|用对二甲氨基苯甲醛分光光度法测定水中水合肼，将显色剂用量由5.0 mL降至3.0 mL，比色皿厚度由30 mm增至50 mm，水样酸度由1 mol/L降至0.5 mol/L，同时增加低浓度校准曲线，实现对其方法检出限的优化。结果表明，优化后方法检出限由0.007 8 mg/L降至0.001 0 mg/L，精密度及加标回收率均符合规范要求，能够保证低浓度水样的准确测定。
|关键词: 水合肼 对二甲氨基苯甲醛分光光度法 检出限
|Optimization of the Detection Limit of Hydrazine Hydrate in Water by Spectrophotometric Method
DING Jia, TENG Kai ling
Shaoxing Environmental Monitoring Center，Shaoxing, Zhejiang 312000，China
|The paradime thylaminobenzaldehyde spectrophotometric method was used for the determination of hydrazine hydrate in water and its detection limit was optimized. The dose of chromogenic agent was reduced from 5.0 mL to 3.0 mL, the thickness of cuvette was increased from 30 mm to 50 mm, the acidity of the water samples was reduced from 1 mol/L to 0.5 mol/L, and the amount of sampling points at low concentrations on the calibration curve was increased all of which were used to optimize the detection limit. The experimental results showed that the optimized detection limit decreased significantly from 0.007 8 mg/L to 0.001 0 mg/L. The precision and recovery rate could both meet the requirements of the specification, which guaranteed the accuracy of the determination of water samples at low concentration.
|Key words: Hydrazine hydrate Paradime thylaminobenzaldehyde spectrophotometric method Detection limit