Kinetics of Carbon Multi‐wall Nanotube Synthesis by Catalytic Pyrolysis of Methane

Abstract

By method of isothermal gravimetry at 600–700°C, CH4 concentration 32–100% in Ar and 91–100% in H2 under atmospheric pressure the kinetics of CH4 pyrolysis under Ni/La2O3 catalysts is studied. Estimated apparent activation energy of reaction is 73 kJ/mol for fresh catalyst and 71 kJ/mol for aged one. The reaction order on CH4 changes from 1.05 at 600°C to 1.3 at 700°C. The influence of H2 concentration on the reaction rate is more complicated. On the basis of kinetics measurements continuously working laboratory‐scale reactor with gas and catalyst counter‐flow is constructed and tested.