一个机械和动力学研究氧化热分解的decabromodiphenyl以太
Yao Wang1, Jinbao Huang1, Sijia Li1
1School of Physics and Mechatronic Engineering, Guizhou Minzu University, Guiyang, 550025, China.
Environmental pollution (Barking, Essex : 1987)
|June 16, 2023
概括
甲二乙烯 (BDE-209) 的热分解主要涉及链裂变,产生危险的化化合物. 了解这些氧化途径对于控制BDE-209的有毒排放至关重要.
科学领域:
- 环境化学环境化学
- 计算化学计算化学
- 材料科学 材料科学 材料科学
背景情况:
- 甲二乙烯 (BDE-209) 是一种持久性有机污染物.
- 涉及BDE-209的热工艺会产生危险的副产品.
- 在氧化条件下BDE-209的精确分解机制尚未完全理解.
研究的目的:
- 阐明BDE-209的氧化热分解机制.
- 确定导致危险污染物形成的关键中间体和途径.
- 为控制 BDE-209 排放提供洞察力.
主要方法:
- 密度函数理论 (DFT) 的计算.
- 使用的M06/cc-pVDZ理论水平.
- 对反应路径和能量障碍的分析.
主要成果:
- 无障碍以太链接裂变是主要的初始步骤 (>80%的分支比率).
- 关键的中间体包括pentabromophenyl,pentabromophenoxy和pentabromocyclopentadienyl基.
- 已经确定了八甲化二二氧化, furan 和 octabromonaphthalene 的形成途径.
结论:
- 这项研究阐明了BDE-209.9复杂的氧化热分解过程.
- 具体的基质中间体及其转化是详细的.
- 这些发现为减轻与BDE-209热降解相关的环境风险提供了基础.
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