Revealing the critical role of radical-involved pathways in high temperature cyclopentanone pyrolysis

• Main Authors: Dong, Xiaorui (Author), Ninnemann, Erik (Author), Ranasinghe, Duminda S (Author), Laich, Andrew (Author), Greene, Robert (Author), Vasu, Subith S. (Author), Green Jr, William H (Author)
• Other Authors: Massachusetts Institute of Technology. Department of Chemical Engineering (Contributor)
• Format: Article
• Language: English
• Published: Elsevier BV, 2020-08-14T21:18:29Z.
• Subjects: Article
• Online Access: Get fulltext

Cyclopentanone (CPO) is a promising biofuel for spark-ignition engines due to its ring strain and high auto-ignition resistance. Understanding CPO decomposition is crucial for building a high-temperature combustion model. Here we present a comprehensive kinetic model for high-temperature pyrolysis of CPO with verified results from high-pressure shock tube (HPST) measurements. The time-histories of carbon monoxide (CO), ethylene (C₂H₄), and CPO absorbances over the temperature range of 1156-1416 K and pressure range of 8.53-10.06 atm were measured during current experiments. A corresponding detailed kinetic model was generated using the Reaction Mechanism Generator (RMG) with dominant unimolecular/radical-involved decomposition pathways from either previous studies or quantum calculations within the current work. The obtained model containing 821 species and 79,859 reactions exhibited a good agreement with the experimental results. In this study, the absorbance ratio between C₂H₄ and CO was used as an important factor to validate models and to prove that radical-involved bimolecular pathways were as significant as unimolecular decomposition of CPO. The rate of production (ROP) analysis showed H radicals play a major role in the decomposition, and the whole decomposition process could be divided into three stages based on the H radical concentration. The insights from present work can be used to generate a better CPO combustion model and help evaluate CPO as an advanced biofuel.
Department of Energy (Grant DE-EE007982)