Sorption–luminescence method for determination of europium using acid-modified clinoptilolite

Abstract

Sorption–luminescent method for europium determination based on the acid-modified Transcarpathian clinoptilolite without using toxic organic solvents was proposed. Optimal luminophore preparation condition is the sorption of Eu(III) on the precalcined at 400 °C H-clinoptilolite, in the solution with pH 9.5. The obtained H-clinoptilolite–Eu(III) sample, precalcined at 50 °C, was treated with 1,10-phenanthroline, atophan, and urotropine solutions. For luminescence excitation, the rays with wavelength of λ = 276 nm were used. Luminescence intensity at λ = 615 nm was selected as an analytical parameter for a europium quantitative determination. Linear calibration range of Eu(III) concentration with the detection limit of 3 ng mL−1 is within 10–900 ng mL−1. The proposed method can be used for europium determination in the presence of many rare earths. Sorption–luminescent method can be applied for the determination of europium ions trace amounts in synthetic water solutions. The proposed analytical method gave recoveries from 95 to 102% and RSD from 3.5 to 7.9% during the determination of europium.