通过催化剂控制的光氧化对商用聚乙烯进行化学上循环
1Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States.
Journal of the American Chemical Society
|March 23, 2022
概括
这项研究提出了一种新的方法,用于将聚乙烯 (PS) 转化为有价值的醇产品,主要是酸. 催化剂控制的光氧化降解有效地分解PS,为减少塑料废物提供了有前途的解决方案.
科学领域:
- 化学工程
- 聚合物科学
- 绿色化学
背景情况:
- 塑料污染,尤其是聚乙烯 (PS) 的污染,对环境构成重大挑战.
- 有效地将PS化学上循环转化为有价值的小分子对于可持续的废物管理至关重要.
研究的目的:
- 开发一种由催化剂控制的光氧化降解方法,用于提升聚烯的循环.
- 将聚乙烯转化为焦酸的焦产品.
主要方法:
- 使用铁化物 (FeCl3) 作为催化剂,在白光照射下进行同解裂,以产生基.
- 使用富含氧气的环境来促进降解过程.
- 通过基进行原子抽象的机械路径.
主要成果:
- 实现高分子量聚乙烯 (>90 kg/mol) 的有效降解至<1 kg/mol.
- 产生大量的醇产品,高达23mol%,主要是酸.
- 通过光流工艺证明与含有商业聚烯的填充剂的兼容性和可扩展性.
结论:
- 开发的光氧化降解方法有效地将聚乙烯转化为有价值的基产品.
- 基在通过原子抽象促进聚合物降解方面发挥着关键作用.
- 这一过程显示出在塑料废弃物回收利用中的工业应用潜力.
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