This contribution deals with a commercially scalable catalyst preparation method for the synthesis of a new generation of hybrid materials based on carbon-nanotubes-graphite. Commercial natural graphite in spherical or flake shapes, with varying particle sizes and textural properties, were used as catalyst support. They were impregnated with aqueous solutions containing cobalt nitrate in the presence of a non-ionic surfactant agent and then dried and calcined under controlled experimental conditions. Catalytic activity properties were evaluated in a rotary tube reactor using ethylene as a carbon source at a temperature of 650 °C and a residence time of 5 min. It was observed that the use of a surfactant agent in the impregnation step significantly improved the adsorption and dispersion of the active metal on the hydrophobic catalyst support surface, enabling the formation of a dense coating of carbon nanotubes on the graphite particles after the synthesis. The multi-walled carbon nanotubes (MWCNTs) showed diameters ranging from 10 to 20 nm and lengths between 5 and 10 µm, with most of them growing via the base-mode growth mechanism. The morphology properties of the graphite particles play a key role in influencing the active metal surface deposition, the MWCNT yield, and their aspect ratio properties
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