Institute of Chemical Industry of Forest Products, Chinese Academy of Forestry , Key Lab. of Biomass Energy and Material, Jiangsu Province, National Engineering Lab. for Biomass Chemical Utilization, Key and Open Lab. on Forest Chemical Engineering , SFA, Nanjing 210042 , People's Republic of China.
United States Department of Agriculture (USDA) Forest Service , Southern Research Station , Pineville , Louisiana 71360 , United States.
J Agric Food Chem. 2019 Sep 4;67(35):9840-9850. doi: 10.1021/acs.jafc.9b03806. Epub 2019 Aug 26.
In the present study, methanolysis of poplar biomass was conducted for the selective transformation of hemicellulose and lignin, which leads to methyl glycosides (mainly C5 glycosides) and lignin fragments in the liquefied products that can be separated according to their difference in hydrophilicity. The distribution of methyl glycosides and delignification was dependent on the presence of acid catalysts and reaction temperatures. The obtained lignin fraction was separated into solid lignin fragments and liquid lignin oil according to their molecular weight distribution. Subsequently, directional conversion of methyl C5 glycosides into methyl levulinate was performed with dimethoxymethane/methanol as the cosolvent. A yield of 12-30% of methyl levulinate yield (based on the methyl glycoside) was achieved under these conditions. The remaining cellulose-rich substrate showed enhanced susceptibility to enzymatic hydrolysis, resulting in a yield of glucose of above 70%. Overall, the described strategy shows practical implications for the effective valorization of biomass.
在本研究中，对杨木生物质进行了甲醇解反应，以选择性转化半纤维素和木质素，从而在液化产物中得到甲基糖苷（主要为 C5 糖苷）和木质素片段，可根据其亲水性的差异进行分离。甲基糖苷的分布和脱木质素程度取决于酸催化剂的存在和反应温度。所得木质素部分根据其分子量分布，分离为固体木质素碎片和液体木质素油。随后，以二甲氧基甲烷/甲醇为共溶剂，将甲基 C5 糖苷定向转化为甲基戊酸酯。在这些条件下，甲基戊酸酯的产率（基于甲基糖苷）达到 12-30%。剩余富含纤维素的基质对酶水解的敏感性增强，葡萄糖的产率超过 70%。总体而言，所描述的策略对于生物质的有效增值具有实际意义。
