流动分析-离子选择电极法测定水中痕量氟化物  

Determination of Trace Fluoride in Water with Flow Analysis-Ion Selective Electrode

作　　者：赵立晶[1] 赵萍[1] 魏月仙[1] 

机构地区：[1]北京吉天仪器有限公司,北京100015

出　　处：《分析化学》2011年第10期1526-1530,共5页Chinese Journal of Analytical Chemistry

摘　　要：基于流动分析-离子选择电极技术,建立了一种测定水中痕量氟化物的分析方法。体系使用注射泵将注入的样品推出,在稳态的条件下进行测定。样品与总离子强度缓冲溶液(TISAB)等体积混合后,采用蠕动泵注入样品,注入量为400"L。采用注射泵驱动载流速度快,比蠕动泵效果好。载流为0.05mg/L F-标准溶液,采用奥立龙(Orion)电极,倾斜20°的喷壁型(Wall-jet)流通池。样品之间插入清洗,方法没有交叉携出。在最佳的条件下,方法的线性范围为0.05～1.0mg/L,检出限为0.015mg/L,RSD为1.5%(0.2mg/L)。样品分析频率为30样/h。本方法对质控样品的测定结果令人满意。3个水样的加标回收率为96.8%～104.5%。用4个水样与国标中的手工分析方法进行了对比,在95%的置信区间内,配对t检验结果无显著差异。本方法灵敏度高,分析速度快、试剂消耗少,废液排放量低,适用于水中低浓度样品的分析。An analytical method based on flow analysis-ion selective electrode was established to measure the content of trace fluoride in water.The sample was propelled by the syringe pump and the determination was carried out at steady state.The sample was mixed with the total ionic strength adjustment buffer（TISAB） of the ratio 1∶1 and injected by the peristaltic pump.The volume of injection sample was 400μL.The rate of the carrier propelled by the syringe pump is faster than by the peristaltic pump.Experimental parameters including the concentration of fluoride in carrier,the volume of injection sample,carryover and interference were studied.The carrier was fluoride standard solution with the concentration was 0.05 mg/L and the Orion electrode and the wall-jet flow cell with an angle of 20° were used.The cleaning procedure was used between different samples and nocarryover was observed.The interference was studied.Under the optimized experimental condition,the linearity and the detection limit of the proposed method were found to be 0.05-1 mg/L and 0.015 mg/L.The relative standard deviation of 0.2 mg/L sample were 1.5%（n=7）.The throughout was 30 h-1.The certified reference material was tested with satisfactory result.Three samples were analyzed with the recovery 96.8%-104.5%.Using the paired Student′s t-test at the 95% confidence level,the results of the proposed method and the batch method based on GB/T 5750.5-2006 for determination of the seven samples showed no significant difference.The proposed method allows the determination of fluoride in water samples at trace levels with high sensitivity,high throughout,reduced reagent consumption and low waste production.

关 键 词：流动分析 离子选择电极 氟化物 

分 类 号：X832[环境科学与工程—环境工程] O657.1[理学—分析化学]