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The paper considers the use of deactivated nickel-containing catalysts based on Al2O3 as a significant raw material resource of one of the most important metals. The research highlights the features of this secondary nickel source that determine the acceptable methods of processing such raw materials. The effect of fluxing additives on the properties of the melt containing catalysts prepared beforehand has been studied subject to limitations as to their list (lime, fluorspar) in order to implement a pyrometallurgical method of metal extraction featuring by a relatively small amount of additives themselves. Due to induction heating used in combination with a graphite crucible, adding the total amount of fluorspar and marble additives close in mass made it possible to obtain the melt at a temperature slightly higher than the nickel melting temperature. In this case, the level of metal losses was about 2 %, which indicates the applicability of this method in laboratory conditions to ensure correct incoming analysis. It was proposed to use the pyrometallurgical method on an industrial scale using closed arc heating. To confirm this conclusion, experiments were conducted with a representative (more than 100 kg) amount of catalyst using a tailored arc furnace. Graphite chips were used as a reducing agent. The necessity of electrical matching of the load with the power source resulted in some adjustment of the fluxing additive ratio towards a reduction of calcium oxide content. As a result of a series of experiments, nickel with an up to 5 % iron admixture, similar in composition to the metal formed in the graphite crucible, was obtained. The presence of iron was caused by the fundamentally distinctive capability of the pyrometallurgical technology to reduce unstable compounds. Therefore it was suggested to use this metal for ferronickel production. The use of scarce fluorspar is justified by the fact that the resulting slag can be in demand in the production of fluxes for the electroslag remelting process.

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In this work, the technology of Al-Gd alloys production has been developed, in which gadolinium is added as an alloying element during induction melting or in the composition of Gd2O3 disperse particles in the complex use of powder metallurgy and foundry technologies. The design of Vibration-jet agitator (VJA) and technology of its use for introduction of disperse particles into aluminum melts were developed. Aluminum alloys and dispersion-strengthened composites containing gadolinium have been obtained, their structure and neutron absorption properties has been studied.

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