一种可重复使用,耐杂质和不含贵金属的催化剂,用于废弃聚烯烯的水裂化
Zetian Qiu1, Siyu Lin1, Zhuo Chen1
1School of Physical Science and Technology (SPST), ShanghaiTech University, Shanghai 201210, People's Republic of China.
Science advances
|June 21, 2023
概括
这项研究介绍了一种可重复使用的,无金属的催化剂,用于废塑料的一步化学回收. 新型催化剂在温和条件下有效地将不纯的聚烯转化为有价值的液态基.
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.
- 可持续化学 可持续化学
背景情况:
- 聚烯的化学回收面临着杂质和催化剂兼容性的挑战.
- 现有的方法通常需要对塑料废物进行预处理,这限制了实际应用.
- 开发强大的,耐杂质的催化剂对于高效的塑料价值化至关重要.
研究的目的:
- 开发一种可重复使用的,无贵金属的,耐杂质的催化剂,用于直接化聚烯.
- 为了实现低纯度和混合塑料废物的有效转化为增值液态基.
- 为了证明用于塑料回收的温和水力转化条件的可行性.
主要方法:
- 一种双功能催化剂,硫化-β-β (MoS2-β-β),被合成和表征.
- 在温和条件下 (≤250°C,20-30 bar H2) 对各种聚烯进行了水力转化反应.
- 用不同类型的聚烯评估了催化剂的性能,包括受污染和混合聚合物样本.
主要成果:
- 在温和条件下从聚烯中获得96%的分支液态基的产量.
- 在广泛的聚烯中证明了催化剂的有效性,包括含杂质的消费后废物.
- 即使在低至180°C的温度下,也观察到成功的转化.
- 催化剂显示可重复使用性和对常见污染物和添加剂的耐受性.
结论:
- MoS2-Hbeta催化剂为不纯聚烯的直接化学回收提供了一个有前途的解决方案.
- 在温和条件下的水力转化为利用废塑料作为碳原料提供了一个可行的途径.
- 这种方法最大限度地减少了预处理步骤,提高了塑料回收的经济和环境可行性.
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