选择性氧化甲到甲醇通过现场合成H2O2
Fenglou Ni1, Thomas Richards1, Louise R Smith1
1Max Planck-Cardiff Centre on the Fundamentals of Heterogeneous Catalysis FUNCAT, Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff CF10 3AT, United Kingdom.
ACS organic & inorganic Au
|August 7, 2023
概括
金催化剂使用过氧化有效地将甲转化为甲醇. 将黄金与合金增强了由黄金驱动的催化活性.
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
- 化学工程是化学工程的重要组成部分.
背景情况:
- 将甲选择性氧化成甲醇对于将天然气转化为有价值的化学物质至关重要.
- 过氧化 (H2O2) 是一种环保的氧化剂,但其有效的现场生成和利用仍然具有挑战性.
- 由于其独特的特性,ZSM-5支持的催化剂具有提高催化性能的潜力.
研究的目的:
- 调查ZSM-5支持的金双金属催化剂 (AuPd) 对于选择性氧化甲到甲醇的有效性.
- 探索元素组成和合金在催化剂性能中的作用.
- 了解过氧化合成/降解和甲氧化活动之间的关系.
主要方法:
- 使用沉积-沉协议制备ZSM-5支持的不同组成的AuPd催化剂.
- 使用现场生成的H2O2.2,评估甲选择性氧化的催化性能.
- 在理想条件下对H2O2直接合成和降解的补充研究.
主要成果:
- 在ZSM-5支持的催化剂中与黄金合金,与单金属催化剂相比,显著改善了甲氧化为甲醇的过程.
- 催化剂的有效性与H2O2生产或降解的速度没有直接相关.
- 黄金已知的促进活性氧物种 (ROS) 释放的能力被认为是提高双金属催化剂性能的关键因素.
结论:
- 支持ZSM-5的AuPd双金属催化剂对于选择性甲转化为甲醇的氧化非常有效.
- 这种增强的性能归因于黄金的协同效应,可能是通过促进活性氧物种,而不是仅仅是H2O2生产率.
- 这项研究提供了对设计高效的催化剂的见解,以提高甲的价值.
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