Fast Pyrolysis of Corn Stalks at Different Growth Stages to Selectively Produce 4-Vinyl Phenol and 5-Hydroxymethyl Furfural

摘要

Fast pyrolysis of specific corn stalk (CS) materials offered a promising and convenient way to selectively produce two valuable compounds, i.e., 4-vinyl phenol (4-VP) and 5-hydroxymethyl furfural (5-HMF). In this study, CSs at five different growth stages were prepared, including trefoil stage (30 days), elongation stage (70 days), heading stage (80 days), ripening stage (100 days) and full ripening stage (120 days). Moreover, three fractions were separated from CSs except the CS of trefoil stage, including leaf, stem bark and stalk pulp. Fast pyrolysis of CSs were performed via pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) technique. The results indicated that the pyrolytic characteristics of these CSs differed greatly from each other. 4-VP and 5-HMF were the two major products at low pyrolysis temperatures. Stem bark at elongation stage was the best feedstock for selective production of 4-VP, with a yield of 4.98 wt% at 300 degrees C. Stalk pulp at ripening stage was optimal for selective production of 5-HMF, with a yield of 4.87 wt% at 300 degrees C. In addition, a brief mechanism exploitation for the formation of 4-VP and 5-HMF was also conducted with the aid of CS sample characterization.Graphical Abstract