The role of crystal diversity in understanding mass transfer in nanoporous materials.
The role of crystal diversity in understanding mass transfer in nanoporous materials.
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DOI：
10.1038/nmat4510
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发表时间：
2016-04
期刊：
影响因子：
41.2
通讯作者：
Julien Cousin Saint Remi;Alexander Lauerer;C. Chmelik;I. Vandendael;H. Terryn;G. Baron;J. Denayer
中科院分区：
文献类型：
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作者：
Julien Cousin Saint Remi;Alexander Lauerer;C. Chmelik;I. Vandendael;H. Terryn;G. Baron;J. Denayer
纳米多孔材料在我们的社会中有着广泛的应用：从药物输送到环境友好的催化和分离技术，。这些过程的有效设计关键取决于对传质机理的理解。这通常是通过摄取或释放实验来确定的，该实验是用纳米多孔晶体的组合来进行的，假设所有晶体都是相同的。使用显微成像技术，我们现在表明，即使是明显相同的晶体（即类似的大小和形状的晶体）从同一批次可能会表现出非常不同的吸收率。表面电阻对整体输运电阻的相对贡献随晶体和客体分子而变化。由于这种晶体多样性，常规方法可能无法正确区分不同的传质机制。这种多样性的检测增加了一个重要的新证据，在寻找表面障碍现象的起源。我们的研究进行了与SAPO-34沸石，在甲醇制烯烃（MTO）过程中的关键材料，丙烷-丙烯分离，吸附热转换。
Nanoporous materials find widespread applications in our society: from drug delivery to environmentally friendly catalysis and separation technologies,,,,,. The efficient design of these processes depends crucially on understanding the mass transfer mechanism. This is conventionally determined by uptake or release experiments, carried out with assemblages of nanoporous crystals, assuming all crystals to be identical. Using micro-imaging techniques, we now show that even apparently identical crystals (that is, crystals of similar size and shape) from the same batch may exhibit very different uptake rates. The relative contribution of the surface resistance to the overall transport resistance varied with both the crystal and the guest molecule. As a consequence of this crystal diversity, the conventional approach may not distinguish correctly between the different mass transfer mechanisms. Detection of this diversity adds an important new piece of evidence in the search for the origin of the surface barrier phenomenon. Our investigations were carried out with the zeolite SAPO-34, a key material in the methanol-to-olefins (MTO) process, propane–propene separation,and adsorptive heat transformation.