对化环氧树脂的催化脱机制进行量子化学研究
Yufeng Wu1, Zhongxun Tian1, Bin Li1
1Institute of Circular Economy, Beijing University of Technology, Beijing 100124, PR China; Faculty of Materials and Manufacturing, Beijing University of Technology, Beijing 100124, PR China.
Journal of hazardous materials
|December 23, 2023
概括
这项研究使用密度功能理论来探索用铁 (Fe) 和铜 (Cu) 催化剂和电场 (EF) 进行化环氧树脂 (BER) 脱. 结果显示,EF和催化剂显著降低了C-Br键能量,有助于除.
科学领域:
- 材料科学 材料科学 材料科学
- 催化剂是一种催化剂.
- 计算化学计算化学
背景情况:
- 化环氧树脂 (BER) 由于其含量而带来环境挑战.
- 有效的除方法对于BER的回收和处置至关重要.
- 了解催化机制是制定有效的除策略的关键.
研究的目的:
- 用铁 (Fe) 和铜 (Cu) 催化剂研究BER的催化除机制.
- 探索外部电场 (EF) 对除过程的影响.
- 阐明电子转移,极化和C-Br键裂变中的结构变化的作用.
主要方法:
- 用密度函数理论 (DFT) 的计算来建模反应机制.
- 分析了Fe,Cu催化剂和EF对C-Br键解离能量 (BDE) 的影响.
- 进行了实验验证,以确认关于EF效应的计算发现.
主要成果:
- 与未催化状态 (312.27 kJ/mol) 相比,Fe (114.47 kJ/mol) 和Cu (94.85 kJ/mol) 催化剂显著降低了C-Br键解离能量 (BDE).
- 应用的EF,特别是与C-Br键平行,通过改变静电电位和增加分子极性 (高达50.19%) 来降低BDE.
- 铁和促进了电子转移,增加了极性并进一步减少了BDE,而EF提高了整体除效率,尽管它阻碍了低温的催化.
结论:
- 两种Fe和Cu催化剂,以及应用的EF,通过削弱C-Br键,有效促进BER的脱.
- 催化和EF的联合作用涉及复杂的电子和结构修改,促进C-Br键裂变.
- 实验结果证实了EF提高除效率的能力,突出了其在BERs处理策略中的潜力.
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