定环境样品中的痕量镉

研究了浊点萃取-石墨炉原子吸收光谱法(GFAAS)测定痕量镉的新方法,利用表面活性剂Triton X-100和络合剂1-(2-吡啶偶氮)-2-萘酚(PAN)对镉进行浊点萃取。详细探讨了影响浊点萃取及测定灵敏度的因素。优化条件为:0.25 mL 30%NaC l,pH 8.5,0.50 mL、4.0×10-4mol/L PAN,0.2 mL 1.0%TritonX-100。在最佳条件下,镉的富集倍率为50倍,检出限为5.9 ng/L,RSD为2.1%。该方法用于环境样中痕量镉的富集和测定,结果令人满意。     

煤中镓的火焰原子吸收光谱法测定

煤试样灰化后,经碱熔、酸浸,在乙酸丁酯-四丁基氯化铵萃取后用乙二胺四乙酸热溶液萃取,在6 mol·L-1 HCl介质中用火焰原子吸收光谱法(FAAS)测定镓.该方法的检出限为0.030 mg/L(S/N＝3,n＝11),样品的加标回收率为95% ～102%,RSD在3.4% ～6.0%范围内.用该法测煤样品中微量镓,结果满意.     

Solid Phase Extraction and Flame Atomic Absorption Spectrometric Determination of Trace Amounts of Zinc and Cobalt Ions in Water Samples

A simple and rapid method for the preconcentration of Co²⁺ and Zn²⁺ as their 2-guanidino-benzimidazole chelates is proposed using an octadecyl silica cartridge. The retained analytes were recovered with a mixture of 5mL of 0.01M HNO₃ and 5mL of methanol. The metal ions in the effluent were determined by flame atomic absorption spectrometry. The effect of different parameters, such as sample matrix, amount of ligand, type of eluent for elution of ions from cartridge, flow rates of sample solution and eluent, breakthrough volume, and limit of detection, were evaluated. The effects of various cationic and anionic interferences on the percent recovery of Co²⁺ and Zn²⁺ were also studied. Quantitative extraction efficiencies were obtained by elution of the cartridge with a minimal amount of solvent. Hence, with a typical preconcentration factor of 50, the limits of detections of the proposed method are 0.26 and 1.62ngmL^–1 for Zn²⁺ and Co²⁺, respectively. The method was applied to the determination of zinc and cobalt ions in different water samples.     

Determination of Ultratrace Amounts of Copper(Ⅱ) in Water Samples by Electrothermal Atomic Absorption Spectrometry After Cloud Point Extraction

A novel approach was developed for the determination of ultratrace amounts of copper in water samples by using electrothermal atomic absorption spectrometry (ETAAS) after cloud point extraction (CPE). 1-( 2-Pyridylazo)-2-naphthol was used as the chelating reagent and Triton X-114 as the micellar-forming surfactant. CPE was conducted in a pH 8.0 medium at 40 ℃ for 10 min. After the separation of the phases by centrifugation, the surfactant-rich phase was diluted with 1 mL of a methanol solution of 0. 1 mol/L HNO3. Then 20 μL of the diluted surfactant-rich phase was injected into the graphite furnace for atomization in the absence of any matrix modifier. Various experimental conditions that affect the extraction and atomization processes were optimized. A detection limit of 5 ng/L was obtained after preconcentration. The linear dynamic range of the copper mass concentration was found to be 0-2.0ng/mL, and the relative standard deviation was found to be less than 3.1% for a sample containing 1.0 ng/mL Cu(Ⅱ). This developed method was successfully applied to the determination of ultratrace amounts of Cu in drinking water, tap water, and seawater samples.     

Determination of Hg(II) in Environmental Water Samples by Dispersive Liquid Phase Microextraction Combined with Flame Atomic Absorption Spectrometry

In this study, a method of dispersive liquid phase microextraction combined with the flame atomic absorption spectrometry was proposed for the determination of trace Hg using diphenylthiocarbazone as chelating reagent. Several factors which have effect on the microextraction efficiency of Hg, such as pH, extraction and dispersive solvent type and their volume, concentration of the chelating agent, extraction time were investigated, and the optimized experimental conditions were established. After extraction, the enrichment factor was 68. The detection limit of the method was 45 ng mL^?1, and the relative standard deviation for eight determinations of 2 μg mL^?1 Hg was 1.7%. The results for the determination of Hg in environmental water samples (tap water, well water, mineral water and Caspian sea water) have demonstrated the applicability of the proposed method.     

Preconcentration and Determination of Tin in Water Samples by Using Cloud Point Extraction and Graphite Furnace Atomic Absorption Spectrometry

A method based on cloud point extraction and graphite furnace atomic absorption spectrometry (GFAAS) was developed for the analysis of trace tin in water samples. After cloud point extraction, the tin in the water samples was preconcentrated and successfully separated from most interferents. During the procedure, 8-hydroxyquinoline (8-HQ) was used as chelating reagent, and Triton X-114 was added as surfactant. The parameters affecting the sensitivity and the extraction efficiency, such as solution pH, concentration of 8-HQ and Triton X-114, equilibration temperature and centrifuge time, were evaluated and optimized. Under the optimum conditions, a preconcentration factor of 96.2 was obtained for a 20 mL water sample. The detection limit (LOD) was as low as 0.012 ng mL⁻¹, and the analytical curve was linear in the range of 0.05–2.0 ng mL⁻¹ with satisfactory precision (RSD <4.1%). The proposed method was successfully applied to the determination of trace tin in water samples with recoveries in the range of 85.0–112.0%.     

Synergistic Extraction and Atomic Absorption Spectrometric Determination of Managanese in Environmental Samples Using M-p-Aminophenyl-2-Furylacrylohydroxamic Acid and Trioctylmethylammonium Cation

Abstract

Fifteen new hydroxamic acids were explored in conjunction with trioctyimethylammonium cation for the extractive separation of manganese into MIBK from the anions and cations commonly associated with the metal in environmental samples. The most rapid extraction with the maximum selectivity and sensitivity for the atomic absorption spectrometric determination of the metal in the MIBK extract was achieved with N-p-aminophenyl-2-furylacrylohydroxamic acid. The method enabled the determination of manganese at sub-ppb levels and was applied in the analysis of coal, manganese ore, plant tissue, animal tissue and natural waters.     

Atomic Absorption Spectrometric and Spectrophotometric Trace Analysis of Indium in Environmental Samples

Abstract

Indium (III) was selectively extracted at pH 5.2–5.9 with N-p-methoxyphenyl-2-furylacrylohydroxamic acid (MFHA) into chloroform. BPAR [5-bromo-4(2-pyridylazo) resorcinal] was added to the extract to form an intensely red coloured ternary complex measurable spectrophotometrically at 515 nm (? = 5.81 × 10⁴ 1 mol^?1 cm^?1). The extraction system enabled enrichment of indium and determination of the metal down to 10^?4 ppm (0.1 ppb) levels. For atomic absorption spectrometric determination, indium was extracted with MFHA into methyl isobuyl ketone and measured at 303.9 nm resonance line in the air-acetylene flame. Both the methods were     

火焰原子发射法测定食品和水样中锶

锶是人体必需的微量元素[1] ,它与人类健康密切相关。锶是人体骨骼及牙齿的正常组成成分 ,有助于降低心血管疾病的死亡率 ,调节神经及肌肉的兴奋性。因此测定食品和水样中锶有着重要意义。目前 ,锶的测定方法有 ICP法[2 ,3] 、火焰原子吸收光谱法 [4 ,5]和石墨炉原子吸收光谱法 [5,6]等。采用原子发射法测定未见报道。本文研究了以乙炔 -空气火焰原子发射法测定食品和水样中锶。试验表明 ,采用适当的测定条件 ,在样液中同时加入乙二胺四乙酸二钠和镧溶液 ,有效地抑制了干扰离子对测定的影响 ,方法经分析标准参考物质 ,结果吻合 ,该法简便…     

Flame Atomic Absorption Spectrometric Determination of Cu(II), Co(II), Cd(II), Fe(III) and Mn(II) in Ammonium Salts and Industrial Fertilizers after PrEconcentration/Separation on Diaion HP-20

A sensitive and simple separation-enrichment technique for the determination of trace amounts of Cu(II), Co(II), Cd(II), Fe(III) and Mn(II) was described. Metal ions were complexed with 1-nitroso-2-naphthol at pH 9. Following solid-phase extraction on Diaion HP-20 resin, metals were determined by flame atomic absorption spectrometry. The effect of the matrix ions were investigated. The recoveries of metal ions were greater than 95%. The detection limits of the analyte ions ( k = 3, N = 21) were varying 0.18 µg/l for Cd(II) to 0.44 µg/l for Fe(III). The method was applied to a stream sediment standard reference material (GBW7309), some ammonium salts and industrial fertilizer samples for the determination of copper, cobalt, cadmium, iron and manganese. The relative standard deviations (RSD) of the determinations for analyte ions at µg/g levels varied from 1 to 10%.