糖醇在Cu-Fe-Al基氧化物上的催化脱水:了解整个反应中的活性位点的变化
Felipe Fernandes Barbosa1, João Edson Tavares2, Anderson Dos Reis Albuquerque2
1Laboratório de Peneiras Moleculares, Instituto de Química, Universidade Federal do Rio Grande do Norte 59078-970 Natal RN Brazil tiago.braga@ufrn.br +55-84-3342-2323.
RSC advances
|October 26, 2023
概括
这项研究探讨了Fe,Al和Cu基氧化物对糖转化为乙醇的作用. 优化的催化剂实现了60%的转化率和92%的乙醇选择性,证明了高效和可重复使用的催化性能.
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.
- 化学工程是化学工程的重要组成部分.
背景情况:
- 糖转化为增值化学品对于生物炼油厂至关重要.
- 开发高效和有选择性的催化剂从糖生产乙醇是一个持续的挑战.
研究的目的:
- 研究Fe,Al和Cu基氧化物催化剂的合成和表征,用于将甘油转化为乙醇.
- 评估这些氧化物的催化性能,稳定性和可重复使用性.
- 了解易斯酸度和活性位点在乙醇和焦炭形成中的作用.
主要方法:
- 基于Fe,Al和Cu的氧化物的合成和表征,使用XRD,拉曼,莫斯巴乌尔,NMR,XPS,FTIR,TPR,N2物理吸收,SEM和TEM等技术.
- 在优化条件下对糖转化为乙醇的催化试验.
- 催化剂的回收和重新激活测试.
- 使用DFT进行理论计算研究,分析表面电荷分布和活性点协同作用.
主要成果:
- 催化剂呈现出具有高相散和微-半孔结构的纳米颗粒.
- 优化的催化剂实现了60%的糖醇转化和92%的乙醇选择性,其中17%的焦炭形成.
- 催化剂表现出良好的可重复使用性,在四个周期和重新激活后保持显著的活性.
结论:
- 基于Fe,Al和Cu的氧化物是糖转化为乙醇的有效催化剂.
- Cu0/Cu+活性位点和易斯酸位点 (Fe3+,Al3+) 之间的协同作用是高乙醇选择性的关键.
- 由于其稳定性和可重复使用性,催化剂对工业应用具有前景.
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