Influences of Reaction Temperature, Duration, and Catalysts on Hemicellulose Pyrolysis Products

Fast pyrolysis experiments were conducted on xylan (XY) using pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) to explore influences of the reaction temperature, duration, and catalysts on product distributions from XY pyrolysis. The results show that temperature and duration can notably influence the classes and yields of compounds generated by the pyrolysis of hemicellulose. Pyrolysis at 500–600 °C for a duration of 5–20 s is conducive to improving the yields of condensable volatiles from hemicellulose pyrolysis. In all catalytic experiments, when taking HZSM-5 as the catalyst, alcohols (37.31%), carbohydrates (27.61%), and hydrocarbons (3.71%) have the highest contents while aldehydes (9.76%), ketones (2.20%), esters (0%), furans (0%), and N-compounds (4.09%) possess the lowest contents. MCM-41 promotes production of aldehydes (59.94%), acids (5.11%), ketones (6.92%), phenols (0.30%), ethers (0.61%), and N-compounds (18.70%) while inhibiting generation of alcohols (1.21%) and carbohydrates (3.79%). ZrO2 is conducive to increasing the content of furans (2.23%) while decreasing the content of acids (0.64%).