摘要
用碘量法测定复杂含硒物料中常量硒并对测定条件做试验。试样经硝酸及硫酸溶解、蒸发至冒烟后,盐类溶于盐酸中。在酒石酸存在下加盐酸羟胺,于70℃保温1h,放置1.5h使硒还原为单质硒并陈化。过滤,将单质硒溶于盐酸中,溶解温度为90℃,溶解时间为5min,滴定时溶液酸度宜在0.2~0.5mol·L-1(盐酸介质)。滴定时采用分步滴加碘化钾溶液,随即用硫代硫酸钠标准溶液滴定至淀粉指示剂所显蓝色消失,至再次加入碘化钾无蓝色出现为终点。按所耗硫代硫酸钠标准溶液的体积计算试样的含硒量。
Iodometry was applied to the determination of major amount of selenium in complex Se-bearing materials and optimum conditions for the determination were studied.The sample was dissolved in HNO3and fumed with H2SO4.The salts were dissolved in HCl.Selenium ion in the solution was reduced to elementary state by hydroxylamine hydrochloride in the presence of tartaric acid at 70℃for 1hand aged for 1.5h.After filtering,the elementary selenium was dissolved with HCl at 90 ℃ for 5 min.Suitable acidity of the solution for iodometric titration was found between 0.2-0.5mol·L-1(in HCl).The mode of stepwise-addition of KI solution was adopted and titration with Na2S2O3standard solution was carried out after each addition of KI solution until no blue color of the starch indicator appeared.Content of Se in the sample was calculated from the volume of Na2S2O3 standard solution consumed.
出处
《理化检验（化学分册）》
CAS
CSCD
北大核心
2014年第4期458-461,共4页
Physical Testing and Chemical Analysis(Part B:Chemical Analysis)
关键词
碘量法
硒
复杂含硒物料
Iodometry
Selenium
Complex Se-bearing materials
