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  • Mechanism of Thermal Decomposition of Hydroxyacetone: A Flash Pyrolysis Vacuum Ultraviolet Photoionization Time-of-Flight Mass Spectrometry and Density Functional Theory Study
Title: Mechanism of Thermal Decomposition of Hydroxyacetone: A Flash Pyrolysis Vacuum Ultraviolet Photoionization Time-of-Flight Mass Spectrometry and Density Functional Theory Study
he thermal decomposition mechanism of hydroxyacetone from 850 to 1390 K was examined by using flash pyrolysis vacuum ultraviolet photoionization time-of-flight mass spectrometry combined with density functional theory calculation. The results showed that keto–enol tautomerisms could occur prior to the thermal decomposition of hydroxyacetone. The decomposition pathways of hydroxyacetone and its isomer, 2-hydroxypropanal were characterized. The thermal decomposition reactions started at about 950 K. The homolysis reactions related to the cleavage of the CCO–CCOH bond of hydroxyacetone and 2-hydroxypropanal, as well as CH3 loss of hydroxyacetone, dominated the initial decomposition reactions. The subsequent decompositions of the radical intermediates generated by the initial homolysis decompositions were the major secondary decomposition reactions. The formation pathways of small molecules, such as H2, CH4, H2O, and HCHO, were proposed to proceed via molecular elimination reactions facilitated by the active α-H atoms. These elimination reactions were not negligible at high temperatures above 1230 K.  more » « less
Award ID(s):
2155232
PAR ID:
10583662
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
ACS
Date Published:
Journal Name:
The Journal of Physical Chemistry A
Volume:
127
Issue:
45
ISSN:
1089-5639
Page Range / eLocation ID:
9590 to 9600
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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