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通过化脱聚合和化转化PET转化为1,4-环二甲醇和p-xylen的反应机制

Xiaosong Luo¹, Qibin Li¹

¹Key Laboratory of Low-grade Energy Utilization Technologies and Systems, Ministry of Education, School of Energy and Power Engineering, Chongqing University, Chongqing, 400044, China.

Journal of environmental management

|February 3, 2026

概括

这项研究提出了一种新的协同方法,用于将废弃聚乙烯二甲 (PET) 循环升级为1,4-环二甲醇 (CHDM) 和p-xylen (PX) 等有价值的化学物质. 该过程同时从废物中再生化,为塑料和化废物利用提供双重效益的途径.

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
环境化学环境化学

背景情况:

将聚乙烯二甲 (PET) 等塑料再循环转化为高价值产品对于可持续发展至关重要.
在塑料上循环过程中,从含有的废物中同时再生化物 (HF,HCl,HBr),提供了双重效益的机会.
这种双重过程的进化行为和分解机制仍然不清楚,这带来了重大挑战.

研究的目的:

阐明涉及化辅助脱聚合和化的双联方法,用于将废弃PET转化为1,4-环二甲醇 (CHDM) 和p-xylen (PX).
了解反应机制,并确定速率决定的步骤.
评估水对化阶段和产品整体产量的影响.

主要方法:

采用理论和实验方法来研究PET上循环过程.
使用酸来使PET脱聚变为中间载体化合物.
研究了中间体的后续化,以再生化并产生CHDM和PX.

主要成果:

PET转化为CHDM和PX发生在两个阶段:脱聚合和化.
已识别的中间化合物:1,4-二二化物,二甲化物和1,4-二二化物.
已确定脱聚合的速率决定性步骤障碍 (大约. 153 kJ/mol,132 kJ/mol,123 kJ/mol) 的情况,则表示
在化过程中在现场再生HF,HCl和HBr.
观察到水在化过程中抑制了PX和CHDM的形成.

结论:

开发的合方法可以有效控制含有素的废物,降低HF的腐蚀性风险.
通过这种新的战略,实现了能源消耗的减少.
为利用聚废塑料和化废料的资源提供了一个有前途的方法.

关键词:

1,4-循环和甲基甲醇的使用.对于P-烯来说,这是一个很好的方法.聚乙烯四甲酸是一种聚乙烯四甲酸.反应机制的反应机制

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