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Group Additive Kinetics for Hydrogen Transfer Between Oxygenates
Paschalis D Paraskevas1,2, Maarten K Sabbe1, Marie-Françoise Reyniers1
1†Laboratorium voor Chemische Technologie, Universiteit Gent, Technologiepark 914 9052, Zwijnaarde, Belgium.
The Journal of Physical Chemistry. A
|June 9, 2015
Summary
This study develops group additivity models to predict hydrogen abstraction reaction rates for oxygenates. These models accurately estimate kinetics across a wide temperature range, crucial for biomass conversion processes.
Area of Science:
- Chemical Kinetics
- Combustion Chemistry
- Biomass Conversion
Background:
- Hydrogen abstraction reactions involving oxygenates are vital in biomass conversion.
- Accurate kinetic data is needed for modeling these complex processes.
Purpose of the Study:
- To develop group additivity models for predicting Arrhenius parameters of hydrogen abstraction reactions in oxygenates.
- To cover a wide temperature range (300-2500 K) and various oxygenate compound classes.
Main Methods:
- Utilized group additivity based on CBS-QB3 calculations for O--H--C and O--H--O transfer reactions.
- Determined 43 group additivity values from 118 reactions.
- Incorporated 37 corrections for cross-resonance effects in transition states.
Main Results:
- The developed models accurately reproduce ab initio calculated and experimental rate coefficients.
- Mean factor of deviation was approximately 3 for a set of 85 rate coefficients.
- The models provide reliable predictions for hydrogen abstraction kinetics.
Conclusions:
- Group additivity models offer an accurate and efficient method for predicting oxygenate reaction kinetics.
- This approach is valuable for understanding and optimizing biomass conversion pathways.
- The models enhance the predictive capability for combustion and atmospheric chemistry involving oxygenates.
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