Biosorption of Cd+2, Cu+2, and Ni+2 Ions by a Thermophilic Haloalkalitolerant Bacterial Strain (KG9) Immobilized on Amberlite XAD-4

摘要

A newly isolated thermophilic haloalkalitolerant bacterial strain (KG9) as immobilized cells on a solid support was presented as a new biosorbent for the enrichment of Cd(II), Cu(II), and Ni(II) prior to flame atomic absorption spectrometric analysis. The KG9 strain was identified as a close member of Bacillus licheniformis following complete sequencing of 16S rRNA. The optimum conditions such as pH, amount of adsorbent, eluent type and volume, flow rate of sample solution, volume of sample solution, and matrix interference effect on the retention of the metal ions were evaluated for the quantitative recovery of the analytes. The analyte ions were quantitatively recovered and desorbed at pH range of 6.0-7.0 and 5 mL of 0.5 mol.L-1 HCl. The loading capacities of adsorbents for Cd(II), Cu(II), and Nip were found to be 22.7, 61.1, and 33.4 mu mol.g(-1) respectively. The analytical detection limits for cadmium(II), copper(II), and nickel(II) were 0.42 mu g.L-1, 0.54 mu g.L-1, and 1.24 mu g.L-1. The proposed procedure was applied for the determination of metal ions in river water, drinking water, and mushrooms. The accuracy of the developed procedure was tested by analyzing NRCC-SLRS4 riverine water and SRM1570a spinach leaves as the certified reference materials.