Biomass reforming processes in hydrothermal media

[摘要] (cont.) Also, the degradation pathway of glucose was found to be altered, with the significant product hydroxymethylfurfural being suppressed with the addition of glycine. The reactive form of glucose is the acyclic, aldehydoglucose form. Glucose can also exist as an unreactive, cyclic form, which dominates at room temperature, making up over 99.99% of the aqueous equilibrium composition. However, this equilibrium is unknown at elevated temperatures and pressures. A preliminary computational chemistry study was undertaken to predict this equilibrium under hydrothermal conditions. The acyclic form was predicted to rise to be of comparable prevalence to the cyclic forms. The study indicates that this was caused by two main effects, a change in the relative stability imparted by the decreased dielectric constant of water, and by an entropic effect in which the much larger number of conformers that are possible in the acyclic state become more energetically populated at higher temperatures.

[发布机构] Massachusetts Institute of Technology