作为固体催化剂的h-MoO,α-MoO和β-MoO相混合物的协同作用,以获得甲基酸
Gabrielle Sophie Medeiros Leão1, Marcos Daniel Silva Ribeiro1, Rubens Lucas de Freitas Filho2
1Departamento de Química, Meio Ambiente e Alimentos (DQA), Grupo de Recursos Energéticos e Nanomateriais (GREEN Group), Instituto Federal de Educação, Ciência e Tecnologia do Amazonas, Campus Manaus Centro, Manaus 69020-120, AM, Brazil.
这项研究用不同度的酸合成了氧化 (MoO3) 催化剂,表明更高度的催化剂对油酸转化具有更高的催化活性. 优化的MoO3_10催化剂表现出极好的性能和可重复使用性.
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.
- 纳米技术 纳米技术
背景情况:
- 实验条件显著影响半导体特性.
- 氧化 (MoO3) 合成需要精确控制酸度等参数.
研究的目的:
- 通过水热法合成氧化物 (MoO3),使用不同度的酸.
- 描述合成MoO3样本的结构,形态和化学特性.
- 评估MoO3在油酸转化为甲基酸盐中的催化性能.
主要方法:
- 在160°C进行6小时的水热合成MoO3,酸度变化 (0.6-2.10 mol L-1).
- 使用X射线衍射 (XRD),拉曼光谱,FTIR和X射线光电子光谱 (XPS) 的结构特征.
- 通过扫描电子显微镜 (SEM) 的形态分析和油酸转化中的催化评估.
主要成果:
- 纯六边形MoO3 (h-MoO3) 在0.6mol L-1酸下得到.
- 较高的度 (1.10-2.10 mol L-1) 导致六边形,正角形和单形MoO3相混合.
- 在MoO3_10样本 (10毫升酸) 中,具有最高的催化转化率 (97.2%) 和优异的可重复使用性 (>9个循环后85%).
- SEM图像证实了六角形和棒形的微晶体,与相位组成和催化活性相关.
结论:
- 3的催化性能严重依赖于合成过程中的酸度.
- 在MoO3_10样本中,六角形MoO3相和正角形MoO3相之间的协同效应增强了催化活性.
- 优化的MoO3_10催化剂由于其高效率和稳定性,是转化油酸的有希望的异质催化剂.
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