在β-MnO2上对5-hydroxymethylfurfural氧化成2,5-furandicarboxylic 酸的氧和表面氧的影响:DFT,微动力学和实验研究
Bunrat Tharat1, Lappawat Ngamwongwan1, Theerada Seehamongkol2
1School of Chemistry, Institute of Science, Suranaree University of Technology, Nakhon Ratchasima, Thailand 30000. suthirak@sut.ac.th.
Nanoscale
|November 15, 2023
概括
在二氧化 (β-MnO2) 上的活性表面氧和基增加了5-基甲基 (HMF) 到2,5-基酸 (FDCA) 的氧化. 这种洞察力提高了生物塑料的催化剂设计.
科学领域:
- 不同质的催化剂.
- 材料科学 材料科学 材料科学
- 绿色化学 绿色化学
背景情况:
- 二氧化 (β-MnO2) 是氧化5-基甲基 (HMF) 到2,5-基酸 (FDCA) 的有希望的催化剂,这是聚乙烯酸 (PEF) 生物塑料的关键单体.
- 了解表面物种的作用,如基 (OH) 组和活性氧,对于优化β-MnO的催化性能至关重要.
研究的目的:
- 阐明表面氧和基物种对由β-MnO2催化的HMF-FDCA氧化反应的影响.
- 确定限制速度的步骤,并提供增强催化活性的策略.
主要方法:
- 密度函数理论 (DFT) 计算以调查反应机制和表面相互作用.
- 微动力学建模以确定氧化和非氧化表面的速度限制步骤.
- 在连续流氧化中使用合成的β-MnO2进行实验验证.
主要成果:
- 发现活性表面氧和OH物种 (来自基或溶剂) 都能促进C-H键断裂和OH插入,增强β-MnO活动.
- 微动力学建模确定了FFCA-to-FDCA和DFF-to-FFCA的步骤,分别为基化和非基化表面的速度限制.
- 使用水和DMSO作为溶剂的实验结果与理论预测一致,在72小时内显示出高HMF转化 (≥99mol%) 和FDCA产量 (85-92mol%).
结论:
- 氧和表面氧物种的存在显著增强了β-MnO2用于HMF氧化的催化活性.
- 考虑这些物种为改善FDCA生产的Mn氧化物和其他金属氧化物催化剂提供了一种新的策略.
- 合成的β-MnO2催化剂显示出高稳定性和持续生产FDCA的活性.
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