Solid phase extraction of gold(III) on attapulgite modified with triocarbohydrazide prior to its determination in environmental samples by ICP-OES.

The first study on the high efficiency of triocarbohydrazide modified attapulgite as solid-phase extractant for preconcentration of trace Au(III) prior to the measurement by inductively coupled plasma optical emission spectrometry (ICP-OES) has been reported. Experimental conditions for effective adsorption of trace levels of Au(III) were optimized with respect to different experimental parameters using batch and column procedures in detail. At pH 3, Au(III) could be quantitatively adsorbed on the new sorbent, and the adsorbed Au(III) could be completely eluted from the sorbent surface by 2.0mL 1.0molL(-1) of HCl+2% CS(NH(2))(2) solution. An enrichment factor of 150 was accomplished. Moreover, common interfering ions did not interfere in both separation and determination. The maximum adsorption capacity of the sorbent for Au(III) was found to be 66.7mgg(-1). The detection limit (3σ) of this method was 0.32μgL(-1) and the relative standard deviation (RSD) was 3.3% (n=8). The method, with high selectivity, sensitivity and reproducibility, was validated using certified reference materials, and had been applied for the determination of trace Au(III) with satisfactory results.