Investigation of multi-walled carbon nanotubes catalytic activity by means of the model aerobic oxidation reaction Scientific paper

Abstract

This study investigates the synthesis of multi-walled carbon nano­tubes (MWCNTs) via chemical vapor deposition (CVD) using propane gas and evaluates their catalytic efficiency in oxidation reactions. The MWCNTs were synthesized in a laboratory-scale CVD reactor under optimized conditions, with ferrocene used as a precursor to incorporate 9.8 wt. % iron into the nanotube structure. The catalytic activity of the synthesized MWCNTs was evaluated in the cumene oxidation reaction, demonstrating remarkable performance even at relatively low temperatures. This enhanced catalytic efficiency is attributed to the presence of iron compounds within the MWCNT channels, which are pre­sumed to act as active sites for the reaction. Among the catalysts studied, the G-CVD-1 sample containing 9.8 wt. % iron showed the highest performance, accelerating the oxidation reaction by a factor of 23 compared to the uncatal­yzed process. In comparison, the L-CVD-184 sample, with a lower iron content of 3.7 wt. %, achieved a 16-fold increase in reaction rate relative to the same uncatalyzed baseline. These values indicate that the iron concentration within MWCNTs plays a crucial role in determining their catalytic efficiency, with higher iron loading providing significantly better activity. This study demon­strates that iron-modified MWCNTs possess significant potential as durable and efficient catalysts for oxidation reactions.