两性和非离子混合表面活性剂存在下铀-铬天菁S体系分光光度法研究

本文研究了铀-铬天菁S-混合表面活性剂多元络合物的形成条件,初步探讨了两性-非离子混合表面活性剂的协同作用。本文采用CyDTA-酒石酸混合掩蔽剂,直接测定了以高钍、高稀土、高锆为主的矿石中的微量铀,结果令人满意。

SPECTROPHOTOMETRIC STUDY ON THE SYSTEM OF URANIUM-CHROMAZUROL S IN THE PRESENCE OF AMPHOTERIC-NONIONIC MIXED SURFACTANT

A simple, selective and highly sensitive procedure for spectropho-tometric determination of uranium has been developed. In pH 6.0-8.5, uranium reacts with chromazurol Sand amphoteric-nonionic mixed surfactant to form a blue complex, which has absorption maxima at 615 nm. The molar absorptivity at 615 nm is 1.1-1.2×10⁵. The composition of the complex is established as U: CAS = 1:1 by the methed of job and the equilibrium shift. Beer's law is obeyed for 0-50 μg/25 ml of uranium. The complex is very steady,that could allow the presence of masking agents in a great amounts. Thus, a great majority of metal ions do not disturb the determination of uranium.In this paper, the formation conditions of the complex was studied, it was also researched to enchance sensitization mechamism using mixed surfactant. In this work CyDTA-Tar mixed masking agent was adopted and a minute amount of uranium in ores containing high-thorium, high-rare earths and high-zirconium, respectively, has been determined without separation.