高循环聚乙烯二甲酸废物通过光变:Pt共催化剂的双功能
Xiaochi Han1, Ming Jiang1, Huaxing Li2
1School of Chemical Engineering, Sichuan University, No. 24 South Section 1, Yihuan Road, Chengdu 610065, PR China.
Journal of colloid and interface science
|March 24, 2024
概括
这项研究通过使用装饰的二氧化纳米管来增强塑料回收,用于将聚乙烯二甲 (PET) 废弃物光重塑成有价值的化学品和燃料. 催化剂的原子设计优化了PET上循环效率.
科学领域:
- 材料科学 材料科学 材料科学
- 催化剂是一种催化剂.
- 环境化学环境化学
背景情况:
- 光电改造 (PR) 提供了一种可持续的路径,用于回收聚乙烯二甲 (PET) 废物.
- 同时生产有价值的氧化产品和高纯度仍然是一个挑战.
- 贵金属催化剂对于提高PR反应效率至关重要.
研究的目的:
- 研究单个Pt原子 (Pt1/TiO2) 和Pt纳米粒子 (PtNPs/TiO2) 作为PET废物的光变化中的共催化剂的有效性.
- 分析由乙烯糖醇 (EG) 和演化率衍生的氧化产品.
- 阐明Pt原子结构在控制反应路径和产品选择性的作用.
主要方法:
- 用单个Pt原子 (Pt1/TiO2) 和Pt纳米粒子 (PtNPs/TiO2) 装饰的TiO2纳米管的合成.
- 在可见光照射下对乙烯基醇 (水解PET产品) 进行光变.
- 使用气相色谱和其他技术分析液相氧化产物和的演变.
- 密度功能理论 (DFT) 的计算,以了解反应机制和吸附行为.
- 预处理的PET性溶液的酸性化,用于分离甲酸.
主要成果:
- Pt1/TiO2促进了EG氧化成甘素,甘酸盐或乳酸盐,其气演化率 (r H2) 为51.8μmol·h−1·gcat−1,比单独的TiO2高30倍.
- PtNPs/TiO2 实现了 219.1 μmol·h−1·gcat−1 的更高的进化率,但仅产生了乙酸作为氧化产物.
- DFT计算表明,PtNP通过Schottky结有利于的演化,而Pt1/TiO2促进EG的双酸吸附,影响氧化产品的分布.
- 通过PET溶液的酸化,可以获得纯净的甲基乙烯酸 (PTA),这可能会提高反应效率.
结论:
- 在PR反应中的双功能性涉及H2演变的电子转移调解和分子吸附的反应部位.
- 氧化反应由吸附-脱附动态控制,而还原反应则取决于电子转移.
- 原子级催化剂设计和适当的废物预处理是优化PET上循环过程的关键.
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