Effect of excess oxygen in plasma reforming of diesel fuel

This study investigated the plasma reforming process for diesel focusing on the relative ratio of oxygen to fuel. Excess O₂ in the partial oxidation process is known to increase the combustion portion, resulting in a decreased yield of H₂ and CO. However, in this parametric investigation, there was no apparent decrease in the H₂ and CO selectivity. Adding O₂ did not increase the portion of combustion in the overall reaction. Rather, an excess O₂ supply from partial oxidation stoichiometry resulted in an increase in CO₂ selectivity without a reduction in CO selectivity. Heavy hydrocarbon species were identified as a source of CO₂ in excess O₂ conditions due to preferential oxidative cracking. The additional oxidation of C₁-C₄ species by excess O₂ provided a minor contribution to CO₂. Excess O₂ affects soot generation characteristics by suppressing the agglomeration of soot particles, resulting in smaller particle generation. However, the oxidation of soot particles does not provide a major contribution to increasing the CO₂ selectivity. The results show that in a real reforming process, controlling the O₂ supply does not have a strong effect on the process selectivity of hydrogen.