Quantification of Pb, Cd and Hg in Waste Rare Earth Phosphors from Abandoned Fluorescent Lamps and Cathode Ray Tubes by ICP-OES

A fast and simple method to allow routine analysis of waste phosphors was developed and fully validated. Pb, Hg in waste fluorescent lamps phosphors (WFP) and Pb, Cd in waste CRT phosphors (WCP) were quantified by inductively coupled plasma atomic emission spectrometry (ICP-OES). Analytical conditions, including choice of analytical spectral lines, sample dissolution methods and many other standards, were studied. Wavelengths of 220.353, 228.802, and 184.886 nm were selected as analytical lines for determination of Pb, Cd, and Hg respectively. Studies showed that, Nitric acid could be used for dissolving Cd and Hg, and alkali fusion method for Pb. Detection limits of Pb, Cd, and Hg found were 1.8, 0.3 and 3mg/kg respectively. The proposed method was used in determination of target elements in waste rare earth phosphors, giving values of recovery in the ranges of 96.5%-104%, 98.5%-105% for Pb, Hg in WFP, and 98%-104.5%, 98%-104.5% for Pb, Cd in WCP respectively, and values of RSD less than 8%. Also, influences by dilution factor, coexisting elements and HNO3 Concentration etc. were discussed in the paper.