低压氧化物和二氧化碳环开放共聚化催化剂的量化 CO2 插入平衡
Katharina H S Eisenhardt1, Francesca Fiorentini1, Wouter Lindeboom1
1Department Chemistry, University of Oxford, Chemistry Research Laboratory, 12 Mansfield Road, Oxford OX1 3TA, U.K.
Journal of the American Chemical Society
|April 8, 2024
概括
新的-催化剂即使在低CO2压力下也能有效地进行二氧化碳 (CO2) 和氧化物 (PO) 的环开合聚合. 这项研究首次量化了二氧化碳平衡常数,并制定了统一的速率定律.
科学领域:
- 催化剂
- 聚合物化学
- 绿色化学
背景情况:
- 二氧化碳 (CO2) 和环氧化物的环开合聚合 (ROCOP) 对于可持续的聚合物生产至关重要.
- 现有的催化剂通常需要高的二氧化碳压力,这限制了它们的实际应用.
- 开发高效的低二氧化碳压力条件的催化剂是非常理想的.
研究的目的:
- 开发和评估用于CO2和氧化物 (PO) ROCOP的新型Co (III) M (I) 异核催化剂.
- 在低CO2压力条件下研究催化剂性能.
- 建立一个统一的速率定律并量化反应的二氧化碳平衡常数.
主要方法:
- 一系列Co (III) M (I) 异质核催化剂的合成和表征.
- 在不同CO2压力下对CO2和PO的ROCOP的活性和选择性测试.
- 动力学研究以确定速度规律和平衡常数.
主要成果:
- 该复合物表现出优异的活性 (TOF=1728h-1) 和选择性 (>90%的聚合物,>99%的CO2合并).
- 在低二氧化碳压力 (< 10 bar) 中观察到高效率.
- 首次量化了二氧化碳平衡常数 (Keq = 1.27 M-1),并通过文献数据推导和验证了统一的速率定律.
结论:
- 对于CO2/PO ROCOP,特别是在低CO2压力下,异构核催化剂的效率非常高.
- 这项研究提供了对反应机制的基本见解,并建立了预测速率定律.
- 这项工作有助于开发高效的聚合物合成中二氧化碳利用的催化系统.
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