盐与氨基功能化石墨烯氧化物共同结,作为选择性环氧化过程中有效的异质催化剂
Robabeh Hajian1, Narjes Sadat Mousavi1
1Department of Chemistry, Yazd University Yazd 89195-741 Iran rhajian@yazd.ac.ir +98-353-8210644 +98-353-31232822.
RSC advances
|December 6, 2024
概括
这项研究报告了一种新型的 (iii) 盐 (MnSalop) 催化剂,该催化剂在石墨烯氧化物 (GO·NH2) 上固定,用于高效的烯烯环氧化. 可重复使用的异质催化剂在温和条件下使用过氧化表现出高的选择性和转化.
科学领域:
- 催化剂是一种催化剂.
- 材料科学 材料科学 材料科学
- 有机化学 有机化学
背景情况:
- ) 盐 (MnSalop) 复合物是氧化反应的有效催化剂.
- 在像氧化石墨烯 (GO) 这样的固体支上固定催化剂可以提高它们的稳定性,可重复使用性,并促进分离.
- 在有机合成中,开发绿色和高效的烯酸环氧化催化系统至关重要.
研究的目的:
- 为了合成和描述一种新型异质催化剂,其中包括MnSalop,该催化剂在3-aminopropyltrimethoxysilane修饰的石墨烯氧化物 (GO·NH2) 上固定.
- 评估MnSalop-GO·NH2异质催化剂的催化性能,用于使用过氧化作为绿色氧化剂氧化.
- 在温和反应条件下研究催化剂的稳定性,可重复使用性和效率.
主要方法:
- 在GO·NH2上固定的MnSalop的合成.
- 使用FTIR,DR UV-Vis,FESEM,XRD,元素映射,TGA/DTG,BET和ICP分析对催化剂进行全面的表征.
- 在室温下使用H2O2和NaHCO3作为辅助催化剂,对各种olefins进行催化环氧化.
主要成果:
- 合成和表征MnSalop-GO·NH2催化剂成功,证实了MnSalop复合体和支持的完整性.
- 异质催化剂在烯酸环氧化过程中表现出高效率,对环氧化物具有88-100%的选择性.
- 周转频率 (TOF) 值在40.7至162.8h-1之间,大多数olefins的转化率很高.
- 催化剂表现出很好的可重复使用性,在四个循环后保持催化性能,没有显著的损失.
结论:
- 固定的MnSalop-GO·NH2催化剂是一种高效,选择性和可重复使用的异质系统,用于olefin环氧化.
- 使用H2O2作为绿色氧化剂和温和的反应条件使这种催化系统对环境友好.
- 这种方法为环氧化物合成中的工业应用提供了同质催化剂的有希望的替代方案.
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