Vapor grown carbon fibers from pyrolysis of hydrocarbons: Modeling of filament growth and poisoning

Abstract

A kinetic scheme has been proposed as a feasible model to explain the lengthening step in vapor grown carbon fibers from the pyrolysis of hydrocarbons. The two-parameter model assumes that the filaments lengthen by the reaction of a pyrolysis product with the growing filaments, and that the growth process ceases when the catalyst particle attached to the growing filament is poisoned by some reactive species in the gas phase. The model results show that the rate of filament growth is initially high and decreases monotonically. The final average filament length is found to depend only on the ratio of the rate of growth to the rate of poisoning. The model results can satisfactorily correlate the limited experimental data available in the open literature.