The Features of the CCVD of Trichloroethylene Over Microdispersed Ni and Ni–Mo Catalysts

Self-organizing catalytic systems are promising for synthesis of carbon nanomaterials via catalytic chemical vapor deposition. The precursors of catalysts, 100Ni and 96Ni–4Mo, were synthesized by reductive thermolysis at 800 °C and tested in the H₂-assisted catalytic pyrolysis of C₂HCl₃ to produce carbon nanofibers. The reaction temperature was varied in a range of 475–675 °C. The kinetics of carbon accumulation over the prepared catalysts was studied to reveal the effect of Mo on the catalytic performance of nickel. It was shown that the process is characterized by the presence of induction period, and the addition of molybdenum to nickel leads to a shortening of this period in ~ 70% along with an increase in the C₂HCl₃ decomposition rate and boosting the carbon yield. The maximum yield of the carbon nanomaterial obtained after 2 h of the C₂HCl₃ decomposition over 96Ni–4Mo alloy at 600 °C was as high as 89 g/g_cat. The presence of Mo in the catalyst’s composition also leads to a decrease in activation energy value from 79 to 55 kJ/mol. The longevity tests performed at 600 °C for 7 h showed that the bimetallic 96Ni–4Mo alloy provides productivity of 259 g/g_cat, which is 2.2 times higher than for the monometallic 100Ni catalyst. According to transmission and scanning electron microscopies, the obtained carbon nanomaterial is predominantly represented by long filaments attached to submicron-sized catalytic particles. The carbon nanofibers are characterized by a defective and non-uniform segmented secondary structure and possess high specific surface area (up to 385 m²/g).