Lignin represents the most abundant source of renewable aromatic resources, and the depolymerization of lignin has been identified as a prominent challenge to produce lowmolecular-mass aromatic chemicals. Herein, we report a nanostructured MoO x /CNT, which can serve as an efficient catalyst in hydrogenolysis of enzymatic mild acidolysis lignins (EMALs) derived from various lignocellulosic biomass, thus giving monomeric phenols in high yields (up to 47 wt %). This catalyst showed high selectivity toward phenolic compounds having an unsaturated substituent, because the cleavage of C−O bonds in β-O-4 units is prior to reduction of double bonds by MoO x /CNT under a H 2 atmosphere, which was confirmed by examination of lignin model compound reactions. The effects of some key parameters such as the influence of solvent, temperature, reaction time, and catalyst recyclability were also examined in view of monomer yields and average molecular weight. This method constitutes an economically responsible pathway for lignin valorization, which is comparable to the performance of precious-metal catalytic systems in terms of activity, reusability, and biomass feedstock compatibility.

An ordered mesoporous aluminosilicate with completely crystalline zeolite pore wall structure, denoted as OMZ-1, was successfully synthesized by recrystallization of SBA-15 using in situ formed CMK-5 as the hard template. The role of carbon material not only serves as a hard template to preserve ordered mesoporous structure but also kinetically controls the crystallization process to form large crystals.

Methanol synthesis via carbon dioxide (CO2) reduction is challenging and important because this technology can convert CO2 by solar-or wind-generated hydrogen into liquid fuel. The present work introduces the visible light as an external stimulus and for the first time demonstrates that methanol synthesis over Cu/ZnO catalysts can be effectively promoted by solar energy under atmospheric pressure.Experimental and theoretical studies document that hot electrons were photo-excited by localized surface plasmon resonance (LSPR) on Cu nanoparticles and such photo-excited hot electrons could transfer to ZnO through the metal-support interfaces.The hot electrons on Cu and ZnO synergistically facilitated the activation of reaction intermediates. Consequently, the activation energy was reduced by 40% and the methanol synthesis activity was promoted by 54%. This work provides a new strategy towards synthesis of liquid fuel via CO2 reduction under low pressure and sheds new light on the mechanism of photo-mediated catalysis.

Producing monomeric phenols from lignin biopolymer depolymerization in a detachable and efficient manner comes under the spotlight on the fullest utilization of sustainable lignocellulosic biomass. Here, we report a low-loaded and highly dispersed Ru anchored on a chitosan-derived N-doped carbon catalyst (RuN/ZnO/C), which exhibits outstanding performance in the reductive catalytic fractionation of lignocellulose. Nearly theoretical maximum yields of phenolic monomers from lignin are achieved, corresponding to TON as 431 molphenols molRu−1, 20 times higher than that from commercial Ru/C catalyst; high selectivity toward propyl end-chained guaiacol and syringol allow them to be readily purified. The RCF leave high retention of (hemi)cellulose amenable to enzymatic hydrolysis due to the successful breakdown of biomass recalcitrance. The RuN/ZnO/C catalyst shows good stability in recycling experiments as well as after a harsh hydrothermal treatment, benefiting from the coordination of Ru species with N atoms. Characterizations of the RuN/ZnO/C imply a transformation from Ru single atoms to nanoclusters under current reaction conditions. Time-course experiment, as well as reactivity screening of a series of lignin model compounds, offer insight into the mechanism of current RCF over RuN/ZnO/C. This work opens a new opportunity for achieving the valuable aromatic products from lignin and promoting the industrial economic feasibility of lignocellulosic biomass.

Lignin oil from lignin-first biorefinery with a reusable catalyst was applied to obtain jet fuel aromatics and polyurethane feedstock.