Integrated catalytic hydroconversion of three crop stalks to valuable oxygenated organic chemicals

Abstract

Two flexible regulation systems were designed and used for the integrated catalytic hydroconversion (CHC) of lignocellulose to valuable oxygenated organic chemicals. Under the dual constraints of initial H2 pressure (IHP) and temperature, three crop stalks can be almost completely degraded over a hydrothermally stable Ru/La(OH)3 in one-pot, while the synergetic transfer of active hydrogen effectively promotes the cleavage of >C-O- bridged bonds in organic matter with highly complex structures during this period. As a result, abundant >Cal-O- (>32%) and >C=O (>24%) derived platform chemicals such as alkanols, cyclanols, carboxylic acids, and esters were obtained at high IHP and low temperature. Correspondingly, various >Car-O- (>50%) and >C=O (>30%) derived platform chemicals such as phenols, alkoxy-substituted phenols, ketones, and carboxylic acids dominated the derived bio-oils at low IHP and high temperature. The designed selective CHC strategies have the characteristics of convergent conversion to the two major derivative chemical demand directions. Therefore, these two atom-economic and effective degradation approaches are conducive to obtaining abundant functional small molecules, which can be further converted to various downstream platform products.