Ran Wang,Chong Li,Jianxiang Wu,Wei Du,Tao Jiang,Yizhou Yang,Xuejing Yang,Ming Gong
Sustainable polymer production is essential for a carbon-neutral society. cis,cis-Muconic acid is attracting growing interest as a biomass-derived platform molecule with direct access to adipic acid and terephthalic acid, prominent monomers of commercial polymers. Here, a sustainable route of electro-reforming biorenewable catechol to cis,cis-muconic acid with concurrent H2 production has been proposed. By using a CuO foam electrode, a high cis,cis-muconate yield of 90% and a high faradaic efficiency of 87% can be achieved under ambient conditions without external oxidant. Zn2+ coordination with the catechol is central to the yield and selectivity. In a combinatory analysis via steady-state electrochemical kinetics, in situ spectroscopy, and theoretical calculation, we revealed that the reaction ensemble of catechol electrooxidation involves three major processes of polymerization, ring cleavage, and depolymerization, in which Zn2+ coordination is highly effective in delaying polymerization and promoting ring cleavage toward cis,cis-muconate. The catecholate coordinated to the Zn2+ cations reallocated its electron density with partial structural deformation to accelerate the electron transfer and facilitate the OH– nucleophilic attack. A practical two-electrode system was eventually demonstrated to efficiently and stably electro-reform catechol into isolable cis,cis-muconic acid and hydrogen, providing solutions for polymer sustainability via utilizing alternative biomass resources and electrified processes.
Chenggu Cai,Pengju Huo,Pingxiang Zhong,Lei Ma,Zhaoxian Xu,Maozhi Ren,Zuoren Yang,Fuguang Li
Cottonseed hulls (CSHs) emerge as a promising lignocellulosic feedstock for synthesizing high-value products through the biorefinery approach. However, scant attention has been devoted to a detailed characterization of their primary components, particularly the intricate lignin fraction. This study conducted a comprehensive compositional analysis of CSHs, primarily delving into the intricate characterization of lignin samples extracted via organosolv and alkaline methods. The investigation encompassed the fundamental lignin unit composition, inter-chemical linkages, molecular weight distribution, and functional group profile. Further analysis revealed that alkaline-extracted lignin possesses a higher abundance of low-molecular-weight lignin fragments and hydroxyl groups than organosolv-extracted lignin. This distinct characteristic renders alkaline lignin a favorable candidate for producing chemicals and functional materials via bioconversion and chemical modification. To demonstrate this, alkaline lignin was successfully valorized into cis , cis -muconate and white lignin material. This study provides valuable insights into the fundamental characteristics of CSH lignin, uncovering its potential for the synthesis of value-added chemicals and materials.
危险品化学品经营许可证（带存储）