With the aim to support the experimental tests in a circulating fluidized bed pilot plant, the pyrolysis processes of coal, corn, and coal-corn blend have been studied with an online pyrolysis photoionization time-of-flight mass spectrometry (Py-PI-TOFMS). The mass spectra at different temperatures (300 - 800 °C) as well as time-evolved profiles of selected species were measured. The pyrolysis products such as alkanes, alkenes, phenols, aromatics, as well as nitrogen- and sulfur-containing species were detected. As temperature rises, the relative ion intensities of high molecular weight products tend to decrease, while those of aromatics increase significantly. During the co-pyrolysis, coal can promote the reaction temperature of cellulose in corn. Time evolved profiles demonstrate that coal can affect pyrolysis rate of cellulose, hemicellulose, and lignin of corn in blend. This work shows that Py-PI-TOFMS is a powerful approach to permit a better understanding of the mechanisms underlying the co-pyrolysis of coal and biomass.

The real-time and online detection of pyrolysis products of coal, corn, and coal corn blend have been studied by Py-PI-TOFMS technique. As temperature rises, the signals of aromatics, such as benzene and toluene, increase significantly for pure coal and corn pyrolysis. For coal-corn blend, coal can promote the reaction temperature of cellulose in corn. The time-evolved profiles reveal that the coal can affect the pyrolysis rate of cellulose, hemicellulose, and lignin from corn in blend. According to this work, the potential for process control of target products is possible by monitoring reaction parameters, such as temperature and reaction time.