Carbonization of the toluene soluble fraction of fullerene soot into a disk

Carbonization of toluene soluble fraction in the fullerene soot was examined in the disk at the bottom of the test tube. Such a carbonization was found to increase the carbon yield to 94% at 900°C and 92% at 2400°C. The carbon yield was also found to be influenced by the thickness of the disk and the heating rate. All these results indicate that carbonization competes with sublimation. The carbon disk thus prepared gave an appearance of glass-like carbon and had an apparent density of 1.36 g cm^-3 at 900°C and 1.29 g cm^-3 at 2400°C. The reduction of the density by graphitization reflects the hollow spheres surrounded by their graphite layers in the graphitized disk.