在亚临界水自解过程中,裸麦茎中的素的溶解和结构变化
Long Jiang1, Yanchen Zhu1, Jiahui Wei1
1Jiangsu Co-Innovation Center for Efficient Processing and Utilization of Forest Resources, Jiangsu Provincial Key Lab of Pulp and Paper Science and Technology, Nanjing Forestry University, Nanjing 210037, China.
International journal of biological macromolecules
|March 16, 2024
概括
裸麦茎的亚临界水自解优先水解半纤维素,产生改变素结构的酸. 低于190°C的条件有利于青素的降解,而更高的温度则促进了青素的凝结.
科学领域:
- 生物质加工生物质的加工.
- 电的化学性质
- 绿色化学是一种绿色化学.
背景情况:
- 亚临界水自水解是一种有前途的生物质价值化方法.
- 了解这些条件下的素的行为对于高效的生物质转化至关重要.
研究的目的:
- 为了研究在亚临界水自解过程中裸麦茎中素的溶解和结构变化.
- 阐明温度和压力对木质素降解和凝结的影响.
主要方法:
- 裸露的麦茎使用亚临界水自水解在170-210°C的温度和0.68-1.85MPa的压力下进行处理.
- 对水解残留物和溶液进行了对木质素结构变化的分析,包括键裂和凝结.
主要成果:
- 半纤维素水解产生有机酸,使系统酸化.
- 包括β-O-4键裂解在内的素降解在190°C和1.22MPa以下占主导地位,达到47.8%的去除.
- 在高于190°C的温度和高于1.22 MPa的压力下,素凝结反应增加,与有机酸含量增加相关.
结论:
- 亚临界水自解通过降解和凝结显著影响红素结构.
- 反应条件对素转化的主导途径产生重要影响.
- 这项研究提供了关于生物质加工过程中红素的动态结构演变的关键见解.
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