• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of Wood Chemistry and Technology >LIGNIN AND OTHER AROMATIC SUBSTANCES RELEASED FROM SPRUCE WOOD DURING PRESSURIZED HOT-WATER EXTRACTION, PART 2: STRUCTURAL CHARACTERIZATION
【24h】

LIGNIN AND OTHER AROMATIC SUBSTANCES RELEASED FROM SPRUCE WOOD DURING PRESSURIZED HOT-WATER EXTRACTION, PART 2: STRUCTURAL CHARACTERIZATION

机译：加压热水提取过程中云杉木材释放的木质素和其他芳香物质，第2部分：结构表征

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Extraction of ground spruce sapwood with pressurized hot water in an accelerated solvent extractor (ASE) at 170 degrees C during 20, 60, and 100 min resulted in isolation of galactoglucomannans and aromatic substances, including lignin. The isolated lignin preparations were characterized by spectrometric (UV, FT-IR, H-1 NMR, liquid and solid-state C-13 NMR), chromatographic (RP-HPLC, HP-SEC, GC-FID, and GC-MS), conventional pyrolysis, thermally assisted hydrolysis, and methylation techniques in tandem with GC-MS, and classical wet chemistry (methoxyl groups, total and phenolic hydroxyl groups, derivatization followed by reductive cleavage-DFRC). The content of beta-O-4 bonds in isolated lignins was similar to that in MWL and their proportion decreased with extraction time. The oxidation of isolated lignins and content of total hydroxyl groups were significantly increased with extraction time. The lignin structure underwent condensation and demethylation reactions during hot-water extraction. The induction of new phenylcoumaran substructures was proposed in isolated lignins.
机译：在170、20、60和100分钟的加速溶剂萃取器（ASE）中用加压热水萃取云杉边材，结果分离了半乳葡甘露聚糖和包括木质素在内的芳香物质。分离的木质素制剂的特征在于光谱法（UV，FT-IR，H-1 NMR，液态和固态C-13 NMR），色谱法（RP-HPLC，HP-SEC，GC-FID和GC-MS） ，常规热解，热辅助水解和甲基化技术与GC-MS串联，以及经典的湿化学法（甲氧基，总羟基和酚羟基，衍生化后进行还原裂解-DFRC）。分离的木质素中β-O-4键的含量与MWL中的相似，并且它们的比例随提取时间的延长而降低。分离的木质素的氧化和总羟基含量随提取时间的增加而显着增加。木质素结构在热水提取过程中发生缩合和脱甲基反应。有人提出在分离的木质素中诱导新的苯基香豆素亚结构。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号