光度法快速测定食盐中的碘含量  

Photometric Method Quick Determination of Iodine in Table Salts

作　　者：汤家华 程乐华[1,2] TANG Jia-hua;CHENG Le-hua(School of Chemical and Material Engineering,Chaohu College,Chaohu 238000,China;Institute of Coordination Chemistry,Chaohu College,Chaohu 238000,China)

机构地区：[1]巢湖学院化学与材料工程学院,安徽巢湖238000 [2]巢湖学院配位化学研究所,安徽巢湖238000

出　　处：《安徽化工》2022年第5期107-109,共3页Anhui Chemical Industry

基　　金：巢湖学院配位化学研究所资助。

摘　　要：研究了在磷酸介质中,碘化钾被碘酸钾氧化成单质碘,单质碘与过量的碘化钾反应生成I_(3)^(-),I_(3)^(-)与可溶性淀粉发生反应生成一种蓝色配合物,且显色的程度与IO_(3)^(-)的量成正比,据此建立了光度法测定食盐中碘含量的分析方法。配合物的最大吸收波长为585 nm,碘的含量在0~70μg/25 mL的范围内服从比耳定律,表观摩尔吸光系数为9.68×10^(4)L·mol^(-1)·cm^(-1)。方法的应用范围广,选择性好,灵敏度高,分析成本低,方便快捷,应用于食盐中碘含量测定时,得到了满意的结果。In the phosphoric acid medium,potassium iodide is oxidized into molecular iodine by potassium iodide,molecular iodine and excess potassium iodide reaction to produce I_(3)^(-),I_(3)^(-)reacts with soluble starch to form a blue complex,and the chromomeric extent was linear with the content of IO_(3)^(-),a new photometric method for the determination of iodine was developed.The maximum absorption wavelength of the complex was 585 nm,Beer′s law was obeyed for the mass concentration of the iodine in range of 0~70μg/25 mL.The apparent molar absorption coefficient was 9.68×10^(4)L·mol^(-1)·cm^(-1)。The method has a wide range of applications,good selectivity,high sensitivity,low cost,convenience and rapidness.It had been applied to the determination of iodine in table salts with satisfactorty ressults.

关 键 词：光度法 快速测定 碘 食盐 

分 类 号：O657.3[理学—分析化学] TS37[理学—化学]