State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, People's Republic of China.
State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, People's Republic of China.
Bioresour Technol. 2020 Aug;309:123351. doi: 10.1016/j.biortech.2020.123351. Epub 2020 Apr 8.
In this study, lignin with different phenolic hydroxyl contents and five model compounds are pyrolyzed to investigate the effect of the interaction of phenolic hydroxyl with a benzene ring on lignin pyrolysis. The results demonstrated that phenolic hydroxyl can reduce the stability of lignin and promote the elimination of the side chain on lignin during pyrolysis. The repolymerization during lignin pyrolysis, which results in increased activation energy and char yield during pyrolysis, can be mainly attributed to phenolic hydroxyl. Meanwhile, the repolymerization because of phenolic hydroxyl is obviously affected by the electron cloud density of the benzene ring. The repolymerization caused by the phenolic hydroxyl can be effectively reduced by increasing the electron cloud density. Furthermore, regulation of the product distribution obtained via lignin pyrolysis by changing the electron cloud density of the benzene ring and the phenolic hydroxyl content in lignin is proposed.
在这项研究中，我们对具有不同酚羟基含量的木质素和五种模型化合物进行了热解，以研究酚羟基与苯环相互作用对木质素热解的影响。结果表明，酚羟基可以降低木质素的稳定性，并促进木质素热解过程中侧链的消除。木质素热解过程中的重聚合反应会导致热解过程中的活化能和焦炭产率增加，这主要归因于酚羟基。同时，由于酚羟基引起的重聚合反应明显受到苯环的电子云密度的影响。通过增加苯环和木质素中酚羟基的电子云密度，可以有效地降低酚羟基引起的重聚合反应。此外，还提出了通过改变苯环的电子云密度和木质素中酚羟基的含量来调节木质素热解产物分布的方法。
