This work develops the technique and technology of modification by ferroalloys of floatable nickel catalysts of hydrogenation of benzene. It in detail studies the influence of the nature of metal of the catalyst, the modifying additives, the size of particles, technological parameters. They worked up reliable data on phase, granulometric and chemical structures, porous structure explaining activity, selectivity and stability of catalysts. The synthesized nickel catalysts are tested in the course of hydrogenation of benzene to cyclohexane in the liquid phase.