Determination of Lead(II) in Water by FIA of Pb(II)-XO-CTMAB

Make xylenol orange as chromogenic reagent,and which react with lead to a ternary complex in CTMAB,building a new flow injection spectrophotometry method which is high sensitivity,high efficiency to tested lead content in water.Chemicals and physicals had been optimized in detail,the stability,precision and linear range of the instrument had been studied,and effects of various interfere ions on sensitivity had been investigated.The method provides a linearity range over 8 to 2000 μg.L-1,and the linearity equation was: ΔA = 0.1526(Pb2+ /μg.L-1) +4.1519,r2 = 0.9991,linear relationship is good.The detection limit estimated(3σ) was 2.96 μg.L-1.The relative standard deviation(RSD) calculated from 10 times at 400 μg.L-1 repeated injection was 1.53% and instrument have a good stability.The determination results of water samples were consistent with that of GB,and the recoveries were between 98.6% and 102.5%,the proposed method is pratical.