Preparation of vapor-grown carbon fibers in straight form by floating catalyst method in Linz-Donawitz converter gas

Abstract

In order to obtain vapor-grown carbon fibers (VGCFs) in straight form by the floating catalyst method, experimental and analytical examinations were carried out. It was supposed that the suppression of disturbances in the carrier gas flow due to thermal convection in the region where primary filaments were formed was important to prepare straight fibers and that thermal convention would be suppressed by preheating the carrier gas before introducing into the reaction region. The preparation of benzene-derived VGCFs in Linz-Donawitz converter gas, which was obtained from our steelmaking plants, was performed using a reactor equipped with a preheater. Straight fibers were obtained under conditions in which thermal convection appeared to be suppressed. Numerical simulation using the finite element method indicated that the flow in the reactor with the preheater was laminar, while thermal convection occurred in the reactor without the preheater.