Study on Effects of Process Variables on the Yield of Ammonium Uranyl Carbonate Precipitation from Uranyl Nitrate-Ammonium Carbonate Solutions

Sadeghi, M. H; Outokesh, M; Ghasemi, M. R; Zarean, A

Study on Effects of Process Variables on the Yield of Ammonium Uranyl Carbonate Precipitation from Uranyl Nitrate-Ammonium Carbonate Solutions

Document Type : Scientific Note

Authors

M. H Sadeghi

M Outokesh

M. R Ghasemi

A Zarean

Abstract

Ammonium uranyl carbonate (AUC), an intermediate material in the process of conversion of yellowcake to uranium hexafluoride, was produced by injection of an aqueous solution of ammonium carbonate (AC) into uranyl nitrate solution. The target parameter in optimization of this process was the yield of the precipitation, as morphology and size distribution of AUC play no role in its post processing to UF₆. The aim of the current study was the experimental investigation of the effects of the process variables on the yield of AUC precipitation. The results showed that the flow rate and flow pattern of the injection of the AC solution, aging time, impeller speed, and temperature had little effects on the yield of AUC precipitation. On the other hand, the yield was increased by increasing the ammonium carbonate to uranyl nitrate molar ratio, ammonium carbonate concentration, and uranyl nitrate concentration. However, it decreased by increasing the molar ratio of CO₃^2- to NH₄⁺ ions in the ammonium carbonate solution.

Highlights

مراجع

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Keywords

Ammonium Uranyl Carbonate

Ammonium Carbonate

Uranyl Nitrate

Yield of Precipitation

20.1001.1.17351871.1396.38.3.10.2