Promoting Effect of Co, Cu, Cr and Fe on Activity of Ni-Based Alloys in Catalytic Processing of Chlorinated Hydrocarbons

A series of sponge-like Ni_1−xM_x(M = Cu, Co, Cr, Fe; x = 0.00–0.10) alloys was prepared via synthetic routes with subsequent reduction in H₂atmosphere at 800–1000 °C. Formation of Ni-based solid solutions with face-cantered cubic (fcc) lattice of nickel was proven by X-ray diffraction analysis for all prepared samples. Ni_1−xM_xalloys were explored as precursors for self-organizing catalysts active in processing of 1,2-dichloroethane into carbon nanomaterial (CNM). According to kinetic studies of CNM growth performed at 600 °C, the catalytic activity of Ni_1−xM_xsamples changes as follows: Cr > Co–Cu ≫ Fe. Ni–Cr sample showed rather stable performance during 4 h whereas Ni–Co, Ni–Cu and Ni (reference) samples underwent rapid deactivation after ~150 min of reaction. The presence of the residual amount of Cr (0.5 at.%) found by energy dispersive X-ray microanalysis method in the composition of active Ni particles responsible for the growth of CNM is considered to be a key factor providing the stable catalytic performance. The obtained carbon product is represented by well-ordered segmented fibers (0.4–0.8 μm in diameter) and characterized with comparatively high textural parameters (surface area 290–330 m²/g, pore volume 0.43–0.57 cm³/g).