三乙酸甘油酯酸度的电动连续分液器快速滴定.pdfVIP

2015 年2 月 烟草科技 Feb. 2015 第48 卷第2 期 Tobacco Science Technology Vol. 48 No. 2 三乙酸甘油酯酸度的电动连续分液器快速滴定 边照阳，刘珊珊，杨 飞，李中皓，张洪非，唐纲岭* 国家烟草质量监督检验中心，郑州高新技术产业开发区枫杨街2 号 450001 摘要：为提高烟用三乙酸甘油酯酸度的检测效率，建立了一种三乙酸甘油酯酸度的快速滴定方 法，并采用该方法测定了10 个国内外烟用三乙酸甘油酯样品的酸度。结果表明：①优化确定 的滴定条件为：烟用三乙酸甘油酯样品用无水乙醇稀释并加入酚酞指示剂后，用电动连续分液 器快速添加0.02 mol/L NaOH 溶液，每次添加0.11 mL ，至显粉红色时记录加液次数，由三乙酸 甘油酯酸度值与NaOH 加液次数的对照表直接读出酸度值。②该方法的回收率为99.3%~ 99.6% ，相对标准偏差（RSD ）小于7% 。③所测的10 个样品中，有7 个样品的酸度检测结果小于 0.010% ，在限量值以内；有3 个样品的酸度检测结果大于0.010% ，超过限量值，其中2 个样品的 酸度大于0.020%。该方法操作简便快速、数据准确，适合用于三乙酸甘油酯样品的酸度测定。 关键词：滤棒；三乙酸甘油酯；酸度；滴定；电动连续分液器 中图分类号：TS426 文献标志码：A 文章编号：1002-0861（2015 ）02-0043-04 DOI: 10.16135/j.issn 1002-0861 RapidTitrationofTriacetinAcidityUsingElectricContinuousLiquidDivider BIAN Zhaoyang, LIU Shanshan, YANG Fei, LI Zhonghao, ZHANG Hongfei, and TANG Gangling* China National Tobacco Quality Supervision Test Center, Zhengzhou 450001, China Abstract: In order to determine the acidity of triacetin efficiently, a rapid titration method was developed with electric continuous liquid divider, and the acidity of 10 domestic and imported triacetin samples was determined. The results showed that: 1) The optimized procedure was as follows: triacetin sample was diluted by anhydrous ethanol, phenolphthalein was added as an indicator, then 0.11 mL of 0.02 mol/L NaOH solution was added quickly by an electric continuous liquid divider at the rate of 0.11 mL every dose repeatedly until solution ’s color turned pink, the total dose number of NaOH solution addition could be directly translated into triacetin acidity by a conversion table. 2) The recoveries of the method ranged from 99.3% to 99.6% with the relative standard deviations (RSDs) less