An experimental and kinetic modeling study on pyrolysis of chlorobenzene

An experimental and kinetic modeling investigation of the pyrolysis of chlorobenzene (PHICL) was performed with a flow reactor using synchrotron vacuum ultraviolet photoionization mass spectrometry in the temperature range of 800–1507 K and pressures of 30 to 760 torr. Eighteen pyrolysis products were identified and quantified. A detailed kinetic model describing the PHICL pyrolysis process was developed and validated against the available experimental results. The sensitivity analysis of PHICL pyrolysis shows that the PHICL consumption is most sensitive to the unimolecular decomposition reaction R2PHICL=o-C6H4+Cl at 30 Torr. The H-abstraction reaction of PHICL+Cl=R2PHICL+HCl plays a dominant role in PHICL consumption at 760 Torr. The mole distribution analysis and rate of production (ROP) analysis shows that PHICL tends to be decomposed via unimolecular decomposition reactions to produce small molecules such as o-C6H4, C4H4, C4H2, and C2H2 at 30 Torr; while with pressure increasing, recombination reactions of chlorophenyl (RxPHICL (x = 2–4)) radicals forming C12H8Cl2, and ipso-addition reactions of chlorophenyl/phenyl to PHICL yielding C12H8Cl2/C12H9Cl are critical to the consumption of the precursor, further leading to the formation of tricyclic chlorinated aromatic C18H11Cl.