从刚性聚氨泡中通过氨解回收聚醇和芳香氨基
Lander Van Belleghem1, Robin Dirix1, Rodrigo de Oliveira Silva1
1Centre For Membrane Separations, Adsorption, Catalysis and Spectroscopy for Sustainable Solutions (cMACS), Celestijnenlaan 200F, Post box 2454, 3001 Leuven, Belgium.
JACS Au
|August 1, 2025
概括
氨解有效地将刚性聚氨 (PU) 泡回收成有价值的芳香胺和聚醇. 这种化学回收方法提供了高生产率和高效的回收,解决了当前PU泡回收工艺的局限性.
科学领域:
- 聚合物化学 聚合物化学
- 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:
- 聚氨 (PU) 是全球重要的塑料,但其化学回收是具有挑战性的,特别是对于刚性泡.
- 目前的回收方法往往忽略了芳香化合物,并且回收材料的替代率很低.
- 由于其复杂的结构,回收刚性PU泡比柔性泡更困难.
研究的目的:
- 为刚性PU泡开发一种有效的化学回收方法.
- 从刚性PU废物中高效地产生芳香胺和多.
- 为了使在过程中使用的过量的氨容易回收.
主要方法:
- 使用氨的氨解来去聚合刚性PU泡.
- 对刚性PU材料进行定量1HNMR分析的开发.
- 动力学研究和固态NMR分析,以了解脱聚合机制.
主要成果:
- 氨解实现了高体积生产率 (高达300g·L−1·h−1),超过了现有的刚性PU回收工艺.
- 确定了脱聚合过程中的键裂序:尿素 > 碳酸盐 > 异酸盐.
- 证明了氨解混合物的高效分离到纯聚和芳香氨基分离物.
结论:
- 氨溶解是回收刚性PU泡的最佳和具有工业意义的方法.
- 该方法通过氨的键破坏,有效地分解具有挑战性的PU硬片段.
- 该工艺显示出高的孤立产量有价值的异酸衍生物和聚醇,适用于退役废物.
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