Catalytic decomposition of methane is a promising process that allows the simultaneous production of hydrogen and carbon nanomaterials with no COx emissions. In this work, for the first time, the possibility of promoting Ni-containing composite materials based on an organic matrix of polyvinyl alcohol (PVA) with MgO was demonstrated. The amount of MgO promoter varied from 1 to 10% by weight of Ni. The synthesized catalysts were characterized by the following methods: elemental analysis, TPR-H2, XRD, FTIR spectroscopy, Raman spectroscopy, SEM, TEM, SSA, and Raman fluorescence enhancement spectroscopy. The catalytic activity of the materials was tested in the pure CH4 decomposition reaction. Promotion with MgO contributes to an increase in the H2 yield per unit mass of Ni from 1.23 to 2.55 mol/gNi. The optimal content of the promoting component was 0.3% wt., which corresponded to 1% wt. from Ni. Carbon formed during CH4 decomposition in the form of nanotubes. The obtained carbon nanotubes (CNTs) were characterized by the following methods: XRD, Raman spectroscopy, SEM, and TEM. The length of the CNTs varies from 1 to 6 μm, the outer diameter ranges from 40 to 60 nm, and the inner diameter ranges from 10 to 20 nm.
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