Ammonium diuranate

Yellow- reddish solid

Fixed

Insoluble in water and alkalis, soluble in acids

Risk

Template: Infobox chemical / molecular formula search available

Ammonium diuranate (ADU ) is a chemical compound containing nitrogen, hydrogen, oxygen, and uranium. It is created with the sodium diuranate in the production of yellowcake. Formally, ADU by the empirical formula ( NH4) 2U2O7 characterize. Indeed, various species of different composition are found, for which the general formula can be formulated [m UO3 · 2n · 2 NH3 (m -n) H2O ] · H2O p.

Production and representation

Diuranate is precipitated from uranyl sulfate solution by the addition of aqueous ammonia solution:

This reaction can be used in analytical chemistry as well as evidence of uranium (VI ) compounds.

Use

The diuranate obtained by the above reaction ( technically known as yellowcake ) is calcined, in order to extract Triuranium octoxide. This reaction proceeds via several intermediates; first part of the crystal water and ammonia is split off before the UO3 units are dehydrated and finally oxygen is eliminated. Formal is the overall equation:

The Triuranium octoxide is subsequently implemented in the process of producing uranium with nitric acid. This creates uranyl nitrate, can be isolated from the pure uranium trioxide. This is reduced with hydrogen to uranium dioxide. Bring to uranium dioxide with hydrofluoric acid and fluorine to the reaction, produced uranium hexafluoride, from which finally pure uranium is recovered by reduction with calcium or magnesium.