利用不稳定Konig体系的中间产物光度法快速测定水中氰化物  

Rapid Determination of Cyanide in Water by Spectrophotometry with Intermediate Product of Unstable Konig System

作　　者：李晓惠[1] 刘海军[1] 许艳广[1] LI Xiao-hui;LIU Hai-jun;XU Yan-guang(Department of Biomedical and Chemical Engineering,Liaoning Institute of Science and Technology,Benxi 117004,China)

机构地区：[1]辽宁科技学院药化学院,辽宁本溪117004

出　　处：《化学试剂》2022年第6期915-919,共5页Chemical Reagents

基　　金：辽宁省教育厅服务地方项目(L2020lkyfwdf-06);辽宁省教育厅面上项目(LJKZ1064)。

摘　　要：以异烟酸、双甲酮分别作为Konig反应的开环、缩合试剂,产生的聚甲炔染料在该异烟酸-双甲酮体系中易分解,该体系为不稳定的Konig体系,但其中间产物具有较高的摩尔吸收系数(ε),采用分光光度法获得其中间产物的A~t曲线,相应建立了快速测定氰化物的新方法。在拟定的实验条件下,该体系的中间产物在531 nm处产生最大吸收,ε为2.36×10^(4) L/(mol·cm),其A~t曲线呈近似平顶峰型,氰化物浓度在0.010~0.800 mg/L范围内与A~t曲线中的A_(max)呈良好的线性关系(R=0.9998),单个样品的测试时间小于5 min。该方法用于焦化废水中氰化物的测定,回收率在97.9%~101.1%之间,RSD≤1.5%,其测定值与标准方法的测定值吻合,该研究为将Konig反应拓展应用至不稳定体系提供技术参考。In this study,isonicotinic acid and dimedone were used as the ring-opening reagent and condensation reagent of the Konig reaction,respectively.The in situ produced polymethine dye was easily decomposed in the isonicotinic acid-dimedone system which can be determined as an unstable Konig system.However,the intermediate product had a higher molar absorption coefficient(ε),the A~t curve of the intermediate product was obtained by using a new method based on spectrophotometry for the rapid determination of cyanide.In the given experimental condition,the intermediate product of the system has a_(max)imum absorption at 531 nm,featuring anεof 2.36×10^(4) L/(mol·cm).The A~t curve is approximately flat-top peak shaped,the cyanide concentration is in a good linear relationship with the A_(max)of A~t curve(R=0.9998)within the range of 0.010~0.800 mg/L,the testing time of a single sample is less than 5 min.The recovery of our method was 97.9%~101.1%and the RSD was less than 1.5%when applied to determine the cyanide in coking wastewater,the measured values were in good agreement with that of the standard method.Our study provides technical references for extending the application of the Konig reaction to unstable systems.

关 键 词：不稳定Konig体系 双甲酮 中间产物 分光光度法 氰化物 测定 

分 类 号：O657.32[理学—分析化学] X832[理学—化学]