使用商业塑料添加剂回收消费后废弃物聚乙烯
Sewon Oh1, Hanning Jiang2, Liat H Kugelmass1
1Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14850, United States.
ACS central science
|January 27, 2025
概括
黑色塑料的回收利用可见光和碳黑色素来有效地去聚合成烯单体,现在是可能的. 这种方法使所有彩色聚钢塑料的闭环回收成为可能.
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:
- 光热转化为塑料脱聚合提供了一个有前途的途径,通过光热转化实现化学回收.
- 在光热剂附近局部加热允许选择性塑料降解,这是比散装热解的关键优势.
- 实际的光热剂用于终生塑料回收仍然是一个挑战,限制了广泛采用.
研究的目的:
- 研究聚烯中碳黑色素的使用,作为光热剂,用于高效的塑料去聚合.
- 为了证明可见光驱动的黑色聚钢回收成烯单体的可行性.
- 探索所有彩色聚烯塑料的闭环回收系统的潜力.
主要方法:
- 合成的聚乙烯碳黑复合材料用于模型系统评估.
- 用白色LED灯照射辐射复合材料以诱导脱聚合.
- 在可见光和聚焦太阳辐射下测试未经修改的消费后黑色聚烯样本.
- 研究了含有黑色聚烯的混合聚烯塑料的脱聚合.
主要成果:
- 通过使用LED照射,从合成的聚乙烯碳黑复合材料中获得高达60%的烯单体产量.
- 在没有催化剂或溶剂的情况下,成功地将未经修改的消费后黑色聚乙烯解聚化为 styrene 单体.
- 使用聚焦太阳辐射,在5分钟内观察到高达80%的产量.
- 通过加入少量的黑色聚烯来证明混合聚烯类型的完全脱聚合.
结论:
- 商业黑色塑料中的碳黑作为有效的光热剂,用于使用可见光去聚合聚烯.
- 这种方法提供了一个简单的,无催化剂和无溶剂的方法,用于化学回收聚乙烯.
- 该技术通过利用现有的添加剂为所有彩色聚乙烯塑料铺平了闭环经济的道路.
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