氧化酸化为甘油酸:向稳定和选择性的催化剂发展
Eric Schuler1, Lars Grooten1, Mohanreddy Kasireddy2
1Van 't Hoff Institute for Molecular Sciences, University of Amsterdam, Science Park 904, 1090 GD Amsterdam, The Netherlands.
ACS omega
|June 9, 2025
概括
研究人员开发了高效的-锡催化剂,用于将酸转化为甘油酸,这是迈向可持续聚合物和循环经济的关键一步. 这个过程利用了二氧化碳和生物质,减少了对化石燃料的依赖.
科学领域:
- 催化剂是一种催化剂.
- 绿色化学 绿色化学
- 材料科学 材料科学 材料科学
背景情况:
- 转向循环经济对于缓解气候变化和生物多样性丧失至关重要.
- 将化石聚合物替换为由二氧化碳或生物质获得的可持续替代品至关重要.
- 甘油酸是聚合物的有价值单体,可以通过选择性化从酸中生产出来.
研究的目的:
- 开发高度选择性和稳定的催化剂,用于直接化氧酸到甘油酸.
- 优化催化剂成分,包括-锡比率和支,以提高性能.
- 研究催化剂失活机制,提高长期稳定性.
主要方法:
- 合成和表征双金属 (Ru-Sn) 和三金属 (Ru-Sn-Pt) 催化剂.
- 在不同条件下 (压力,温度) 进行氧化酸化的批量和流量反应器研究.
- 在酸性介质中分析反应产物 (甘油酸,酸) 和催化剂稳定性.
主要成果:
- 在批量反应堆中达到95%的甘氨酸产量,在流动反应堆中达到100%的产量.
- 保持高选择性 (>90%) 糖醇酸和低副产品形成 (<5%的酸).
- 鉴定了与不足的Ru/Sn金属还原相关的催化剂失活;化物存在会对稳定性产生负面影响.
- 添加显著提高了催化剂的稳定性,在多次使用时,活性损失仅为9%.
结论:
- 开发了基于Ru-Sn的高效和稳定的催化剂,用于直接将酸转化为甘油酸.
- 证明了利用二氧化碳和生物质衍生氧化酸作为可持续聚合物的单体的潜力.
- 优化的催化系统为塑料和化学品提供了通往循环经济的可行途径.
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