scholarly journals A fully automated flow injection atomic absorption system for the determination of copper traces in waters with on-line pre-concentration in an ion-exchange column

1995 ◽  
Vol 17 (1) ◽  
pp. 25-29 ◽  
Author(s):  
J. L. Burguera ◽  
M. Burguera ◽  
P. Carrero ◽  
J. Marcano ◽  
C. Rivas ◽  
...  

The paper describes the development of an automatic on-line column pre-concentration technique using a time based-flow injection atomic absorption spectrometry system. A manifold incorporating a micro-column containing 25 mg of Dowex 50W-X8 was used with a time-based injector for the pre-concentration and determination of copper in natural and drinking waters. The system features depend on the alternate positions of a solenoid valve. The 3σ detection limits, enrichment factors, sampling frequency, relative standard deviations and linear calibration graphs were, respectively, in the range 0.6-1.5 μg/l, 25-60, 15-30 measurements/h, 1.0-3.1% and 1-65 μg/ml for pre-concentration times of 1 min. The procedure was successfully applied to a range of water samples and the accuracy was assessed through recovery experiments, the analysis of certified reference water samples and by independent analysis by atomic absorption spectrometry with electrothermal atomization.

2002 ◽  
Vol 85 (6) ◽  
pp. 1410-1414 ◽  
Author(s):  
Ricardo Fernández Orsi ◽  
Rodolfo G Wuilloud ◽  
Jorgelina C A de Wuilloud ◽  
Roberto A Olsina ◽  
Luis D Martinez

Abstract An on-line cadmium preconcentration and determination system implemented with flame atomic absorption spectrometry (FAAS) associated with flow injection was studied. Cadmium was retained as Cd-2-(5-bromo-2-pyridylazo)-5-diethylaminophenol Cd-(5-Br-PADAP) complex, pH 9.3. The Cd complex was removed from the knotted reactor (KR) with ethanol. A total enhancement factor of 140 was obtained with respect to FAAS (40 for KR and 3.5 due to the use of ethanol) with preconcentration time of 120 s. The detection limit value for preconcentration of 1 g sample was 0.5 ng/g. The repeatability for 10 replicate determinations at 5.0 ng/g Cd level was 3.5% relative standard deviation, calculated from peak heights obtained. The calibration graph using the preconcentration system for Cd was linear with a correlation coefficient of 0.9990 at levels near the detection limits to at least 2000 ng/g. The method was successfully applied to determination of total Cd in honey samples.


2003 ◽  
Vol 86 (4) ◽  
pp. 839-845 ◽  
Author(s):  
Peng Liu ◽  
Qiaosheng Pu ◽  
Qiaoyu Sun ◽  
Zhixing Su

Abstract A simple and highly selective method was developed for the routine determination of trace or ultratrace amounts of gold and palladium in geological and metallurgical samples. The method uses flow injection on-line preconcentration and separation with determination by flame atomic absorption spectrometry. Au and Pd in the sample are adsorbed on a 2-mercaptopyrimidine chemically modified silica gel (MPMSG) packed microcolumn in a 0.50M HCl medium and then eluted with 0.5 or 1.0% thiourea solution. The eluates are introduced into the flame atomic absorption spectrometer directly. With the use of a 0.85 mL microcolumn (about 0.14 g MPMSG packed), the present system tolerated concentrations of common base metal ions up to 25.0 mg/mL and concentrations of anions up to 100.0 mg/mL when Au(III) at 0.100 μg/mL and Pd(II) at 0.200 μg/mL were preconcentrated for 60 s with a sample flow rate of 5.0 mL/min. The limits of detection were 3.1 ng/mL for Au(III) and 6.1 ng/mL for Pd(II) with relative standard deviations of ≤2.5%. The analytical results obtained by the proposed method for geological and metallurgical samples were in good agreement with the certified values.


Sign in / Sign up

Export Citation Format

Share Document