【摘要】 本文研究了流动注射在线编结反应器吸附预富集火焰原子吸收测定痕量铅的体系。在线生成的二乙基二硫代氨基甲酸铅螯合物被吸附在反应器内壁，然后由甲基异丁基酮洗脱并直接输送至火焰原子化器。新设计了颇具特点的一泵一阀自动预富集流路。经40s预富集，测定铅的灵敏度提高32倍，检测限达2．9μg／L。40μg／L和200μg／L铅10次测定的相对标准偏差（RSD）分别为1．4％和1．0％。加入0．5％抗坏血酸，0．1％邻菲啰啉，1％硫脲混合掩蔽剂可以消除1mg／LCu2＋、50mg／LFe3＋等常见离子的干扰。所建立的方法已用于水样中痕量铅的测定。更多还原

【Abstract】 A flow injection on-line adsorptive preconcentration system with a knotted reactor (KR) for flame atomic absorption spectrometric (FAAS) determination of trace lead was developed. The on-line formed lead chelate of diethyldithiocarbarmate was adsorbed on the inner wall of a KR made of PTFE tubing. The sorbed lead species was eluted with methyl isobutyl ketone and directly transported to the nebulizer of FAAS. A new design manifold allowed for a system of one peristaltic pump and one injection valve to perform automatic preconcentration-elution. A detection limit of 2. 9μg/L and an enhancement factor of 32 were achieved with a 40 s loacling perlod. The relative standard deviations were 1. 0% and 1.4% for the 200 μg/L Pb and 40 μg/L Pb respectively. Interferences from common diverse ions such as 1 mg/L Cu2+ and 50 mg/L Fe3+ were removed by addition of 0. 5% aseorbic acid, 0. 1 % o-phenanthroline and 1 % thiourea into the test solution. The developed method has been applied to the determination of trace lead in various water samples.更多还原