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...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–1 with a correlation coefficient of R2=0.9999 (n=7). The experimental detection limit is 0.05mgL–1. The sampling frequency is 15 samples h–1 and the relative standard deviation was 2.1% for 0.05 mg?L–1. 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.展开更多
In current spent nuclear fuel reprocessing,the predominant method involves chemical extraction,leveraging the differing distribution ratios of elements to achieve separation and purification.Effective separation of ur...In current spent nuclear fuel reprocessing,the predominant method involves chemical extraction,leveraging the differing distribution ratios of elements to achieve separation and purification.Effective separation of uranium(U),plutonium(Pu),and neptunium(Np) typically relies on redox processes that alter their oxidation states during extraction.Therefore,reductants play a critical role in reprocessing processes.An important shift in the advanced reprocessing process is the use of salt-free reagents in the actinide separation process.In addition,the salt content in the reprocessing stream is often indicative of the overall technological sophistication of the process,and it is critical to reform the reductants used in the main process stream.Salt-free reductants have attracted much attention in recent years for basic and applied research in reprocessing processes because of their advantages such as being easily destroyed,not introducing salts,reacting quickly,simplifying the process,and reducing the amount of waste.This study summarizes emerging salt-free reagents with potential applications in reprocessing,and outlines their kinetic and chemical reaction mechanism properties in reducing Pu(Ⅳ) and Np(Ⅵ).The conclusion discusses the future potential of salt-free reagents in reprocessing.This study summarizes the currently well-studied salt-free reductants and offers recommendations and future research directions in salt-free alternatives.展开更多
文摘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–1 with a correlation coefficient of R2=0.9999 (n=7). The experimental detection limit is 0.05mgL–1. The sampling frequency is 15 samples h–1 and the relative standard deviation was 2.1% for 0.05 mg?L–1. 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.
文摘In current spent nuclear fuel reprocessing,the predominant method involves chemical extraction,leveraging the differing distribution ratios of elements to achieve separation and purification.Effective separation of uranium(U),plutonium(Pu),and neptunium(Np) typically relies on redox processes that alter their oxidation states during extraction.Therefore,reductants play a critical role in reprocessing processes.An important shift in the advanced reprocessing process is the use of salt-free reagents in the actinide separation process.In addition,the salt content in the reprocessing stream is often indicative of the overall technological sophistication of the process,and it is critical to reform the reductants used in the main process stream.Salt-free reductants have attracted much attention in recent years for basic and applied research in reprocessing processes because of their advantages such as being easily destroyed,not introducing salts,reacting quickly,simplifying the process,and reducing the amount of waste.This study summarizes emerging salt-free reagents with potential applications in reprocessing,and outlines their kinetic and chemical reaction mechanism properties in reducing Pu(Ⅳ) and Np(Ⅵ).The conclusion discusses the future potential of salt-free reagents in reprocessing.This study summarizes the currently well-studied salt-free reductants and offers recommendations and future research directions in salt-free alternatives.
