Experimental and kinetic study on flash pyrolysis of biomass via on-line photoionization mass spectrometry

Abstract

Experimental and kinetic study on flash pyrolysis of solid fuels is a challenge since its process usually occurs in a very few seconds. To do this successfully, a perfect combination of high heating rates, plug flow reactor, on-line sampling, real-time analysis and fast acquisition (e.g., < 300 ms/spectrum) is indispensable. In this work, a microfluidized-bed reactor (MFBR) was connected to the single photoionization time-of-flight mass spectrometer (SPI-TOFMS) to explore the kinetic process from flash pyrolysis of cellulose. The hydrodynamics of MFBR at different pyrolysis temperatures and with three model compounds were analyzed. The time-evolved profiles of primary tar from flash pyrolysis were recorded by SPI-TOFMS. The effect of experimental conditions (including pyrolysis temperature, transfer-line temperature and the type of carrier gas) on the kinetics of flash pyrolysis was systematically discussed. Besides, experimental measurements were also compared with kinetic modeling results, which shows a much better agreement between them than previous work. The obtained results prove that the MFBR combined with SPI-TOFMS is a potential and reliable method to experimentally study the flash pyrolysis of solid fuels.

Keywords

• Flash pyrolysis
• On-line analysis
• Biomass
• PI-MS
• Kinetic study