锡砷冶金物料中硝酸盐的直接电极电位法研究

采用离子选择性电极分析技术,在硫酸铝-硫酸银-硼酸-氨基磺酸离子强度剂体系中对锡酸钠、砷酸液等两种物料中的硝酸盐进行检测。用稀酸碱沉淀分离不大于0.80g锡酸根或25mg铁、锑、钙,200mg砷不产生干扰,硝酸盐浓度在3.23×10-5mol/L～1.61×10-2mol/L内电极响应符合能斯特方程式（斜率≥90%）,检测下限可达1.61×10-5mol/L,相对标准偏差（m=6,n=5～11）为1.44%～9.64%,加标回收率为86.0%～123.4%。

Direct Electrode Potentiometry Determination Investigation for Nitrate in Metallurgical Material of Tin-Arsenic

For purpose of developing new analysis for nitrate on tin-arsenic metallurgical material,a ion selective electrode method for the determination of NO3 in sodium stannate and arsenic acid liquid was established.It was found that effect of ≤0.80g stannate or 25mg Fe,Sb,Ca was disappeared by dilute acid or alkali and 200mg As did not interfere in detecting.Eectrode response coincided with Nernst equation when concentration of NO3 was in range of 3.23×10-5mol/L～1.61×10-2mol/L(Slope≥90%).Detection limit was found to be 1.61×10-5mol/L.Tests for precision and recovery at different concentration levels were made,giving values of RSD’s(m=6,n=5-11)and of recovery in ranges of 1.44%-9.64% and 86.0%-123.4% respectively.