流动注射光度法测定水样中的肼

On-line determination of hydrazine in environmental water by flow injection analysis

利用肼类化合物在酸性介质中与香草醛反应形成黄色腙类化合物,在波长410nm处具有最大的光度吸收,建立了流动注射分析(FIA)技术与分光光度法联用直接测定环境水样中的微量肼的在线分析方法。结果表明,在最佳检测条件下,肼在2～1500μg/L范围内有良好的线性关系,相关系数R2=0.9998,检测限为0.7μg/L,每小时进样20次,100μg/L的肼样品相对标准偏差(RSD)为0.92%(n=11)。利用该方法分析河水、井水、池塘水、污水中的肼,回收率为97.3%～106.1%,结果与国家标准法一致。

A simple,accurate,sensitive and selective flow injection spectrophotometric method for rapid determination of hydrazine was proposed in this paper,which was based on the condensation reaction of hydrazine with 3-methoxy-4-hydroxybenzaldehyde to form hydrazone.The resulting yellow colored product is stable in an acidic medium and has a maximum absorption at 410 nm.Under the optimal conditions,the absorption intensity linearly increased with the concentration of hydrazine in the range from 2 to 1500 μg/L with a correlation coefficient of R2=0.9998 and the detection limit of 0.7 μg/L.The sampling frequency was 20 samples per hour and the relative standard deviation was 0.92%（n=11）for 100μg/L.This proposed method was suitable for automatic and continuous analysis,and successfully applied to the determination of the content of hydrazine in river water,pond water,well water and waste water samples with the recoveries of 97.3%～106.1%.