The possible use of leaching residue from leaching deep-sea nodules in SO2/H2SO4/H2O medium as a low-cost adsorbent of heavy metals (Pb(II), Cd(II), Cu(II), Ni(II), Co(II), As(V)) was studied. The leaching residue was found to be an effective adsorbent for all of the tested elements; however, it was inactive in the solution containing As(V). The chemical activation of adsorbent in 10 vol. % HCl resulted in the greatest improvement of adsorption properties, while the activation in 10 vol. % HNO3 and heat treatment at 250 °C did not significantly affect the sorption characteristics of treated adsorbents compared with the original leaching residue. After HCl activation, the maximal adsorption capacities for lead (12.0 mg/g at pH 5.0 after 1 h), nickel (3.1 mg/g at pH 5.5 after 4 h) and cobalt (2.0 mg/g at pH 5.0 after 2 h) were achieved. Additional mechanical treatment connected with HCl activation provided the highest adsorption capacities for cadmium (11.5 mg/g at pH 4.0) and copper (5.7 mg/g at pH 4.5). Coprecipitation of Fe/Al-based particles on the surface of the leaching residue increased As(V) removal of the adsorbent. Surface coating based on AlIII was extremely effective, causing the increase of the adsorption capacity from 0 with the original leaching residue, to 28.1 mg/g (pH 7.0, 24 min). Kinetics studies showed the rapid progress of adsorption for Pb(II), Cd(II), and As(V) in tens of minutes, while the adsorption of Cu(II), Ni(II) and Co(II) approached a steady state after 2 h.

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NiTi alloy is characterized by many interesting properties assiciated with the shape memory behaviour. Since this material can be superelastic and recover the shape after deformation, it can be considered as potential matrix for composites. In this work, the possibility of preparation of NiTi matrix composites was tested. Two kinds of materials were studied -NiTi matrix composite reinforced by ceramic particles and in-situ composite containing NiTi and hard Ti2Ni phase obtained by reactive sintering of Ni+Ti mixture.

NiTi is a shape memory alloy used mainly in medicine. Many applications can be also found in industrial sector. Its properties are considerably determined by structure and phase composition. It was found that production by powder metallurgy method leads to creation of required phase NiTi, but certain amount of hard and brittle phase Ti2Ni is also formed. Its presence in the structure affects mechanical properties of the alloy and it might widen the applicability of material to a new industrial branches. Suitable preparation method of composite material NiTi-Ti2Ni with the possibility to control amount of generated phase Ti2Ni would allow regulation of material mechanical properties.