Towards directional pyrolysis of xylan: Understanding the roles of alkali/alkaline earth metals and pyrolysis temperature

To identify the roles of alkali/alkaline earth metals (AAEM) and reaction temperature during pyrolysis of hemicellulose, the effects of AAEM doping on the pyrolysis behaviors, kinetics, and product yields of xylan at different pyrolysis temperatures were assessed. The results demonstrated that the yields of anhydrosugars from pyrolysis of xylan were dependent on the AAEM cations and their doping concentrations. Demineralization achieved the directional conversion of xylan into xylosan at 300 °C. The doping of even 0.05 mmol/g AAEM significantly suppressed their formation. The yields of xylosan from pyrolysis of xylan doped with different AAEM cations decreased in the following order: Mg2+