在低温下,CO2促进了聚烯塑料的高循环转化为芳香化合物
Yi Ding1, Shuchi Zhang1,2, Cheng Liu1,2
1State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
National science review
|April 25, 2024
概括
这项研究提出了一种新方法,用于将塑料废弃物再循环转化为宝贵的芳香物,如,和 (BTX),使用低于300°C的二氧化碳 (CO2). 该过程有效地将塑料和温室气体转化为有用的碳资源.
科学领域:
- 化学工程是化学工程的重要组成部分.
- 材料科学 材料科学 材料科学
- 环境科学 环境科学
背景情况:
- 塑料废物和二氧化碳 (CO2) 是全球环境面临的重大挑战.
- 目前用于塑料上循环的方法,如热解和水力破解,通常需要高温,并产生有限量的有价值的芳香物.
- 催化的一步上循环到,和 (BTX) 等芳香化合物受到高温 (>500°C) 和低产量的限制.
研究的目的:
- 开发一种新的低温催化工艺,用于将废弃的聚烯再循环转化为附加值的芳香化合物.
- 在塑料上循环过程中利用二氧化碳 (CO2) 作为反应剂.
- 为了提高芳香物的产量,并将二氧化碳纳入最终产品.
主要方法:
- 开发一种双功能Pt/MnO(x) - ZSM-5催化剂.
- 在低于300°C的温度下,CO2促进的聚烯的催化上循环.
- 同位素实验,以追踪二氧化碳融入芳香制品中的情况.
主要成果:
- 该过程成功地将多聚烯循环转化为300°C以下的芳化合物.
- 每公斤聚乙烯的产量为0.63公斤芳香物,BTX占60%.
- 每1.0公斤聚乙烯消耗了0.2公斤的二氧化碳,90%的二氧化碳被纳入了芳香物中.
结论:
- 开发的Pt/MnO(x) -ZSM-5催化剂和CO2促进的工艺使塑料废料在低温下有效地回收成芳香物.
- 这种方法为同时解决塑料废弃物和二氧化碳排放提供了一个有希望的策略.
- 该过程将塑料废物和温室气体二氧化碳转化为有价值的碳资源.
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