Experimental and kinetic modeling study on flow reactor pyrolysis of iso-pentanol: Understanding of iso-pentanol pyrolysis chemistry and fuel isomeric effects of pentanol

Flow reactor pyrolysis of iso-pentanol was conducted at 30 and 760 torr using synchrotron vacuum ultraviolet photoionization mass spectrometry (SVUV-PIMS). Pyrolysis products, especially radicals and enols, were identified and quantified. Olefins and oxygenated products (mainly aldehyde and enol) were found to be the two major product families in the pyrolysis of iso-pentanol. A kinetic model of iso-pentanol pyrolysis was developed and validated against the new experimental data. The rate of production (ROP) analysis and sensitivity analysis were conducted to understand the pyrolysis chemistry of iso-pentanol. The contribution of unimolecular decomposition reactions to the consumption of iso-pentanol is far less than that of H abstraction reactions at both pressures, which is similar to the situation in 2-methyl-1-butanol pyrolysis, but different from that in n-pentanol pyrolysis. Fuel isomeric effects on the pyrolysis chemistry of pentanol isomers were also investigated. Mole fraction profiles of fuels and major products were measured for other two typical pentanol isomers, i.e. n-pentanol and 2-methyl-1-butanol under the same pyrolysis conditions, while our previous models of n-pentanol and 2-methyl-1-butanol were used for the simulation. The initial decomposition temperatures of two branched pentanol isomers are slightly lower than that of n-pentanol at both pressures. The branched fuel structures strongly influence the molecular structures and formation pathways of fuel decomposition products such as C₄ and C₅ olefins, as well as the formation of benzene and fulvene.