流动注射在线富集原子吸收法测定痕量铅镉

在含铅、镉的试液中加入pH=5.72乙酸-乙酸钠缓冲溶液3.20 mL,泵的转速恒为5 mL/min,用自制的强酸性阳离子交换树脂柱对试液中的铅、镉在线富集150 s,1.50 mol/L HNO3溶液洗脱20 s,火焰原子吸收法测定铅、镉的含量。该方法的线性范围分别是0~80.0μg/L、0~40.0μg/L,检出限分别为3.0μg/L、1.0μg/L,富集倍数分别为40倍、35倍。用该方法测定地表水中铅、镉的含量,结果满意。

Application of Online Preconcentration Flow Injection in the Determination of Trace Lead and Cadmium by Flame Atomic Absorption Spectrometry

Lead and cadmium were enriched using strong acid cation exchange resin with 3.20 mL of acetic acid-sodium acetate buffer solution(pH 5.72) and rotate speed of pump 5 mL/min.Lead and cadmium were eluted using 1.50 mol/L HNO3 for 20 s and the content of them were measured using flame atomic absorption spectrometry.The linear ranges of lead and cadmium were 0~80.0 and 0~40.0 μg/L,respectively.The detection limits of them were 3.0 and 1.0 μg/L,respectively.The enrichment factors were 40 and 35,respectively.The method was used to measure the content of lead and cadmium in surface water and satisfactory results were obtained.