质子溶剂促进木质素在质子离子液体中的去甲基化

IF 13.2 1区工程技术 Q1 ENGINEERING, CHEMICAL

Chemical Engineering Journal Pub Date : 2025-09-22 DOI:10.1016/j.cej.2025.168825

Yichen Liu, Wanting Zhao, Yuting Shi, Jian Sun

{"title":"质子溶剂促进木质素在质子离子液体中的去甲基化","authors":"Yichen Liu, Wanting Zhao, Yuting Shi, Jian Sun","doi":"10.1016/j.cej.2025.168825","DOIUrl":null,"url":null,"abstract":"Ethanolamine-based protic ionic liquids (PILs) have shown promising efficiency for lignin demethylation, offering a greener alternative to traditional halogenated Brønsted acids for polyphenol production. For precipitation of demethylated lignin, protic anti-solvents (e.g., water, methanol) are typically added and then completely removed by distillation to recover PILs. Considering that protic solvents could affect the ionicity and viscosity of the PILs, their addition was hypothesized to promote S<sub>N</sub>2-based demethylation by further increasing the extent of ion dissociation of the PIL. Herein, typical protic co-solvents were evaluated for enhancing lignin demethylation in ethanolamine-based PILs. Commercial alkali lignin (AL) and corncob alkali lignin (CAL) were studied for comparison. Co-solvents improved demethylation efficiency in the order of water > methanol > ethanol > isopropanol. A 50.0 wt% water-[EOA][OAc] system achieved a threefold increase in AL demethylation efficiency (25.3 %, PhOH content = 5.05 %) compared to [EOA][OAc], due to enhanced ionicity (confirmed by the Walden plot slope) and lower viscosity. Notably, water exhibited a bifunctional role, including co-solvent for lignin demethylation and anti-solvent for lignin precipitation. Besides, due to the decreased solubility of lignin in [EOA][OAc]-water system, an efficient heterogenous demethylation of lignin was achieved. Structural analysis of lignin further revealed that water addition promoted lignin linkage cleavage and condensation. For CAL, water increased demethylation efficiency from 45.4 % to 67.2 %, indicating the good substrate versatility of [EOA][OAc]-water system. Overall, this study improves the environmental and operational viability of lignin demethylation with [EOA][OAc], and highlights the critical role of tuning PIL ionicity and solvent environment in biomass processing.","PeriodicalId":270,"journal":{"name":"Chemical Engineering Journal","volume":"44 1","pages":""},"PeriodicalIF":13.2000,"publicationDate":"2025-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Protic solvent-boosted lignin demethylation in protic ionic liquids\",\"authors\":\"Yichen Liu, Wanting Zhao, Yuting Shi, Jian Sun\",\"doi\":\"10.1016/j.cej.2025.168825\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"Ethanolamine-based protic ionic liquids (PILs) have shown promising efficiency for lignin demethylation, offering a greener alternative to traditional halogenated Brønsted acids for polyphenol production. For precipitation of demethylated lignin, protic anti-solvents (e.g., water, methanol) are typically added and then completely removed by distillation to recover PILs. Considering that protic solvents could affect the ionicity and viscosity of the PILs, their addition was hypothesized to promote S<sub>N</sub>2-based demethylation by further increasing the extent of ion dissociation of the PIL. Herein, typical protic co-solvents were evaluated for enhancing lignin demethylation in ethanolamine-based PILs. Commercial alkali lignin (AL) and corncob alkali lignin (CAL) were studied for comparison. Co-solvents improved demethylation efficiency in the order of water > methanol > ethanol > isopropanol. A 50.0 wt% water-[EOA][OAc] system achieved a threefold increase in AL demethylation efficiency (25.3 %, PhOH content = 5.05 %) compared to [EOA][OAc], due to enhanced ionicity (confirmed by the Walden plot slope) and lower viscosity. Notably, water exhibited a bifunctional role, including co-solvent for lignin demethylation and anti-solvent for lignin precipitation. Besides, due to the decreased solubility of lignin in [EOA][OAc]-water system, an efficient heterogenous demethylation of lignin was achieved. Structural analysis of lignin further revealed that water addition promoted lignin linkage cleavage and condensation. For CAL, water increased demethylation efficiency from 45.4 % to 67.2 %, indicating the good substrate versatility of [EOA][OAc]-water system. Overall, this study improves the environmental and operational viability of lignin demethylation with [EOA][OAc], and highlights the critical role of tuning PIL ionicity and solvent environment in biomass processing.\",\"PeriodicalId\":270,\"journal\":{\"name\":\"Chemical Engineering Journal\",\"volume\":\"44 1\",\"pages\":\"\"},\"PeriodicalIF\":13.2000,\"publicationDate\":\"2025-09-22\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Chemical Engineering Journal\",\"FirstCategoryId\":\"5\",\"ListUrlMain\":\"https://doi.org/10.1016/j.cej.2025.168825\",\"RegionNum\":1,\"RegionCategory\":\"工程技术\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"ENGINEERING, CHEMICAL\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Chemical Engineering Journal","FirstCategoryId":"5","ListUrlMain":"https://doi.org/10.1016/j.cej.2025.168825","RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ENGINEERING, CHEMICAL","Score":null,"Total":0}

引用次数: 0

摘要

基于乙醇胺的质子离子液体（PILs）在木质素去甲基化方面表现出了良好的效率，为多酚生产提供了传统卤化Brønsted酸的绿色替代品。对于去甲基化木质素的沉淀，通常添加质子反溶剂（例如，水，甲醇），然后通过蒸馏完全去除以回收pil。考虑到质子溶剂会影响PIL的离子性和粘度，我们假设它们的加入可以通过进一步增加PIL的离子解离程度来促进sn2基的去甲基化。本文评价了典型的protic助溶剂对乙醇胺基pil中木质素去甲基化的促进作用。对商品碱木质素（AL）和玉米芯碱木质素（CAL）进行了比较研究。助溶剂的脱甲基效率依次为水、甲醇、乙醇、异丙醇。与[EOA][OAc]相比，50.0 wt%的水-[EOA][OAc]体系的AL去甲基化效率提高了三倍（25.3 %，PhOH含量 = 5.05 %），这是由于离子性增强（由瓦尔顿图斜率证实）和粘度降低所致。值得注意的是，水具有双重功能，包括木质素去甲基化的助溶剂和木质素沉淀的反溶剂。此外，由于木质素在[EOA][OAc]-水体系中的溶解度降低，实现了木质素的高效异相去甲基化。木质素的结构分析进一步表明，水的加入促进了木质素键的裂解和缩合。对于CAL，水将去甲基化效率从45.4% %提高到67.2% %，表明[EOA][OAc]-水体系具有良好的底物通用性。总体而言，本研究提高了[EOA][OAc]木质素去甲基化的环境和操作可行性，并强调了PIL离子性和溶剂环境在生物质加工中的关键作用。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

查看原文本刊更多论文

Protic solvent-boosted lignin demethylation in protic ionic liquids

Ethanolamine-based protic ionic liquids (PILs) have shown promising efficiency for lignin demethylation, offering a greener alternative to traditional halogenated Brønsted acids for polyphenol production. For precipitation of demethylated lignin, protic anti-solvents (e.g., water, methanol) are typically added and then completely removed by distillation to recover PILs. Considering that protic solvents could affect the ionicity and viscosity of the PILs, their addition was hypothesized to promote S_N2-based demethylation by further increasing the extent of ion dissociation of the PIL. Herein, typical protic co-solvents were evaluated for enhancing lignin demethylation in ethanolamine-based PILs. Commercial alkali lignin (AL) and corncob alkali lignin (CAL) were studied for comparison. Co-solvents improved demethylation efficiency in the order of water > methanol > ethanol > isopropanol. A 50.0 wt% water-[EOA][OAc] system achieved a threefold increase in AL demethylation efficiency (25.3 %, PhOH content = 5.05 %) compared to [EOA][OAc], due to enhanced ionicity (confirmed by the Walden plot slope) and lower viscosity. Notably, water exhibited a bifunctional role, including co-solvent for lignin demethylation and anti-solvent for lignin precipitation. Besides, due to the decreased solubility of lignin in [EOA][OAc]-water system, an efficient heterogenous demethylation of lignin was achieved. Structural analysis of lignin further revealed that water addition promoted lignin linkage cleavage and condensation. For CAL, water increased demethylation efficiency from 45.4 % to 67.2 %, indicating the good substrate versatility of [EOA][OAc]-water system. Overall, this study improves the environmental and operational viability of lignin demethylation with [EOA][OAc], and highlights the critical role of tuning PIL ionicity and solvent environment in biomass processing.

求助全文

通过发布文献求助，成功后即可免费获取论文全文。去求助

来源期刊

Chemical Engineering Journal 工程技术-工程：化工

CiteScore

21.70

自引率

9.30%

发文量

6781

审稿时长

2.4 months

期刊介绍： The Chemical Engineering Journal is an international research journal that invites contributions of original and novel fundamental research. It aims to provide an international platform for presenting original fundamental research, interpretative reviews, and discussions on new developments in chemical engineering. The journal welcomes papers that describe novel theory and its practical application, as well as those that demonstrate the transfer of techniques from other disciplines. It also welcomes reports on carefully conducted experimental work that is soundly interpreted. The main focus of the journal is on original and rigorous research results that have broad significance. The Catalysis section within the Chemical Engineering Journal focuses specifically on Experimental and Theoretical studies in the fields of heterogeneous catalysis, molecular catalysis, and biocatalysis. These studies have industrial impact on various sectors such as chemicals, energy, materials, foods, healthcare, and environmental protection.