The use of a conventional porous catalyst in the study of the pyrolysis and partial oxidation of hydrocarbons is complicated because reactions take place both on the catalyst surface and in the gas phase (including pores). A non-porous nickel mesh catalyst was used to study the catalytic pyrolysis and partial oxidation of CH4, C2H6 and C3H8. Our experimental results strongly indicate that the radicals formed on the catalyst surface could easily desorb from the catalyst surface when the gas film around the mesh wires was thinned by increasing the gas flow rate passing through the mesh. The desorption of radicals from the catalyst surface greatly limited the formation of coke on the catalyst surface, leading to sustained high catalytic activities even during the pyrolysis of pure hydrocarbons. The catalyst could have dual roles. It could act as a chain reaction terminator by providing a surface for the chain termination reactions to take place. The mesh catalyst could also act as a chain reaction re-initiator by providing additional radicals into the gas phase in which the desorbed radicals re-initiate and participate in the chain reactions.
About the Speaker: Chun-Zhu Li obtained his PhD in 1993 from the Imperial College of Science, Technology and Medicine (University of London). After 2 years as a Rothmans Foundation Fellow working in the CSIRO Division of Coal and Energy Technology, he joined Monash University in 1996. He is now a Professor in the Department of Chemical Engineering in Monash University. Prof Li is a Fellow of the Institution of Chemical Engineers (FIChemE) and a Fellow of the Australian Institute of Energy (FAIE). He has co-authored more than 170 papers in international journals and conference proceedings. He has also edited a book Advances in the Science of Victorian Brown Coal. He is a member of the editorial board for 3 international journals.
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