水蒸气蒸馏分离-电位滴定法测定烟草中总挥发酸  

Potentiotitrimetric Determination of Total Volatile Acids in Tobacco with Separation by Steam Distillation

作　　者：耿永勤 缪恩铭 蒋次清 徐济仓[1] 杨叶昆[1] 李雪梅[1] 

机构地区：[1]云南省烟草化学重点实验室,云南烟草科学研究院,昆明650106

出　　处：《理化检验（化学分册）》2011年第10期1206-1207,1210,共3页Physical Testing and Chemical Analysis(Part B:Chemical Analysis)

摘　　要：采用水蒸气蒸馏法分离烟草中挥发酸,电位滴定法测定了其中总挥发酸的含量。以氢氧化钠标准溶液为滴定液,通过加入三氟乙酸进行电位滴定做回收试验,测得回收率在98%～103%之间,对3个样品按试验方法试验后做精密度试验,测得相对标准偏差(n=7)在1.0%～1.1%之间。两者的结果均优于常规的手工滴定法。The volatile acids in tobacco were separated by steam distillation, and content of total volatile acids in the distillate was determined by potentiometric titration. Standard sodium hydroxide solution was used as titrant. Test of accuracy was made by the addition of trifluoro acetic acid, giving values of recovery in the ranges of 98%- 103% .Precision was tested by analyzing 3 tobacco samples, giving values of RSD＇s （n=7） in the range of 1.0% It was found that accuracy and precision obtained by the present method were better than that of the conventional manual titration method.

关 键 词：电位滴定法 水蒸气蒸馏 烟草 总挥发酸 

分 类 号：O657.15[理学—分析化学]