Determination of Rhodium(III) Ions by Flame Atomic Absorption Spectrometry after Preconcentration with Modified Magnetic Activated Carbon

Abstract

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, 3S<em>_b/m</em>) and the relative standard deviation (RSD, <em>n </em>= 8, <em>c </em>= 50 µg l^-1) were 0.1 µg l^-1and 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.