Filamentous carbon growth inhibition

Inhibition of filamentous carbon growth on metal surfaces by addition of titanium oxide has been reported previously (10). In these experiments the titanium oxide was in the fully oxidized state and was an effective physical barrier toward filament formation, provided that the temperature was kept below 920 K. Above this temperature, the oxide tended to spall, and as bare metal was exposed to the gas phase, prolific filament growth occurred. In the present study we have combined electron microscopy studies with... 

In a recent study, Baker and Chludzinski (10) used the basis of this proposed mechanism to develop methods of inhibiting the growth of filamentous carbon. The approach was aimed at the introduction of additives into the metal catalyst particles, which had the potential of reducing the rate of the critical steps involved in the growth process i.e., carbon solubility or carbon diffusion through the catalyst particle. Among several additives investigated, silica was the most effective as it reduced the rates of both of these processes. 

Li et reported a novel method of obtaining nickel oxide particles with controlled crystalline size and fibrous shape, highly dispersed on in situ produced carbon, inhibiting further growth of Ni particles. On the other hand, Ni/CFC (filamentous carbon) catalysts were shown to have sufficient efficiency in low-temperature methane decomposition. Thus, the use of CFG, whose textural properties can be modified by their activation with Hg or COg, opens up the possibility of its application as a support in heterogeneous catalysis. Methane decomposition over Ni-loaded activated carbon (AC) was also investigated. XRD results showed absence of NiO with only Ni metal crystallites formed in the catalyst even if calcined in Ar, which eliminates the inevitable reduction step with other supports. However, the formation of NisC during the process leads to deactivation of the catalysts. Filamentous carbon formation is... 

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