Mechanism of pyrocarbon formation on the soot surface

Abstract

In the article a mechanism of pyrocarbon formation on the soot surface by the decomposition of hydrocarbon gases is suggested. The mechanism involves the formation of decomposition products in the gas phase and their adsorption on the active centers of the soot. The defects of a crystal lattice formed on the contact borders of crystallites can be these active centers. Three models of pyrocarbon formation on the surface of a single soot particle and on the surface of soot structures are considered in detail. The results of mathematical calculations and experimental data are also given in the article. We explained the reason of polyextreme dependence of specific surface changing of technical carbon during the pyrocarbon formation process. Substrate influence on the pyrocarbon deposition regularities on the carbon material surface is also established. These regularities must be taken into account at the production of carbon materials if the stage of pyrocarbon formation is available.

Keywords

• soot
• technical carbon
• pyrocarbon
• hydrocarbon gas
• specific surface