Selective solid phase extraction of trace Sc(III) from environmental samples using silica gel modified with 4-(2-morinyldiazenyl)- N-(3-(trimethylsilyl)propyl)benzamide

Abstract

In this study, a new 4-(2-morinyldiazenyl)- N-(3-(trimethylsilyl)propyl)benzamide modified silica gel (SG-MTPB) sorbent was prepared and characterized by FT-IR spectroscopy and studied for separation and preconcentration of Sc(III) prior to its determination by inductively coupled plasma atomic emission spectrometry (ICP-AES). Experimental conditions for effective adsorption of trace Sc(III) were optimized using both batch and column procedures. At pH 3, Sc(III) could be quantitatively adsorbed on the new sorbent. And the adsorbed Sc(III) could be completely eluted by using 2 mL of 6 mol L −1 of HCl + 2% CS(NH 2) 2. Most common coexisting ions did not interfere with the separation and preconcentration of Sc(III) at optimal conditions. The maximum static adsorption capacity of the sorbent for Sc(III) was 600 μmol g −1 while the time of 95% adsorption was less than 2 min. The detection limit of present method was found to be 0.085 μg g −1, and the relative standard deviation (R.S.D.) was lower than 1.3%. The method was also successfully applied to the preconcentration of trace Sc(III) in the environmental samples with satisfactory results.