用红外和核磁共振光谱学对热带石复合材料的评估
Francesco Dalena1, Eddy Dib1, Barbara Onida2
1ENSICAEN, UNICAEN, CNRS, Laboratoire Catalyse et Spectrochimie, Normandie University, 14000 Caen, France.
Molecules (Basel, Switzerland)
|September 28, 2024
概括
在ZSM-5石上,石-1的生长因孔隙占用而有所不同. 与含有有机结构定向剂的复合材料相比,带有空 ZSM-5 孔的复合材料表现出改变的表面积和减少的酸度.
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.
- 频谱学是一种光谱学.
背景情况:
- 岩复合材料,如在ZSM-5上生长的岩-1,在催化过程中至关重要.
- 了解这些复合材料的合成和特性是优化其性能的关键.
- 在合成过程中有机结构指导剂 (OSDA) 的存在可以影响焦化的结构和特性.
研究的目的:
- 为了评估Silicalite-1/ZSM-5热化合物的数量,强度和酸度.
- 为了研究有机结构指导剂 (OSDA) 在-1生长期间在ZSM-5通道中存在的影响.
- 为了比较ZSM-5核心中用和没有OSDA合成的复合材料的性能.
主要方法:
- 在有或没有OSDA (H_ZSM-5_Sil1和TPA_ZSM-5_Sil1) 的ZSM-5 (P_ZSM-5) 上生长的化石-1的合成.
- 使用红外 (IR) 光谱学进行表征.
- 使用固态核磁共振 (NMR) 光谱 (29Si和1H NMR) 的分析.
主要成果:
- 根据ZSM-5孔隙是否空 (H_ZSM-5_Sil1) 或被OSDA (TPA_ZSM-5_Sil1) 占用,石-1的生长有所不同.
- H_ZSM-5_Sil1显示微孔面积减少和外部表面积增加;TPA_ZSM-5_Sil1的特性与父P_ZSM-5相似.
- TPA_ZSM-5_Sil1保留了酸性部位,而H_ZSM-5_Sil1显示了布伦斯特德酸性部位的显著减少.
结论:
- 合成条件,特别是ZSM-5中OSDA的存在或不存在,极大地影响了所得到的烯酸复合物的质地特性和酸度.
- 在ZSM-5上,石-1的生长对核心石通道内模板的存在敏感.
- 光谱法 (IR和NMR) 有效地区分了这些热化合物的结构和酸性特征.
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