Chemistry of inorganic uranium compounds in liquid ammonia

• Applicant: Professor Dr. Florian Kraus
• Subject Area: Solid State and Surface Chemistry, Material Synthesis
• Term: since 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 437420997

In the present application, reactions of uranium compounds in ammonia are to be investigated exploratively. We have established the approaches for the previously known binary uranium halides, so that we now want to prepare both known and, if possible, previously unknown ternary uranium halides, for example those of alkali metals and alkaline earth metals, in order to investigate their reactions with ammonia. Furthermore, reducing and oxidizing agents for anhydrous ammonia are to be established that allow the oxidation and reduction of U-compounds. Ag(I) and Au(I) compounds and metals soluble in ammonia at normal pressure will be used for this purpose. Alkali metal amides, which lead to the ammonobasic pH range in ammonia, and ammonium compounds, which open up the ammonoacidic pH range, will be used to investigate the ammonolysis reactions of U compounds in detail and characterize the resulting products. An attempt will be made to prepare pseudobinary uranium pseudohalides, e.g. U(CN)4 or U(SCN)4. Uranyl(V) compounds, i.e. those with the species UO2_+, appear to be significantly more stable in NH3 than in aqueous solution. Targeted approaches to UO2_+ compounds are to be explored.

• DFG Programme: Research Grants