氢化物发生原子吸收测定食盐制品和盐化产品中微量铅

Plumbane Generation-Atomic Absorption Spectrometric Determination of Trace Amounts of Lead in Salt and Salt Products

方法采用铁氰化钾将盐溶液中的Pb2+氧化为Pb4+,用NaBH4-Hcl将Pb4+还原为铅烷(PbH4↑),进行原子吸收光谱测定.称样1.00g±0.02g于25ml比色管中,加无离子水约10ml溶解,加0.5mlHcl(4.2mol/l),0.5ml草酸(10g/l),1.0ml铁氰化钾(100g/l),用水定容至刻度,混匀后AAs测定,直读含量.方法检出限为0.012mg/kg,测定范围0～0.6mg/kg,相关系数为0.999X,回收率为95.6%～110%,平均为102%.RSD≤5.4%.方法简单易行,灵敏、快速、准确、环保、健康、更具人性化,特别适合食盐制品中微量铅的分析.

A method of hydride generation - atomic absorption spectrometry for the determination of trace amounts of lead in salt and salt products was described. Plumbane was generated in a reaction system of HCl -K3Fe（CN）6 -KBH4 using a continuous flow injection hydride generator. The generated plumbane was atomized with a quartz tube atomizer and measured with an atomic absorption spectrometer. Weigh 1.00g±0.02g salt staple in 25ml tube, dissolve it in about 10ml deionized water,add 0.5ml hydrochloric acid （4.2mol/l） ,0.5ml oxalic acid （10g/l） ,and 1.0ml potassium ferricy anide （100g/l）, add deionized water to make 25 ml, shake the tube thoroughly, measured with an atomic absorption spectromenter. The content of lead was directly read out. Detection limit of this method was 0.012mg/kg, Linearity was kept in rang of 0-0.6mg/kg with a correlation coefficient of 0. 999x. Recovery was kept in range of 95.6%-110% and average was 102% ,and RSD was better than 5.4%. This method is easier, convenient, sensitive,rapid, accurate, no pollution, healthy, more humanization and extremely suitable for the determination of trace amounts of lead in salt and salt chemical products.