Solution Chemistry of Molten Amide-Nitrate Eutectics

aE. I. EWEKA and bD. H. KERRIDGE

aDepartment of Chemistry, University of Southampton, Highfield,
Southampton, SO17 1BJ United Kingdom


bDepartment of Engineering Materials, University of Southampton,
Highfield, Southampton, SO17 1BJ United Kingdom



Received 18 February 1998


The partial binary phase diagram, eutectic composition, and temperature were determined for butyramide-sodium nitrate and acetamide-lithium iodide; together with the densities of the eutectics from their melting points to 100 °C.

The reactions of seven first-row transition metal compounds were examined in acetamide-potassium nitrate eutectic and four in butyramide-sodium nitrate eutectic. Cobalt(II) chloride was highly soluble at 90 °C and 140 °C, respectively, giving electronic spectra typical of octahedral coordination. In the acetamide eutectic increasing the temperature, up to 140 °C, gave more tetrahedral coordination.

Chromium(III) chloride, nickel(II) chloride, and copper(II) sulfate gave solution spectra indicating octahedral coordination by amide and nitrate, while the probably tetrahedral chloro complexes formed by iron(III) chloride were rapidly solvolyzed. Potassium chromate and potassium dichromate were only very slightly soluble, initially forming yellowish/pale orange solutions, due to the chromium(VI) charge-transfer transition, but with some reduction to chromium(III).



Full paper in: Chem. Papers 53 (1) 11-15 (1999)