关于电子密度特征集团在煤炭热解过程中对变化的影响的研究
Hai Zhang1, Xin Wang1, Chuanjin Zhao1
1Institute of Thermal Energy Engineering, School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China.
The journal of physical chemistry. A
|May 12, 2025
概括
功能组显著影响煤炭热解和迁移. 电子捐赠小组增强热解,而电子吸收小组抑制它,由DFT计算和实验证实.
科学领域:
- 化学工程是化学工程的重要组成部分.
- 计算化学的计算化学
- 材料科学 材料科学 材料科学
背景情况:
- 煤炭热解对于能源回收和化学品生产至关重要.
- 了解热解过程中的迁移是控制排放和产品产量的关键.
- 功能群对煤炭热解动学的影响仍然是一个活跃的研究领域.
研究的目的:
- 阐明功能组在煤炭热解过程中的迁移中的作用.
- 调查电子捐赠组 (EDG) 和电子吸收组 (EWG) 对热解路径的影响.
- 开发煤炭热解行为的预测模型.
主要方法:
- 密度函数理论 (DFT) 计算以建模反应路径和能量障碍.
- 支持向量回归 (SVR) 建模结合RDKit描述器进行预测.
- 热重力测量-里埃变换红外光谱 (TG-FTIR) 实验进行验证.
主要成果:
- 电子捐赠组 (EDG) 增强了煤炭热解和HCN的产生.
- 电子提取组 (EWG) 抑制了煤炭热解.
- DFT和SVR模型准确地预测激活和反应能量,突出显示S型描述器的重要性.
- 实验验证证了EDG的加速作用和EWG的减速作用.
结论:
- 功能组在煤炭热解过程中调节迁移方面发挥着至关重要的作用.
- 通过降低能量障碍,EDG加速了热解,而EWG则减缓了热解.
- 开发的DFT-SVR方法为预测煤炭热解行为提供了一个强大的框架,并为流程优化提供了洞察力.
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