石墨炉法测定强化营养盐中铅含量

Determination of lead in fortified nutrient salt by graphite furnace method

本文结合强化营养盐系列标准,探讨石墨炉原子吸收光谱法直接测定强化营养盐中铅的方法。方法用稀酸溶样,采用磷酸二氢铵作基体改进剂,直接上机测定铅含量。与标准方法比较,前处理方法简单,操作简便,比较适合检测机构批量样品检测;同时,该法可避免有毒有害化学试剂的使用,绿色环保;最重要的是,石墨炉法检测限低,能满足强化营养盐中微量铅的测定要求(标准中铅限量为小于2mg/kg)。经检验,该法与标准中指定的铅测定方法两两比较,无显著性差异(t<t0.05,P>0.05)。

In this paper,the method of direct determination of lead in fortified salt by graphite furnace atomic absorption spectrometry was discussed in this paper. Using the method of dilute acid digestion,using two ammonium hydrogen phosphate as matrix modifier for determination of lead content directly on the machine. With standard method,pretreatment method is simple,convenient operation,is suitable for detection mechanism in bulk sample testing; at the same time,the method can avoid the use of toxic and harmful chemical reagent,green environmental protection; is the most important,the graphite furnace method has low detection limit,can meet the enhanced nutrient trace lead in determination of requirements（ standard limit for lead to less than 2 mg / kg）. After testing,the method and the standard specified in the lead determination method two two comparison,no significant difference（ t 〈t0. 05,P 〈0. 05）.