A comprehensive experimental and kinetic modeling study of tert-butanol combustion

Abstract

The combustion of tert-butanol was studied experimentally in this work, including flow reactor pyrolysis at 30–760Torr, laminar flat premixed flame at 30Torr, coflow methane/tert-butanol diffusion flame at atmospheric pressure, and laminar flame speed at 1–10atm. Synchrotron vacuum ultraviolet photoionization mass spectrometry (SVUV-PIMS) was applied in the investigation of pyrolysis and flame, and the schlieren technique was used in the measurement of laminar flame speed. A detailed kinetic model consisting of 209 species and 1486 reactions was developed in this work, which can predict the decomposition of tert-butanol and the formation of aromatics over wide temperature and pressure ranges. Kinetic analysis illustrates that the unimolecular decomposition of tert-butanol is the most important and sensitive reaction class in different combustion modes, which readily produce the most important aromatic precursors: tert-butanol→iso-butene→2-methylallyl→allene→propargyl. As a result, the production of benzene, phenyl radical, and benzyl radical are all enhanced in the combustion of tert-butanol compared to those of other butanol isomers. The self-combination of propargyl and the combination of propargyl with other resonantly stabilized radicals are the key steps of aromatics formation in the combustion of tert-butanol.