determination of rhodium(iii) ions by flame atomic absorption spectrometry after preconcentration with modified magnetic activated carbon

a new method for analysis of trace amount of rh(iii) ions by magnetic activated carbon modified with 2,3,5,6-tetra(2-pyridyl)pyrazine (mac/tppz) as the magnetic sorbent has been proposed. the proposed adsorbent was found to be advantageous over conventional solid phase extraction (spe) in terms of operational simplicity and low time-consuming. the experimental parameters affecting the extraction/preconcentration and determination of the analyte were systematically examined. in order to investigate the selectivity of this magnetic sorbent, the effect of a variety of ions on preconcentration and recovery of rh(iii) ions were also investigated. under optimum conditions, the calibration graph was linear for the concentration range of 0.8-650 µg l-1. the limit of detection (lod, 3sb/m) and the relative standard deviation (rsd, n = 8, c = 50 µg l-1) were 0.1 µg l-1 and 3.6%, respectively. the maximum sorption capacity of the adsorbent for rhodium was found to be 21.6 mg g-1. the presented procedure was applied to monitoring rhodium in water and synthetic samples.