In-Detail Chemistry of Hydrocarbon Partial Oxidation Reaction by Plasma

In the plasma reforming of hydrocarbon fuels, especially in a partial oxidation process, characteristic parameters of the reaction can be sorted as plasma parameter and reactant condition parameter. Plasma parameter or electric power and voltage-current characteristic determines density of active chemical species such as electron, ions and excited molecules, electron energy and thermal energy converted from electrical energy. On the other hand, reactant condition such as oxygen to carbon ratio determines thermal energy released from reaction, reaction time scale and so on.

In this presentation, the effects of supplied power and oxygen to carbon ratio, that are representatives of the above parameters, on the in-detail chemistry of the reaction will be introduced. Investigated processes are partial oxidation reaction of diesel and methane.

In a plasma reforming process of liquid phase diesel, change in electric power affect initial stage of the reaction or fuel cracking and chain initiation process, but change in oxygen to carbon ratio affect overall thermal activation and chain termination. Control of electric power and oxygen to carbon ratio produces different composition of product, different size and distribution of soot particle and different thermal efficiency.

In a gas phase methane reforming, electric power and oxygen to carbon ratio simultaneously controls plasma mode of generation. This change in plasma mode affects in-detail chemistry of hydrogen abstraction and dehydrogenation of hydrocarbon species resulting in difference in the composition of final product especially in C₂ species.

The results on the analysis of the chemistry of plasma reforming can be used as a base data for optimum design of the process.