Huang Jingtao, Zhao Chengke, Lu Fachuang
State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, China.
Guangdong Engineering Research Center for Green Fine Chemicals, Guangzhou 510640, China.
Polymers (Basel). 2018 Sep 28;10(10):1077. doi: 10.3390/polym10101077.
Lignin is recognized as a good sustainable material because of its great abundance and potential applications. At present, lignin hydrogenolysis is considered as a potential but challenging way to produce low-molecular-mass aromatic chemicals. The most common linkage between the structural units of lignin polymer is the β-O-4 aryl ether, which are primary or even only target chemical bonds for many degradation processes. Herein, a Pd-Fe₃O₄ composite was synthesized for catalytic hydrogenolysis of β-O-4 bond in lignin. The synthesized catalyst was characterized by XRD, XPS, and SEM and the lignin depolymerization products were analyzed by GC-MS. The catalyst showed good catalytic performance during the hydrogenolysis process, lignin dimer was degraded into monomers completely and a high yield of monomers was obtained by the hydrogenolysis of bagasse lignin. More importantly, the magnetic catalyst was separated conveniently by magnet after reaction and remained highly catalytically efficient after being reused for five times. This work has demonstrated an efficient & recyclable catalyst for the cleavage of the β-O-4 bond in lignin providing an alternative way to make better use of lignins.
木质素因其丰富的储量和潜在的应用价值而被认为是一种良好的可持续材料。目前，木质素氢解被视为一种生产低分子量芳香化学品的潜在但具有挑战性的方法。木质素聚合物结构单元之间最常见的连接方式是β-O-4芳基醚键，它是许多降解过程的主要甚至唯一目标化学键。在此，合成了一种Pd-Fe₃O₄复合材料用于催化木质素中β-O-4键的氢解。通过XRD、XPS和SEM对合成的催化剂进行了表征，并通过GC-MS分析了木质素解聚产物。该催化剂在氢解过程中表现出良好的催化性能，木质素二聚体完全降解为单体，通过甘蔗渣木质素的氢解获得了高产率的单体。更重要的是，磁性催化剂在反应后可以通过磁铁方便地分离，并且在重复使用五次后仍保持高催化效率。这项工作展示了一种用于裂解木质素中β-O-4键的高效且可回收的催化剂，为更好地利用木质素提供了一种替代方法。
