FERROSPECTRAL SORBED ON DEAE SEPHADEX A-25 FOR THE SOLID PHASE SPECTROPHOTOMETRIC DETERMINATION OF IRON AND COBALT BY BATCH AND CONTINUOUS FLOW MODES

摘要

In this work, Ferrospectral;3-(2-pyridyl)-5,6-bis(4-phenylsulfonic acid)-1,2,4-triazine (FST) sorbed on DEAE Sephadex A-25 is used as solid phase for spectrophotometric determination of iron and cobalt by batch and continuos flow modes. In batch simultaneous determination, the second derivative at 536.0 and 601.4 nm were used for iron and cobalt determination, respectively. In this modality, the detection limits (3 o criterion), for iron and cobalt were 1.3, 9.1, ug L1 and the determination ranges were: 4.3 to 220 and 30.3 to 800 ug L1. The method by FIA mode was carried out by stopped flow and then the analytical signal was evaluated by second derivative at 560.9 and 482.3 nm for iron and cobalt determination; respectively. In FIA modality, the detection limits for iron and cobalt were 6.4, 31 ug L1, and the determination ranges 21 to 200 and 106 to 1000 ug L1 iron and cobalt, respectively. In both modalities the repeatability for iron and cobalt were 4 % and the recovery was near to 100%. These methods were applied successfully in drinking water and soil samples.