在单一催化剂颗粒水平上发生聚烯裂变的运输限制
Sebastian Rejman1, Ina Vollmer1, Maximilian J Werny1
1Inorganic Chemistry and Catalysis, Institute for Sustainable and Circular Chemistry, Debye Institute for Nanomaterial Science, Department of Chemistry, Utrecht University Universiteitsweg 99 3584 CG Utrecht The Netherlands i.vollmer@uu.nl b.m.weckhuysen@uu.nl.
Chemical science
|September 29, 2023
概括
聚烯 (PP) 的催化裂变受到高分子量聚合物的高粘度的阻碍,限制了催化剂的访问和效率. 建议进行预处理以降低粘度,以有效地回收化学品.
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
- 催化剂是一种催化剂.
背景情况:
- 催化裂变通过化学回收聚烯,将其转化为有价值的碳化合物,如油和芳香化合物.
- 传统的裂变催化剂是针对液体或气体原料而优化,而不是大型聚合物分子.
- 聚聚烯具有高融粘度,对催化剂性能构成质量运输挑战.
研究的目的:
- 调查聚烯 (PP) 催化裂变中的大规模运输限制.
- 了解聚合物分子量 (Mw) 对裂变效率的影响.
- 评估催化剂可访问性在多烯转化中的作用.
主要方法:
- 用不同分子量和不同孔径的催化剂的PP进行热重量测试实验.
- 在现场光学显微镜和电子显微镜以分析微和纳米尺度的催化剂聚合物复合材料.
- 聚合物融粘度与催化剂可访问性和裂变性能的相关性.
主要成果:
- 低Mw PP在275°C以下有效破裂,而高Mw PP则需要150°C以上的温度.
- 高Mw PP的高粘度严重限制了催化剂-聚合物接触和进入内部催化剂孔的机会.
- 内部催化剂的活性部位由于扩散不良而未充分利用高Mw聚合物.
- 当使用低Mw模型聚合物时,催化剂活性可能会被高估.
结论:
- 大众运输的局限性,主要是由于高融粘度,显著影响了聚烯烯的催化裂变.
- 聚合物分子重量是决定裂解效率和催化剂利用率的关键因素.
- 通过催化裂变进行有效的化学回收,可能需要进行预处理以降低聚烯融体粘度.
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