Automated On-line Preconcentration System for Electrothermal Atomic Absorption Spectrometry for the Determination of Copper and Molybdenum in Sea-water

absorption spectrometry was developed. The performance of retain transition metal ions. After the sample loading step, the the on-line preconcentration system was tested by determining metal ions are stripped from the column with a suitable eluent Cu and Mo in sea-water. Calibration graphs constructed from and directly injected into the nebulizer of a flame atomic the preconcentration of standards in 0.2% 3 solution were absorption or a plasma emission spectrometer for detection. used. On-line preconcentration is computer-controlled. A On-line preconcentration systems are better than o -line batch miniature Muromac A-1 resin column was inserted at the tip preconcentration methods, because the former are more of the AS-60 autosampler arm. A modification of the AS-60 e cient, reproducible, easily automated, have low consumption autosampler in the tubing line and circuit allowed either flow of sample and reagent and low risk of contamination.18On-line of the sample through the column or operation of the flow injection column preconcentration in atomic spectrometry autosampler in the normal mode. Retention of the metal ions was reviewed by Fang et al.19 The on-line column preconcenas complexes on the microcolumn was achieved by using tration systems with liquid delivery forced by air o er a Muromac A-1 as the chelating resin; 20% v/v 3 was then number of advantages:20–22 ease of automation; lower conused for elution. With a 198.6 ml sample loop, the throughput sumption of reagent; reduced risk of contamination; and the is 14 samples h−1. Detection limits are 0.009 mg l−1 for Cu peristaltic pump can be used as the air drive. Beinrohr et al.20 (606.9 ml sample loop) and 0.06 mg l−1 for Mo (50 ml sample were the first to introduce air transportation of sample/eluent loop and repeated four times). The accuracy of the method streams obtained from the air support of the atomic absorption was confirmed by the analysis of certified reference saline spectrometer. Azeredo et al.21 introduced the peristaltic pump waters. as the air drive and integrated column preconcentration with