摘要
在稀盐酸介质中，微量镧（Ⅲ）对溴酸钾氧化甲基红褪色反应有明显阻抑作用，据此建立了阻抑动力学光度法测定微量镧（Ⅲ）的新方法。讨论了酸度、反应温度、时间、试剂用量及共存离子的影响，确定了实验最佳反应条件，并测定了阻抑反应的表观速率常数和表观活化能。方法线性范围为0．01～0．4mg／L，检出限为2．21×10^-6g／L。用于合成样品及镧汞齐中镧的测定，相对标准偏差为2．56％～4．18％（n=6），回收率为97．0％～102．0％。
On the basis of inhibiting effect of micro lanthanum（Ⅲ） on the discoloring reaction of methyl red with potassium bromate in the dilute hydrochloric acid medium, a new kinetic spectrophotometric method for the determination of micro lanthanum（Ⅲ） has been developed. The factors such as acidity, concentration of reagents, reaction time and temperature, influence of coexisting ions were discussed, the optimum reac-tion conditions were established. The apparent rate constant and apparent activation energy of the reaction are also were determined. The linear range is 0.01 - 0.4 mg/L and detection limit is 2.21 ×10^-6 g/L.This method has been used for determination of lanthanum（Ⅲ） in synthetical samples and lanthanum amalgam, with RSD of 2.56% - 4.18% （n =6） and recovery of 97.0% - 102.0%.
出处
《冶金分析》
CAS
CSCD
北大核心
2006年第4期69-71,共3页
Metallurgical Analysis
基金
山东省教育厅高等学校2005年实验技术研究项目(鲁教备字2005-2)
关键词
镧
甲基红
溴酸钾
动力学光度法
lanthanum
methyl red
potassium bromate
kinetic spectrophotometry
