Studies on the uranium speciation in zinc iron phosphate (ZnIP) glass using Mossbauer and EXAFS spectroscopic investigations

5-15 mol % UO3 loaded zinc iron phosphate glass was prepared by melt quench process. The solubility of UO3 in ZnIP was determined by XRD and was found to be below 15 mol %; beyond which separation of UP2O7 compound was observed. Mo center dot ssbauer spectroscopy unraveled the ratio of Fe (II)/Fe(III) and was found to decrease from 0.071 (ZnIP) to 0.029. EXAFS studies unraveled the prevalence of two type of coordination for U-O (i.e U-O1 and UO2) and Fe-O (Fe-O1 and Fe-O2) in the ZnIP glass matrix, whereas a single chemical environment for Zn-O in the same glass matrix.

Automated summary

A zinc iron phosphate glass loaded with 5-15 mol% UO3 was prepared by melt quench process. The solubility of UO3 in ZnIP was determined to be below 15 mol%, with separation of UP2O7 compound observed beyond this concentration. Fe(II)/Fe(III) ratio was found to decrease from 0.071 to 0.029, and two types of coordination for U-O and Fe-O were prevalent in the ZnIP glass matrix, while a single chemical environment for Zn-O was observed.