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流动注射在线萃取色谱预浓集火焰原子吸收法测定钯 总被引:6,自引:0,他引:6
以三异辛胺萃淋树脂为微型柱固定相,采用流动注射在线预浓集与火焰原子吸收法联用技术,对微量钯的测定进行了研究。在0.5mol/L的HCl介质中以7.8mL/min的速率采样90s再用0.1mol/L硫脲-0.5mol/L HCl洗脱;在27h^-1的采样频率下,浓集系数为50倍,浓集效率为22.5min,消耗指数0.23mL。线性范围为0-1000μg/L,检出限为0.34μg/L。钯含量水平50μg/L时,连续11次测定的相对标准偏差为2.6%,并对加氢催化剂中的钯进行了加标回收率实验,回收率为99.3%-101.2%。 相似文献
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流动注射壳聚糖在线微柱预富集火焰原子吸收光谱法测定痕量钯 总被引:4,自引:0,他引:4
报道了壳聚糖作在线微柱预富集柱填料,流动注射与火焰原子光谱联用(FI-FAAS)测定痕量Pd的方法。当采样体积13.5mL时,采样频率27/h,富集倍数49倍,线性范围0.01~0.4mg/L,检出限(3s,n=11)1.4μg/L,相对标准偏差1.26%(Cpd=0.2mg/L,n=11)和4.0%(Cpd=0.05mg/L)。初步探讨了该过程的吸附机理。将该方法用于催化剂样品中痕量Pd的测定,结果满意。 相似文献
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The preconcentration of Au and Pd on Duolite GT-73 chelating resin with the thiol functional group was investigated prior to determination of these noble metals by means of inductively coupled plasma atomic emission spectrometry. It was found that AuIII and PdII were retained on the resin along with other concomitant metals (Al, Ca, Cd, Co, Cr, Cu, Fe, Mg, Mn, Ni, Pb and Zn) from different HCl-containing media. A two-step elution procedure was developed for the release of the noble metals. First 4.0molL–1 HNO3 solution was used to elute the base metals. The recovery of Au and Pd was performed afterwards using 0.50molL–1 solution of (NH2)2CS. Retrieval of Au and Pd retained on Duolite GT-73 was also carried out by decomposition of the resin in the open vessel system using H2SO4 with H2O2. The detection limits of Au and Pd evaluated for the devised protocol, with a preconcentration factor of 50, were 0.085µgL–1 and 0.28µgL–1, respectively. The proposed method was applied to the determination of Au and Pd in spiked electrolytic bath samples. 相似文献
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《Analytical letters》2012,45(10):1562-1572
A rapid and sensitive method for the determination of trace levels of cadmium in cigarettes, soil, and blood samples by flame atomic absorption spectrometry (FAAS) has been developed. It is based on the online sorption of Cd(II) ions on a minicolumn packed by sodium dodecyl sulfate–coated alumina modified with dithizone. The optimum experimental parameters for the adsorption and desorption of cadmium were investigated. The recovery obtained was found to be 96% with preconcentration factor of 150. The calibration curve was linear between 50–600 µg/L Cd with a detection limit of 3 µg/L, sample frequency of 30 h?1 and reuse of column for 10 times without loss of sensitivity. The accuracy of the method was confirmed by applying the standard addition method and quantitative recoveries (95–99%) were obtained. 相似文献
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Valfredo Azevedo Lemos Ednilton Moreira Gama Adriana da Silva Lima 《Mikrochimica acta》2006,153(3-4):179-186
A new chelating sorbent has been developed using Amberlite XAD-2 resin anchored with pyrocatechol through the –CH2– group. This sorbent, characterised by elemental analysis and infrared (IR) spectra, was used as a packing material for a
minicolumn in an on-line preconcentration system for cadmium, cobalt and nickel determination. Metal ions were sorbed in the
minicolumn, from which it could be eluted directly to the nebulizer-burner system of the flame atomic absorption spectrometer
(FAAS). Metals can be eluted from the minicolumn with 0.50 mol L−1 HCl or HNO3. The enrichment factors were 22 (Cd), 23 (Co) and 25 (Ni), for 60 s preconcentration time, and 44 (Cd), 40 (Co) and 48 (Ni),
if 180 s preconcentration time was used. Under the optimum conditions, the procedure allowed the determination of cadmium,
cobalt and nickel with detection limits of 0.27, 0.59 and 1.29 μg L−1, respectively, when preconcentration periods of 180 s were used. The accuracy of the procedure was sufficient and evaluated
by analysing certified reference materials. The method was applied to the analysis of food samples (black tea and rice flour). 相似文献
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Cloud Point Preconcentration and Flame Atomic Absorption Spectrometric Determination of Cobalt and Nickel in Water Samples 总被引:2,自引:0,他引:2
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 相似文献
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A simple and reliable method for rapid and selective separation of trace amounts of Sr2+ ions from alkali and alkaline earth metal ions by using octadecyl silica membrane disks modified with decyl- 18-crown-6 in
the presence of 1.0 × 10−3 M picric acid is presented. The influence of picric acid concentration, flow rates and nature and amount of the stripping
acid have been investigated. Maximum capacity of the membrane disks modified with 10 mg of the macrocycle was found to be
484 μg of Sr2+ ions. The proposed method permitted enrichment factors of about 80 and higher. The limit of detection of the proposed method
is 1.5 μg per 1000 ml. The method was successfully applied to the recovery of Sr2+ ions from different synthetic and water samples.
Received August 10, 2000. Revision April 17, 2001. 相似文献
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建立了用分子印迹壳聚糖/凹凸棒石(MICA)分离富集-火焰原子吸收光谱(FAAS)测定痕量铅的新方法。 在动态吸附条件下,系统地研究了溶液pH值、流速、洗脱条件和干扰离子对痕量铅分离富集的影响;在pH=4.5,上样流速为0.60 mL/min的条件下,铅能被MICA定量富集;吸附的铅可用1.0 mol/L HCl-0.1 mol/L 甲基异丁酮的乙醇溶液在流速为0.96 mL/min条件下完全洗脱;在优化条件下,MICA对铅的动态吸附容量为36.78 mg/g。 线性范围为0~1.28 mg/L,r=0.999 7,检出限(3σ,n=11)为0.73 μg/L,相对标准偏差为1.69%(n=6,ρ=0.08 mg/L),回收率在98.7%~101.4%之间。 该方法操作简便、线性关系良好、灵敏度和精密度高,应用于实际水样中痕量铅的测定,结果满意。 相似文献
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Palladium was determined in pharmaceuticals by direct graphite furnace atomic absorption spectrometry (GFAAS) method. The detection limit was 0.1 μg/g in 5% solution; the recovery of 0.5–2.0 μg/g Pd spike was close to 100%. The flow injection GFAAS method was worked out using oxime and iminodiacetic acid ethyl cellulose (IDAEC) microcolumns for preconcentration of Pd in aqueous and 50% methanol solutions. The optimal pH range for preconcentration was 2–5. At 20-fold enrichment the detection limits for Pd were 0.39 μg/liter for oxime cellulose and 0.42 μg/liter for IDAEC. 相似文献
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With the aim of avoiding cumbersome sample treatment, we present a device for the introduction of solid soil samples into
AAS-flames for gold determination, as well as the proposition of earth from anthills as a gold occurrence indicator. A previous
ground sample of anthill earth (0.50 mg) was weighed directly into a small recipient of polyethylene which was then connected
to a sampling boronsilicate glass chamber. The sample was carried by an airflow (5 L min−1) to a quartz cell positioned between the burner top and the optical beam. The generated atomic vapor produced a transient
signal which was totally integrated in three seconds. The performance was compared with conventional flame atomic absorption
spectrometry after proper sample digestion. No significant differences were observed between both procedures (mean deviation
±1.90%), and a LOQ of 0.03 μg Au was achieved using the proposed method. The anthill earth was found to be very suitable for
indication of gold occurrence in soils and related materials. 相似文献
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报道了色谱301固载硫杂杯芳烃树脂分离预富集-火焰原子吸收光谱法测定痕量银的新方法。探讨了固载硫杂杯芳烃树脂对银的吸附原理与最佳条件。将含Ag^+试液在pH=10、温度为23±2℃的条件下恒温震荡10min,静置10min,Ag^+可被树脂定量富集被吸附的Ag^+可用5mL酸性硫脲(0.15mol/L HCl+0.15mol/L硫脲)完全洗脱,洗脱液中的银用火焰原子吸收光谱法测定。该法对银的检出限为0.17μg/L(3σ,n=11);线性范围为0.006—3mg/L。对0.18mg/L的Ag^+标液进行7次测定,RSD=1.53%。回收率在99.9%-105.0%之间。用于“二次资源”锌矿渣和环境水样中痕量银的测定,结果满意。 相似文献
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固载硫杂杯芳烃树脂分离富集-火焰原子吸收法测定痕量银 总被引:5,自引:0,他引:5
报道了色谱301固载硫杂杯芳烃树脂分离预富集-火焰原子吸收光谱法测定痕量银的新方法。探讨了固载硫杂杯芳烃树脂对银的吸附原理与最佳条件。将含Ag 试液在pH=10、温度为23±2℃的条件下恒温震荡10min,静置10min,Ag 可被树脂定量富集被吸附的Ag 可用5mL酸性硫脲(0.15mol/LHCl 0.15mol/L硫脲)完全洗脱,洗脱液中的银用火焰原子吸收光谱法测定。该法对银的检出限为0.17μg/L(3σ,n=11);线性范围为0.006~3mg/L。对0.18mg/L的Ag 标液进行7次测定,RSD=1.53%,回收率在99.9%~105.0%之间。用于“二次资源”锌矿渣和环境水样中痕量银的测定,结果满意。 相似文献
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A new method for the determination of trace cadmium in water samples by flame atomic absorption spectrometry (FAAS) after
cloud point extraction (CPE) is proposed. The method is based on the complexation of Cd with 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone
(PMBP) in the presence of non-ionic micelles of Triton X-100. The effect of experimental conditions such as pH, concentration
of chelating agent and surfactant, equilibration temperature and time on cloud point extraction was studied. Under the optimum
conditions, the detection limits are 0.64 ng mL±1 with relative standard deviations (RSDs) of 2.1% (n = 10). The proposed method was applied to the determination of trace
cadmium in water samples with satisfactory results. 相似文献
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《Analytica chimica acta》2003,481(2):283-290
In the present paper, an on-line system for preconcentration and determination of zinc by Flame Atomic Absorption Spectrometry (FAAS) is proposed. It is based in the sorption of zinc(II) ions on a minicolumn packed with polyurethane foam loaded with 2-[2′-(6-methyl-benzothiazolylazo)]-4-bromophenol (Me-BTABr) reagent. Chemical and flow variables as pH effect, sample flow rate and eluent concentration were optimized using univariate methodology. The results demonstrated that zinc can determinate using the sample pH in the range of 6.5-9.2, sample flow rate of 6.0 ml min−1, and the elution step using 0.10 mol l−1 hydrochloric acid solution at flow rate of 5.5 ml min−1. In these conditions, an enrichment factor of 23 and a sampling rate of 48 samples per hour were achieved. The detection limit (DL, 3σ) as IUPAC recommendation was 0.37 μg l−1 and the precision (assessed as the relative standard deviation, R.S.D.) reached values of 5.9-1.8% in zinc solutions of 1.0-10.0 μg l−1 concentration, respectively. The method was successfully applied to the determination of trace amounts of zinc in natural water samples from Salvador (Brazil). 相似文献
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提出了纳米硅羟基磷灰石(Si-HAP)分离富集,火焰原子吸收光谱法(FAAS)测定水样中痕量铅的新方法。考察了铅在纳米Si-HAP上的吸附动力学、最佳酸度和吸附容量。实验结果表明:在最佳实验条件下,纳米Si-HAP能定量、快速地吸附水中的痕量Pb2+,其静态吸附容量24.33 mg/g;吸附在纳米Si-HAP上的Pb2+可用0.01mol/L EDTA-Ca完全洗脱。本法对Pb2+的检出限为1.33 ng/mL,相对标准偏差为4.0%(n=11,c=1μg/mL),加标回收率在94.9%~102.0%之间。方法用于实际水样中铅的测定,结果满意。 相似文献
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This paper demonstrates the potential of two natural adsorbents, vermicompost and humic acid, for preconcentration of cadmium(II) and lead(II) using flow systems coupled to flame atomic absorption spectrometry (FAAS). The procedure involves the adsorption of Cd(II) or Pb(II) on these materials (using columns containing 25mg) and subsequent elution for determination by FAAS. Cadmium(II) was preconcentrated for 4min (flow rate of 4.0mLmin–1) and eluted with 220µL of 3.0molL–1 HNO3. Under these conditions, preconcentration factors of 46 and 27 were obtained for vermicompost and humic acid, respectively. Except when using 1.0molL–1 nitric acid (for humic acid), all conditions for lead(II) preconcentration were identical to those for cadmium(II), and preconcentration factors of 62 and 83 were obtained when vermicompost and humic acid, respectively, were used. The systems were stable with only slight variations in the slopes of the analytical curves (ca. 5% after 8h working period). The long-term stability shows that a minimum of 120 and 100 cycles, respectively, can be run using the same masses of vermicompost or humic acid. The detection limits for Cd(II) were 0.4 and 0.8µgL–1 for vermicompost and humic acid respectively, while the detection limits for Pb(II) were 8.8 and 12.1µgL–1, also for vermicompost and humic acid. The accuracy of the methods was checked by using spiked and real (certified and reference) samples. Due to the concomitant sorption of other metals leading to variable slopes for lead and cadmium determination, it was necessary to adopt the standard addition method for calibration purposes. 相似文献