Speaker
Prof.
G. Barney Ellison
(University of Colorado)
Description
The study of the pyrolysis of complex fuels is carried out in a heated, CW micro-reactor. Reactions are studied in a resistively-heated SiC microtubular (0.66 mm i.d. x 2.5 cm) flash pyrolysis flow reactor from 1000 – 1800 K. The standard reactor operating conditions of 280 sccm He flow have been studied by computational fluid dynamics. [International J. Phys. Chem. 2014, (submitted)]. The gas flow has been found to be laminar and the residence time in the reactor is of the order 25 — 150 μsec.
The reaction mechanism for the pyrolysis of cyclopentadienone, C5H4=O, has been studied. Cyclopentadienone is an intermediate in the high temperature oxidation of aromatic fuels and in the thermal cracking of biomass. The molecular structure of C5H4=O is known by microwave spectroscopy (J. Phys. Chem. Letts. 2014, 5, 2201-2207); polarized IR spectroscopy has established the vibrational force field (J. Phys. Chem A 2014, 118, 708-718). We have studied the pyrolysis of C5H4=O over a 1000 K — 1600 K
range. We find two channels: Reaction (1) C5H4=O (+ M) → CO + 2 HC≡CH and Reaction (2) C5H4=O (+ M) → CO + HC≡C-CH=CH2. The decomposition of C5H4=O is
shown to be unimolecular and the products, HC≡CH from (1) and HC≡C-CH=CH2 from (2), were detected in situ by means of tunable synchrotron photoionization mass spectroscopy at LBNL’s ALS. The temperature-dependent branching ratio of
[HC≡CH]/[HC≡C-CH=CH2] was established and the ratio of k1/k2 was measured. Separate iPEPICO measurements at the PSI’s SLS were used to measure IE(C5H4=O) = 9.408 ± 0.011 eV.
Primary author
Prof.
G. Barney Ellison
(University of Colorado)
