Oxidative Dissolution of Neptunium(iv) Oxide in Carbonate Solutions

Abstract

This article presents preliminary results of the study of neptunium(IV) oxide dissolution in aqueous solutions of Na2CO3 in the presence of ammonium persulfate and hydrogen peroxide. In these carbonate systems, the value of NpO2 dissolution yield did not exceed 1.5-1.6%. Ultrasonication makes it possible to significantly increase the dissolution rate of neptunium(IV) oxide in Na2CO3 solutions in the presence of hydrogen peroxide. Under such conditions, about 25% of neptunium(IV) oxide powder can be dissolved in one dissolution step (210-270 min). A possible factor affecting the increase of NpO2 dissolution yield is the increase of oxidative and reaction activity in the carbonate systems under ultrasonic impact.