(242f) Partial Oxidation of Methane

Methane can be converted to hydrogen and synthesis gas by several processes, i.e. steam reforming, autothermal reforming and partial oxidation. Steam reforming is the dominant process for the production of hydrogen and synthesis gas. However, current trends also point to a broadening of the market to include smaller units for on site production of hydrogen/synthesis gas. Methane is also a product from the decay or fermentation of organic material. Conversion of methane to hydrogen and synthesis gas is therefore interesting even for a possible future carbon-neutral energy chain. Catalytic partial oxidation of methane could be an interesting option for small scale units. Catalyst stability with respect to start-up and shut-down, heat integration and reliable and safe design is important issues in addition to activity and selectivity.

Methane is a very stable, symmetrical molecule. The C-H bonds are strong (425 kJ/mol) and it contains no functional group, magnetic moment or polar distribution to facilitate chemical attacks. Activation of methane by splitting of the C-H bond will require high temperatures and/or the use of oxidations agents. Catalysis will have to play an important role in most processes for methane conversion.

The presentation includes the use of Rh, Co and Ni as catalysts for partial oxidation. Rh catalysts are found to provide the best catalytic performance for catalytic partial oxidation. Due to the high cost of Rh, its efficient use is one of key issues. Reducing the Rh particle size could be a possible solution. However, obtaining high-temperature stable Rh nanoparticles against sintering is still a challenge. Alumina supported Co and Ni catalysts modified with noble and non-noble transition metals and metal oxides have also been studied. The studies include different preparation methods, catalyst characterization by different techniques and catalyst testing by fixed-bed and microchannel reactors.