电位滴定法测定硫酸铵中氮含量  

Determination of Nitrogen in Ammonium Sulfate by Potentiometric Titration

作　　者：刘月菊 宋明明 邸卫利 姜雪莲 丁琳 李茜 LIU Yueju;SONG Mingming;DI Weili;JIANG Xuelian;DING Lin;LI Qian(Dalian Bolong New Materials Co.,Ltd.,Dalian,Liaoning 116450,China)

机构地区：[1]大连博融新材料有限公司

出　　处：《中国无机分析化学》2019年第6期73-77,共5页Chinese Journal of Inorganic Analytical Chemistry

摘　　要：建立了一种酸碱电位滴定法直接测定硫酸铵中氮含量的方法。样品溶解后,可直接用氢氧化钠标准滴定溶液进行滴定。为了保证检测的准确度,分别使用硫酸铵高纯试剂和邻苯二甲酸氢钾基准试剂对氢氧化钠标准滴定溶液进行标定,并对标定结果进行比较,两种方法基本无差异。同时,通过适量硫酸的加入避免了样品中游离硫酸对检测结果的影响。结果表明,测得氮含量的加标回收率为99.9%~100%,相对标准偏差(RSD,n=5)为0.03%~0.05%。分别使用实验方法和蒸馏后滴定法测定不同样品的氮含量,结果相吻合。方法检测速度快、检测精度高、绿色环保、易于控制,非常适合于硫酸铵中氮含量的测定。将方法与蒸馏后滴定法(仲裁法)检测结果进行比较,两种方法无显著性差异。A method for the direct determination of nitrogen in ammonium sulfate by acid-base potentiometric titration was established.After the sample is dissolved,it can be directly titrated with sodium hydroxide standard titration solution.In order to ensure the accuracy of detection,the standard titration of sodium hydroxide was respectively calibrated with ammonium sulfate high purity reagent and potassium hydrogen phthalate reference reagent,and the calibration results were compared.There was no difference between the two methods.At the same time,the influence of free sulfuric acid on the test results was avoided by adding appropriate amount of sulfuric acid.This method has the advantages of high detection speed,high precision,environmental protection and easy control.There was no significant difference between the two methods when compared with the results of distillation titration(arbitration).The standard recovery of nitrogen content measured by this method is 99.9%—100%,and the relative standard deviation is 0.03%—0.05%.The nitrogen contents of different samples were determined by experimental method and titration after distillation,and the results were consistent.

关 键 词：电位滴定法 硫酸铵 游离硫酸 蒸馏后滴定法 

分 类 号：O655.2[理学—分析化学]