Mechanism of porous filamentous carbon granule formation on catalytic hydrocarbon decomposition

摘要

We have sutided the growth of catalytic filamemtary carbon granules forned on methane decomposition over Ni catalysis. As a result,a hunder-fold increase in the particle volume can be obtained. It was established that as Ni concentration in the initial catalyst increases, the solidity of catalytic filamentary carbon (CFC) aggregates ,formed on methane decomposition, increases. In the course of CFC formation on the finely-disperse catalyst of high nickel conent, the inner structure of the growing granule transfroms from the dense agglomerate of nickel particles into a dense carbon filament packing with rather large single internal cavities (cracks). On the granule surface there is a layer whose filament packing remains loose. We propose the physical models of granule fornation.