Deactivation behaviors of gold catalysts in the liquid-phase oxidation of monoethanolamine to glycine were revealed. Properties of the catalysts including Au loading, the valence distribution, and particle size of Au nanoparticles before and after batch reactions were investigated by BET, ICP, XRD, XPS, and TEM. It was found that the main reason for the catalytic deactivation was aggregation of Au nanoparticles. The Au aggregation mechanism of oxidative dissolution-reductive deposition in the reaction was proposed and this mechanism could help to understand the common aggregation of Au nanoparticles in the liquid-phase oxidation of alcohols.

中文翻译：

---

负载金纳米颗粒在单乙醇胺氧化成甘氨酸中的失活行为和聚集机理

揭示了金催化剂在单乙醇胺液相氧化成甘氨酸中的失活行为。通过BET，ICP，XRD，XPS和TEM研究了间歇反应前后Au纳米粒子的载金量，化合价分布和粒径等催化剂性质。发现催化失活的主要原因是金纳米颗粒的聚集。提出了反应中氧化溶解-还原沉积的Au聚集机理，该机理可帮助理解Au纳米颗粒在醇液相氧化中的常见聚集。