On‐Line Selective Solid‐Phase Extraction of Copper with a Surface Ion Imprinted Silica Gel Sorbent

Copper(II)-ion imprinted silica gel (Cu-IISG) sorbent was synthesized by surface imprinting technique and was employed as a selective solid-phase extraction material for on-line preconcentration and separation, then coupled with atomic absorption spectrometry (AAS) determination of Cu(II). The higher selectivity coefficient of Cu-IISG for Cu(II) in the presence of competitive ions such as Fe(III), Ni(II) and Zn(II) was above 411, which was 35 times of NISG. The static adsorption capacity and dynamic adsorption capacity were 41.11 mg g -1 and 16.20 mg g -1 , respectively. The Cu-IISG offered a fast kinetics for the adsorption and desorption of Cu(II), which can be used for on-line preconcentration and detection. Two certified reference materials of GBW07301a sediment and GBW07401 soil were analyzed and the determined values were in a good agreement with the certified values. The developed method was also successfully applied to the determination of trace copper in tea leaf with satisfactory results (recovery between 96.3% and 102.3%).