On the Spontaneous Formation of Clathrate Hydrates at Water–Guest Interfaces
On the Spontaneous Formation of Clathrate Hydrates at Water–Guest Interfaces
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DOI：
10.1021/jp211784w
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发表时间：
2012-04
影响因子：
3.7
通讯作者：
L. Boewer;J. Nase;M. Paulus;F. Lehmkühler;S. Tiemeyer;Sebastian Holz;D. Pontoni;M. Tolan
中科院分区：
文献类型：
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作者：
L. Boewer;J. Nase;M. Paulus;F. Lehmkühler;S. Tiemeyer;Sebastian Holz;D. Pontoni;M. Tolan
水合物的形成，即笼状的水-气结构，在工业和研究中都具有极其重要的意义。虽然具有重大意义，但其形成过程迄今尚不完全清楚。我们对水与异丁烷、丙烷、二氧化碳之间的液-液界面以及水与氙气的液-气界面上水合物的形成进行了全面的研究。通过对水合物稳定区内外的X射线反射率测量，研究了静态条件下水合物界面的结构。在水和液态烷烃之间的界面上，没有发现结构变化的证据。相反，在水-氙气和液-液-水-二氧化碳界面处观察到客体分子在纳米界面层内的积累。我们发现，在我们的观测时间内(∼12h)，只有那些最初表现出这种客体富集界面层的体系才会发展成宏观的气体水合物。瑟夫..。
The formation of hydrates, cage-like water-gas structures, is of tremendous importance both in industries and research. Although of major significance, the formation process is not completely understood so far. We present a comprehensive study of hydrate formation at liquid–liquid interfaces between water and isobutane, propane, carbon dioxide, and at the liquid–gas interface between water and xenon. We investigated the structure of these interfaces under quiescent conditions in situ by means of X-ray reflectivity measurements both inside and outside the zone of hydrate stability. At the interfaces between water and liquid alkanes, no evidence for a structural change was found. In contrast, the accumulation of guest molecules inside nanothick interfacial layers was observed at the water–xenon and liquid–liquid water–CO2 interfaces. We show that only those systems initially exhibiting such guest-enriched interfacial layers developed into macroscopic gas hydrates within our observation times (∼12 h). Theref...