从复杂的柔性聚氨泡中回收多种聚醇等级,通过与甲胺的脱聚合.
Zoë De Herdt1, Muhammad Adeel2, Lukasz Pazdur1
1Faculty of Applied Engineering, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerpen, Belgium.
这项研究引入了一种新的化学回收方法,用于使用氨酸 (PU) 泡的氨酸 (DEA),通过高效的三相分离,实现高回收率的有价值的芳香胺,如甲基氨酸 (MDA).
科学领域:
- 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.
- 聚合物化学 聚合物化学
背景情况:
- 由于复杂的配方,聚氨 (PU) 泡的化学回收面临着挑战,导致有价值产品的产量较低.
- 现有的方法与多聚醇系统相斗争,限制了芳胺的回收.
研究的目的:
- 开发一种用于PU泡的新型化学脱聚合方法,以提高芳香胺的回收.
- 为了优化反应条件以实现高效的三相分离,并最大限度地提高产品产量.
主要方法:
- 使用二甲醇胺 (DEA) 研究了PU泡的化学脱聚合.
- 评估反应参数:温度,时间和DEA:PU比.
- 分析分离的阶段,以确定组件分布和产品纯度.
- 将该方法应用于各种PU泡类型,包括多重聚合物的MDI和TDI型泡.
主要成果:
- 确定了最佳条件 (240°C,30分钟,DEA:PU 2:1) 以实现清晰的三相分离.
- 从PU泡中恢复了89%的甲基氨酸 (MDA).
- 多聚醇在顶部和中间阶段被回收,而MDA和DEA则在底部阶段被集中.
- 在基于MDI和TDI的复杂泡上证明了该方法的多功能性,最多有五种多聚合物.
结论:
- 以DEA为媒介的脱聚合为复杂PU泡的化学回收提供了一条有效的途径.
- 氨解是主要的反应途径,尿素中间体分解为芳香胺.
- 预测室温测试可靠地表明了三相分离的可行性.
- 类胺,如2-氨基乙醇,也可以促进三相分离,突出了更广泛应用的潜力.
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