Neptunium(IV) oxalate

Template:Chembox Neptunium (IV) oxalate is an inorganic compound, a salt of neptunium and oxalic acid with the chemical formula Np(CTemplate:SubOTemplate:Sub)Template:Sub. The compound is slightly soluble in water, forms crystalline hydrates—green crystals.

Synthesis

Neptunium(IV) oxalate is formed by the oxalic acid precipitation of neptunium (IV) solutions:

$𝖭𝗉𝖢{𝗅}_{\mathrm{𝟦}}\mathsf{+}\mathrm{𝟤}{𝖧}_{\mathrm{𝟤}}{𝖢}_{\mathrm{𝟤}}{𝖮}_{\mathrm{𝟦}}\stackrel{}{\to }𝖭𝗉\mathsf{(}{𝖢}_{\mathrm{𝟤}}{𝖮}_{\mathrm{𝟦}}{\mathsf{)}}_{\mathrm{𝟤}}\mathsf{\cdot }\mathrm{𝟨}{𝖧}_{\mathrm{𝟤}}𝖮\mathsf{\downarrow }\mathsf{+}\mathrm{𝟦}𝖧𝖢𝗅$

Physical properties

Neptunium(IV) oxalate forms a crystalline hydrate of the composition Np(C₂O₄)₂ • 6H₂O with green crystals.

It is insoluble in acetone, and slightly soluble in water.

Chemical properties

Neptunium(IV) oxalate decomposes on heating:

$𝖭𝗉\mathsf{(}{𝖢}_{\mathrm{𝟤}}{𝖮}_{\mathrm{𝟦}}{\mathsf{)}}_{\mathrm{𝟤}}\stackrel{400^{o}C}{\to }𝖭𝗉{𝖮}_{\mathrm{𝟤}}\mathsf{+}\mathrm{𝟤}𝖢{𝖮}_{\mathrm{𝟤}}\mathsf{+}\mathrm{𝟤}𝖢𝖮$

Applications

Neptunium(IV) oxalate is used as an intermediate product in the purification of neptunium.