Cloud point extraction of rare earths and zinc using 1,10-phenanthroline and Triton X-114 coupled with microwave plasma torch-atomic emission spectrometry
Abstract
In the present work, cloud point extraction (CPE) of rare earths and zinc coupled with microwave plasma torch-atomic emission spectrometry (MPT-AES) was studied with 1,10-phenanthroline as the chelating agent and polyethylene glycol tert-octylphenyl ether (Triton X-114) as the surfactant. The experimental parameters affecting the cloud point extraction, such as the aqueous phase pH, Triton X-114 concentration, 1,10-phenanthroline concentration, ionic strength, and equilibration time, were systematically studied and optimized. Effects of common coexisting ions on the determinations were also investigated. Under the optimum conditions, the calibration curves were linear over the concentration range of 0.005–5 μg mL−1. The limits of detection (3σ) were determined in the range of 0.3–1.0 μg L−1 with a relative standard deviation range of 2.4–4.1% (n = 7). The developed CPE-MPT-AES method was successfully validated by the recovery studies in real water and human urine and serum samples.