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Title: Quantifying the effect of difluoromethane on ignition delay times of propane
Poly- and Perfluorinated alkyl substances (PFAS) pose environmental and public health concerns. While incineration remains the most common PFAS remediation method, the complete combustion and pyrolysis mechanism of PFAS is unknown. This study aims to expand our understanding of the kinetics of gas-phase PFAS incineration by measuring the effect of difluoromethane (CHF) on propane ignition delay times (IDTs). The ignition delay times were measured by OH* emission and end-wall pressure time histories behind the reflected shock wave. Different concentrations of CH2F2 were mixed with fuel-lean propane-oxygen mixtures diluted in argon. Experiments were conducted at a nominal reflected shock pressure of P5 = 1 atm and reflected shock temperatures of 1200 < T5 < 1800 K. A new detailed chemical kinetic mechanism is presented. 135 new rate constants were computed using RRKM/ME theory, based upon stationary points computed using ANL0. The new mechanism is in excellent agreement with the measured ignition delay time. A novel sensitivity analysis helps to explain the elementary steps by which CH2F2 increases the ignition delay time.  more » « less
Award ID(s):
1751720
PAR ID:
10555090
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
Elsevier
Date Published:
Journal Name:
Proceedings of the Combustion Institute
Volume:
40
Issue:
1-4
ISSN:
1540-7489
Page Range / eLocation ID:
105497
Subject(s) / Keyword(s):
CH2F2 PFAS Ignition delay time Propane Fluorine
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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