使用在氧气大气中循环的微滴氧化到氧化
Lian Xue1, Weida Chen1, Peng Zheng1
1Key Laboratory of Mesoscopic Chemistry of MOE, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, PR China.
Journal of the American Chemical Society
|September 20, 2024
概括
在没有催化剂的情况下,水微滴加速 styrene 的氧化. 这种循环喷方法显著提高了反应速度和产品度,显示了工业化工合成的潜力.
科学领域:
- 化学工程
- 物理化学
- 材料科学
背景情况:
- 水微滴具有独特的界面特性,促进自发化学反应.
- 与散装溶液相比,这些界面效应可以显著提高反应速率.
- 利用微滴化学为有效的化学合成提供了新的途径.
研究的目的:
- 在空气中的水微滴中,研究 styrene (SY) 到 styrene oxide (SO) 的氧化.
- 通过循环喷雾来探索无催化氧化机制并提高反应效率.
- 评估微滴技术在大型化学生产中的潜力.
主要方法:
- 循环喷含有烯的水,形成微滴 (平均直径6.7μm).
- 在有氧条件下在微滴中氧化.
- 密度函数理论 (DFT) 计算以阐明反应机制.
- 使用超声波进一步增强反应.
主要成果:
- 在没有催化剂的微滴中氧化成烯氧化物,检测到4. 2%的SY转化和3.1 mM的SO.
- 在相同条件下,在散装溶液中没有观察到SY氧化产物.
- 与传统方法相比,微滴反应使氧化产品度增加了1000倍.
- 超声波进一步增强了该过程,达到7.0%的SY转换和5.2mM的SO.
- 在滴滴界面提出了一种双路过氧化机制,并得到了DFT的确认.
结论:
- 水微滴提供了一个独特的环境,可以有效地无催化剂氧化.
- 循环喷方法大大提高了反应速率和产品产量.
- 涉及过氧化的拟议界面氧化机制得到实验和计算数据的支持.
- 微滴技术显示出可扩展和可持续化工制造的巨大潜力.
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