离子缓冲剂对选择性电极法测定湿法炼锌体系中氟的影响

摘要

The influence of total ionic strength adjustment buffer addition on the determination of F -in sol-ubility phase diagram of zinc hydrometallurgy system by fluorine ion selective electrode-standard curve method and standard addition method was systemically investigated.The research results showed that:(1) as a whole,the measurement results of fluorine ion selective electrode-standard addition method were much better than those obtained by standard curve method regardless of addition amount of total ionic strength adjustment buffer;(2)in fluorine ion selective electrode-standard addition method,the determi-nation results were greatly affected by the addition amount of total ionic strength adjustment buffer;(3) when the background ion concentration in testing solution was very low,the addition of total ionic strength adjustment buffer had negative effect on the accuracy of analytical results.In other words,the results were better without addition of total ionic strength adjustment buffer;(4)when the background ion concentra-tion in testing solution was relatively high,the addition of total ionic strength adjustment buffer was ad-vantageous the improvement of determination precision.The experimental results were applied for the de-termination of F -in solution of zinc hydrometallurgy.The lowest error was 0.93%.%试验系统地研究了离子缓冲剂的加入在氟离子选择性电极-标准曲线法和标准加入法测定湿法炼锌体系溶解度相图中F-时的影响规律.研究结果表明:(1)不论离子缓冲剂的加入量,整体来说,氟离子选择性电极-标准加入法的测量结果远优于标准曲线法;(2)在氟离子选择性电极-标准加入法中,离子缓冲剂加入量会对测定结果产生严重影响;(3)当待测溶液中背景离子浓度很低时,离子缓冲剂的加入对分析结果准确性有负面影响,即不加离子缓冲剂的结果更好;(4)在待测溶液中背景离子浓度较高时,离子缓冲剂的加入有利于提高测定结果的精度.实验结果应用于湿法炼锌液中F -的测定,最低误差为0.93%.