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Updated: Jul 16, 2026
09:48
Original Experimental Approach for Assessing Transport Fuel Stability
Published on: October 21, 2016
Oligoterpenes Oxidation: Integrating Thermal Analysis Experiments and Ab Initio Kinetics
Jonathan Honorien1,2, Dario Vassetti1,2, François Toche3
1Aramco Fuel Research Center, Rueil-Malmaison92852, France.
The Journal of Physical Chemistry. A
|July 14, 2026
Summary
This study reveals how isoprene unit number affects fuel autoxidation. A new kinetic model clarifies complex reaction pathways, improving predictions for fuel safety and additive design.
Area of Science:
- Chemical Kinetics
- Combustion Chemistry
- Organic Chemistry
Background:
- Autoxidation of isoprenoid oligomers is crucial for fuel and lubricant stability.
- Understanding the influence of molecular structure on oxidation pathways is essential for predicting performance and safety.
Purpose of the Study:
- To investigate the impact of isoprene unit number on the reactivity and selectivity of multiphase autoxidation.
- To elucidate product formation pathways and identify key reaction channels in pristane and squalane oxidation.
- To develop an integrated framework for predicting the autoxidation of isoprenoid oligomers.
Main Methods:
- Evolved gas analysis using coupled thermogravimetric analysis/simulated thermolytic ionization/gas chromatography-mass spectrometry (TGA/STI/GC-MS).
- First-principles-augmented kinetic modeling for liquid-phase oxidation coupled with a gas-phase mechanism via a reaction-evaporation model.
- Ab initio calculations to study reaction complex interactions and transition states.
Main Results:
- Identified two new hydroperoxide (ROOH) decomposition channels: dissociative abstraction and radical Hock rearrangement.
- Developed a kinetic model that successfully predicts dominant product peaks and aromatic formation via branched-alkene recombination.
- Revealed that the bimolecular ROOH decomposition pathway is significant below 130 °C, while gas-phase oxidation dominates above 225 °C.
- Observed bimodal product distributions in squalane linked to a second oxidation phase.
Conclusions:
- The integrated framework clarifies the oxidation network of isoprenoid oligomers, reducing uncertainty in acid formation kinetics.
- Insights enhance the predictive reliability of kinetic models for fuel/lubricant storage and additive design.
- The study provides a foundation for tailoring autoxidation pathways for specific applications.
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