食盐中碘含量的自动电位滴定法测定研究

Automatic potentiometric titration study of the iodine content in salt

目的建立快速、简便、准确的食盐中碘含量的自动电位滴定检测方法。方法用瑞士万通Metrohm809 Titrando自动电位滴定仪测定食盐中的碘含量。结果不同样品中的加标回收率为97.4%～99.0%,相对标准偏差为0.81%～1.37%(n=6),对10份样品分别用自动电位滴定法和直接滴定法测定,两种方法所得结果无显著性差异(P>0.05)。结论自动电位滴定法操作简单、快速,自动化程度高,测定食盐中碘含量时准确度高,重现性好,适合作为盐碘测定的常规分析方法。

Objective Establish a fast,easy,accurate iodine in salt content by automatic potentiometric detection method.Methods Determination of iodine content in salt use the Metrohm809 Titrando automatic potentiometric titrator.Results The recovery rate in the different samples was 97.4%~99.0%,relative standard deviation was 0.81%~1.37%（n=6）.It was shown that there was no significant difference between automatic potentiometric titration and direct titration by applying 10 samples（P0.05）.Conclusion Automatic potentiometric titration method was simple,rapid and high degree of automation,the determination of iodine content in salt,high accuracy,good reproducibility,conventionally analytical methods for the determination of salt iodine.