Co-reduction of mixed oxides

Co-reduction of mixed oxides. A two-stage preparation of an alloy through the synthesis of a suitable precursor may be exemplified by the chemical route used by Jena et al. (2004) in the preparation of a copper-nickel alloy. The alloy was prepared from an aqueous solution of the nitrates of copper and nickel dissolved in a minimum amount of water and allowed to dehydrate and decompose to their oxides at a temperature around 350°C for an hour. Samples of the mixed oxide powders thus formed were subjected to reduction by pure hydrogen. The reduced powder (apparently containing partially alloyed metals) was sintered at 1000°C. The effect of temperature (250-450°C) on the reduction of the co-formed oxides was studied. 

Co-reduction of mixed oxides with metals (Mg or Al) in a thermite-type reaction — this usually gives contaminated products including ternary borides, e.g. M07AI6B7. Alternatively, alkali metals or Ca can be used as reduc-tants, e.g. 

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