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Published on: July 18, 2017
Reaction pathways of propene pyrolysis
1School of Natural and Applied Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi 710072, People's Republic of China.
Journal of Computational Chemistry
|January 19, 2010
Summary
This study details gas-phase reaction pathways for pyrolytic carbon formation from propene. Radical attacking chain reactions are the most favorable pathways, with high energy barriers for C(3) production.
Area of Science:
- Chemical kinetics
- Materials science
- Computational chemistry
Background:
- Pyrolytic carbon production is crucial for advanced materials.
- Understanding propene pyrolysis mechanisms is key to optimizing carbon deposition.
- Detailed kinetic studies are needed to elucidate complex reaction networks.
Purpose of the Study:
- To investigate the gas-phase reaction pathways in pyrolytic carbon formation from propene.
- To identify the most favorable reaction mechanisms and energy barriers.
- To provide a theoretical basis for experimental optimization of pyrolytic carbon synthesis.
Main Methods:
- Density functional theory (DFT) at B3PW91/6-311G(d,p) for structure determination.
- Frequency and intrinsic reaction coordinate (IRC) analyses for transition state confirmation.
- G3(MP2) model chemistry for accurate energy barrier calculations.
- Statistical thermodynamics for thermodynamic property determination.
Main Results:
- 110 transition states and 50 intermediates were identified in the propene pyrolysis mechanism.
- Radical attacking chain reactions were found to be the dominant pathways.
- Highest energy barriers for C(3), C(2), and C production at 1200 K were determined to be 203.4, 174.1, and 181.4 kJ/mol, respectively.
- Calculated energy barriers align with experimental observations.
Conclusions:
- The study elucidates the detailed gas-phase reaction network for pyrolytic carbon formation from propene.
- Radical chain mechanisms are critical for efficient carbon deposition.
- The identified energy barriers provide valuable insights for controlling pyrolytic carbon synthesis.
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