The selective oxidation of methane and propene over α-Bi2Mo3O12
Date
2007-03
Authors
Nel, Jacobus
Journal Title
Journal ISSN
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Publisher
Stellenbosch : University of Stellenbosch
Abstract
The catalytic selective oxidation of hydrocarbon molecules is the process where a selectively
oxidized intermediate molecule is formed instead of the thermodynamically favoured total
oxidation products, in the presence of a suitable catalyst. Examples are the selective
oxidation of methane to synthesis gas at moderate temperatures, for which a catalyst is still
needed and the selective oxidation of propene to acrolein over α-Bi2Mo3O12. The selective
oxidation of propene over α-Bi2Mo3O12 occurs via a Mars-van Krevelen mechanism where the
bulk oxygen in the catalyst is inserted into the propene molecule and leaves as part of the
product, while being replaced with gaseous oxygen.
From an economic perspective there is a need to produce synthesis gas from methane at low
temperatures. It was seen in the literature that α-Bi2Mo3O12 is a mixed metal oxide that might
be capable of achieving this. The feasibility of the selective oxidation of methane to synthesis
gas with α-Bi2Mo3O12 was therefore investigated. However, it was found that the selective
oxidation of methane over α-Bi2Mo3O12 is not feasible at moderate temperatures. To
circumvent the problem of producing synthesis gas at low temperatures a membrane reactor
was suggested that might be able to produce synthesis gas at moderate temperatures with
conventional selective methane oxidation catalysts that thermodynamically favours carbon
dioxide formation at low temperatures.
No time on-stream experiments had been done previously for the selective oxidation of ...
Description
Thesis (MScEng (Process Engineering))--University of Stellenbosch, 2007.
Keywords
Dissertations -- Process engineering, Theses -- Process engineering, Heterogeneous catalysis, Methane -- Oxidation, Propene -- Oxidation