Selective separation of gadolinium from a series of f-block elements by cloud point extraction and its application for analysis of real samples

A selective and effective cloud point extraction procedure was presented for separation of Gd3+ from other f-block elements (i.e. La3+, Ce3+, Nd3+, Sm3+, Ho3+, Er3+ , Th (4+) and U6+). The procedure depends on the formation of stable hydrophobic complex between Gd3+ and quercetin at pH 3.0. The formed complex was extracted at room temperature into surfactant rich phase Triton X-114 in the presence of 0.1 mol L-1 KI. The procedure was also used for enrichment of Gd3+ prior its determination by ICP-OES. At optimum conditions, the proposed procedure displays good analytical linearity (0.1-200 mu g L-1) with limit of detection and limit of quantification of 0.03 and 0.11 mu g L-1, respectively. The enrichment factor was 49.2 for 50 mL sample. The analyte was quantitatively tolerated in the presence of most concomitant ions. The procedure was then employed for the analysis of Gd3+ in ore, urine and synthetic samples.