Sorption of a complex of europium (III) with acetylacetone on hydrophobized hexadecyl silica gel and hyper crosslinked polysterene

The sorption of a complex of europium (III) with acetylacetone on silica gel chemically modified with hexadecyl groups (SiO2-C16) and hyper crosslinked polystyrene (HLPS) was studied. Maximum extraction was observed at pH 5-7 when SiO2-C16 was used as the sorbent and at pH 4-7 in the case of crosslinked polystyrene. The partition coefficients for HLPS and silica gel were calculated as 7 × 103 and 1 × 102 cm3/g, respectively. Quantitative extraction of the europium (III) complex was possible in dynamic conditions using a microcolumn (length, 10 mm; internal diameter, 3mm) packed with HLPS at pH 5 (10-50 mL sample volume). Desorption of europium using solutions of nitric acid at different concentrations was investigated. Quantitative desorption was achieved using 5 mL of 1 M HNO3. A linear range of detection was observed at an amount of europium from 5 to 25 μg in a 10-mL sample (650 nm). © 2013 Allerton Press, Inc.