Zhou Hao, Tan Liping, Fu Yingjuan, Zhang Huayong, Liu Na, Qin Menghua, Wang Zhaojiang
State Key Laboratory of Bio-based Materials and Green Papermaking, Qilu University of Technology, Shandong Academy of Sciences, 3501 Daxue Rd, Jinan, 250353, P.R. China.
Laboratory of Organic Chemistry, Taishan University, 525 Dongyue Street, Taian, 271021, P.R. China.
ChemSusChem. 2019 Mar 21;12(6):1213-1221. doi: 10.1002/cssc.201802803. Epub 2019 Feb 20.
Whole valorization of carbohydrate and lignin from biomass was achieved by rapid flow-through fractionation (RFF) within 15 min. Wheat straw was effectively deconstructed into its principle components without degradation by using easily recyclable aqueous formic acid (72 wt %) at 130 °C. The obtained cellulose-rich solid showed a nearly complete glucan recovery and 73.8 % glucose conversion after enzymatic hydrolysis. Xylan also reached full recovery with negligible furfural formation with a sum of 80 % of oligo/mono xylose in spent liquor and 20 % of xylan remaining in the solid. Up to 75.4 % lignin was dissolved in the spent liquor and further fractionated into water-insoluble (WIL) and water-soluble lignin (WSL) by dilution with water. WIL showed a non-condensed and well-preserved structure with 84.5 % β-O-4 remaining, which is believed to be beneficial for catalytic conversion into low-molecular-weight chemicals and fuels. The concentration of employed formic acid was below the formic acid/water azeotrope, and therefore the reaction medium could be restored through simple distillation. Together with the joint valorization of lignin and carbohydrates, the presented RFF is a promising process for sustainable biorefinery.
通过快速流通分级分离（RFF）在15分钟内实现了生物质中碳水化合物和木质素的全价值利用。在130℃下使用易于回收的甲酸水溶液（72 wt%），小麦秸秆有效地分解为其主要成分且无降解。所得富含纤维素的固体在酶水解后显示出近乎完全的葡聚糖回收率和73.8%的葡萄糖转化率。木聚糖也实现了完全回收，糠醛生成量可忽略不计，废水中低聚/单木糖总量占80%，20%的木聚糖留在固体中。高达75.4%的木质素溶解在废水中，并通过用水稀释进一步分离为水不溶性木质素（WIL）和水溶性木质素（WSL）。WIL显示出非缩合且保存良好的结构，β-O-4保留率为84.5%，据信这有利于催化转化为低分子量化学品和燃料。所用甲酸的浓度低于甲酸/水共沸物，因此反应介质可通过简单蒸馏恢复。连同木质素和碳水化合物的联合价值利用，所提出的RFF是一种有前景的可持续生物精炼工艺。
