β-环糊精存在下氯化铁褪色光度法测定微量氟  

Fading spectrophotometric determination of trace fluorine with ferric chloride in the presence of β-cyclodextrin

作　　者：李咏梅[1,2] 李人宇[2,3] 付培楠[1] 张龙[1] 

机构地区：[1]淮海工学院化学工程学院,江苏连云港222005 [2]淮海工学院江苏省海洋资源开发研究院,江苏连云港222005 [3]连云港师范高等专科学校,江苏连云港222006

出　　处：《冶金分析》2010年第3期50-52,共3页Metallurgical Analysis

基　　金：连云港市科技项目(SH0816);江苏省海洋资源开发研究院科技开放基金项目(JSIMR09C08)资助

摘　　要：β-环糊精存在下，在PH1．6的KCl-HCl缓冲溶液中，F^-与FeCl3反应生成白色结晶性络盐使溶液褪色，据此建立了褪色光度法测定氟的新方法。络合物的最大褪色波长为263nm，体系的褪色程度与F^-浓度在0～10．0mg／L范围内呈线性关系，检出限为47．9μg／L。大量金属离子的干扰采用蒸馏法分离或8-羟基喹啉沉淀法去除；MnO4^-、Cr2O7^2-和VO3^-的干扰用抗坏血酸掩蔽。方法用于测定磷矿和药厂工序废水中氟时，PO4^3-和Ca^2＋的干扰用蒸馏法分离去除，相对标准偏差小于2．3％（n=5），平均回收率为98％～102％。A new fading spectrophotometric method was developed for the determination of fluorine. The method is based on the reaction between F^- and FeCl3 in KCl-HCl buffer solution at pH 1-6 in the presence of β-cyclodextrin, which forms white crystalline complex salt, resulting in fading of the solution. The maximum fading wavelength located at 263 nm. The systerm＇s fading degree was linear with the concentration of F^- in the range of 0-10. 0 mg/I. The detection limit was 47. 9μg/L. Many metal ions could be separated by distillation or precipitation with 8- hydroxyquinoline. Interfering ions of MnO4 , Cr2O7^2- and VO3 could be masked by ascorbic acid. The method was applied to determine fluorine in phosphorus ore sample and wastewater sample of working procedure from pharmaceutical factory, and the interfering ions of PO4^3- and Ca^2＋ were separated by distillation. The relative standard deviation was no larger than 2. 3 % （n = 5）, and the average recovery was in the range of 98%-102%.

关 键 词：褪色光度法 氟 氯化铁 Β-环糊精 磷矿 工序废水 

分 类 号：O613.41[理学—无机化学]