| Autor: |
Wang CH; NanoScienece Technology Center , University of Central Florida , 12424 Research Parkway , Orlando , Florida 32826 , United States., Panteleev SV; N. I. Lobachevsky State University of Nizhny Novgorod , Gagarin Av. 23 , Nizhny Novgorod 603950 , Russia., Masunov AE; NanoScienece Technology Center , University of Central Florida , 12424 Research Parkway , Orlando , Florida 32826 , United States.; Department of Chemistry , University of Central Florida , 4111 Libra Dr. , Orlando , Florida 32816 , United States.; South Ural State University , Lenin pr. 76 , Chelyabinsk 454080 , Russia.; National Research Nuclear University MEPhI , Kashirskoye shosse 31 , Moscow 115409 , Russia., Allison TC; Southwest Research Institute , San Antonio , Texas 78238 , United States., Chang S; KEPCO Research Institute , Daejeon 34050 , Korea., Lim C; Hanwha Power Systems , Seongnam , Gyeonggi 13488 , Korea., Jin Y; Hanwha Power Systems , Seongnam , Gyeonggi 13488 , Korea., Vasu SS; Center for Advanced Turbomachinery and Energy Research (CATER), Mechanical and Aerospace Engineering , University of Central Florida , Orlando , Florida 32816 , United States. |
| Abstrakt: |
Fossil fuel oxy-combustion is an emerging technology where the habitual nitrogen diluent is replaced by high-pressure supercritical CO 2 (sCO 2 ), which increases the efficiency of energy conversion. In this study, the chemical kinetics of the combustion reaction C 2 H 6 ⇌ CH 3 + CH 3 in the sCO 2 environment is predicted at 30-1000 atm and 1000-2000 K. We adopt a multiscale approach, where the reactive complex is treated quantum mechanically in rigid rotor/harmonic oscillator approximation, while environment effects at different densities are taken into account by the potential of mean force, produced with classical molecular dynamics (MD). Here, we used boxed MD, where enhanced sampling of infrequent events of barrier crossing is accomplished without application of the bias potential. The multistate empirical valence bond model is applied to describe free radical formation accurately at the cost of the classical force field. Predicted rates at low densities agree well with the literature data. Rate constants at 300 atm are 2.41 × 10 14 T -0.20 exp(-77.03 kcal/mol/ RT) 1/s for ethane dissociation and 8.44 × 10 -19 T 1.42 exp(19.89 kcal/mol/ RT) cm 3 /molecule/s for methyl-methyl recombination. |
