Flow Injection Analysis of Hydrazine in the Aqueous Streams of Purex Process by Liquid Chromatography System Coupled with UV-Visible Detector

Present study describes the development of a rapid, sensitive and selective flow injection analysis of hydrazine in the aqueous streams of purex process by liquid chromatography system coupled with UV-Visible detector. The method is based on the formation of yellow coloured azine complex by reaction of hydrazine with para-dimethy laminobenzaldehyde (pDMAB). The formed yellow coloured complex is stable in acidic medium and has a maximum absorption at 460 nm. The presence of uranium in hydrazine solution is not interfering in the analysis. Under optimum condition, the absorption intensity linearly increased with the concentration of hydrazine in the range from 0.05 10 mg·L with a correlation coefficient of R = 0.9999 (n = 7). The experimental detection limit is 0.05 mg·L. The sampling frequency is 15 samples·h and the relative standard deviation was 2.1% for 0.05 mg·L. This method is suitable for automatic and continuous analysis and successfully applied to determine the concentration of hydrazine in the aqueous stream of nuclear fuel reprocessing.