The open-source Reaction Mechanism Generator (RMG) software has recently been extended to include sulfur as a heteroatom. To account for the rich chemical reactivity of sulfur, representations of the different valances of sulfur combined with all possible bond types were defined. These representations, referred to as atom types, are used for reaction template and thermodynamic group additivity determinations, as well as for confining the allowed space of new structure generation. Electron delocalization, which is important for identification of reactive pathways, was described as transformations between different contributing structures including allylic, lone pair / radical, and lone pair / multiple bond shifts. Efforts to keep the vast combinatorial effect of all newly defined mesomerism pathways manageable and physical is discussed. These new capabilities of RMG were successfully applied to several test cases of SOx chemistry in combustion (including oxy-fuel combustion) where experimental speciation data is available, yet current literature modeling efforts require significant quantitative improvements. Further, reaction pathways describing the low temperature oxidation of dimethyl sulfide to sulfur dioxide as well as sulfoxides and sulfones were explored. This work presents the potential to automatically generate predictive chemical models for sulfur-containing species.

Sulfur reactivity and mesomerism in automated kinetic model generation

256th National Meeting (2018)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.