Lignin was isolated from wheat straw via organosolv process and further transferred to monophenolic compounds via oxidative conversion. Wheat straw lignin (WSL) with purity at 91.4 wt% was acquired in the presence of heterogeneous and recyclable catalyst of Amberlyst-45. WSL was characterized by infrared spectrometer (IR), nuclear magnetic resonance spectroscopy (NMR) including H NMR and C NMR spectra. The results showed that WSL possesses typical syringyl (S), guaiacyl (G), and -hydroxyphenyl (H) units, and it is mainly composed of S and G units. The product distribution was dependent on the composition of WSL. Derivatives from S and G units were found to be the main products. The oxidative conversion of WSL was performed by varying oxidant and catalyst. Both the formation of monophenolic compounds and aromatic aldehydes were enhanced by combining oxidants and catalysts. The composite catalyst composed of NaOH/NaAlO was effective for the oxidation of WSL in the presence of nitrobenzene and atmospheric pressure air. The total yield of monophenolic compounds reached up 18.1%, and yields at 6.3 and 5.7% for syringaldehyde and vanillin were achieved, respectively.
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http://dx.doi.org/10.1002/fsn3.1633 | DOI Listing |
Appl Microbiol Biotechnol
January 2025
Engineering Biology Research Center, Kobe University, 1-1 Rokkodai, Nada, Kobe, 657-8501, Japan.
The fermentative production of valuable chemicals from lignocellulosic feedstocks has attracted considerable attention. Although Saccharomyces cerevisiae is a promising microbial host, it lacks the ability to efficiently metabolize xylose, a major component of lignocellulosic feedstocks. The xylose oxidative pathway offers advantages such as simplified metabolic regulation and fewer enzymatic steps.
View Article and Find Full Text PDFChem Rev
January 2025
Department of Chemical & Biomolecular Engineering, University of California, Irvine, California 92697, United States.
The reactions critical for the energy transition center on the chemistry of hydrogen, oxygen, carbon, and the heterogeneous catalyst surfaces that make up electrochemical energy conversion systems. Together, the surface-adsorbate interactions constitute the electrochemical interphase and define reaction kinetics of many clean energy technologies. Practical devices introduce high levels of complexity where surface roughness, structure, composition, and morphology combine with electrolyte, pH, diffusion, and system level limitations to challenge our ability to deconvolute underlying phenomena.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
Northeast Forestry University, Chemical Engineering and Resource Utilization, CHINA.
Electrochemical 5-hydroxymethylfurfural (HMF) oxidation reaction (HMFOR) offers a promising route to transform biomass into value-added chemicals. However, the competing oxygen evolution reaction (OER) greatly limits the HMFOR selectivity. Herein, we report a facile doping strategy to engineer oxygen intermediates adsorption on amorphous NiFe alloys to boost highly selective electrochemical HMF oxidation to produce 2,5-furandicarboxylic acid (FDCA), among which, amorphous Mn-doped NiFeB alloy displays a low HMFOR onset potential of 1.
View Article and Find Full Text PDFRSC Adv
January 2025
Department of Nanoscience and Engineering, Center for Nano Manufacturing, Inje University 197 Inje-ro Gimhae Gyeongnam-do 50834 Republic of Korea
Recently, lithium-sulfur batteries have captivated those in the energy storage industry due to the low cost and high theoretical capacity of the sulfur cathode (1675 mA h g). However, to enhance the practical usability of Li-S batteries, it is crucial to address issues such as the insulating nature of sulfur cathodes and the high solubility of lithium polysulfides (LiPS, LiS , 4 ≤ ≤ 8) that cause poor active sulfur utilization. Designing innovative sulfur hosts can effectively overcome sulfur bottlenecks and achieve stable Li-sulfur batteries.
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January 2025
Faculty of Materials Science and Technology, University of Science Ho Chi Minh City Vietnam
Infrared (IR) photodetectors play an important role in many fields such as industry, medicine, security, Achieving high response and maintaining stability in the device performance while reducing materials cost are required for the practical use of optical sensors. This study presents the development of a low-cost but high-performance IR photodetector based on a hybridization of up-conversion microparticles of NaYF:Tm,Yb (UCMPs) and reduced graphene oxide material (RGO). In this combination, UCMPs play the role of absorbing photons from 980 nm excitation light, generating electron-hole pairs, which are useful for sensing applications.
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