Exploration on Thermal Decomposition of Cyclopentanone: A Flow Reactor Pyrolysis and Kinetic Modeling Study

Pyrolysis
of cyclopentanone was investigated in a flow reactor
at temperatures of 875–1428 K and pressures of 0.04 and 1 atm.
Dozens of pyrolysis products including isomers, radicals, and aromatics
were detected using synchrotron vacuum ultraviolet photoionization
mass spectrometry (SVUV-PIMS). Among them, two groups of keto–enol
tautomers were observed; one is cyclopentanone and 1-cyclopentenol,
and the other one is 1,4-cyclopentadien-1-ol, 2-cyclopeten-1-one and
3-cyclopeten-1-one. A detailed kinetic model of cyclopentanone was
also developed with the consideration of the theoretical progress
of key reactions in this work and in the literature. Based on the
experimental and simulated results, the main consumption pathways
of cyclopentanone and main formation pathways of critical products
were explored. Special attention has been paid to the mole fraction
ratios of CO-to-fuel and ethylene-to-CO, as CO and ethylene are two
of the most abundant primary decomposition products. In addition,
the successive decomposition of the diradical produced from the Cβ–Cγ bond dissociation reaction
of cyclopentanone was found to be crucial to the formation of C3 species. The recombination of these unsaturated small species
also accounts for the abundant formation of 1,3-cyclopentadiene and
aromatic species in cyclopentanone pyrolysis.