固体核磁共振技术在气体水合物研究中的应用

Applications of Solid State NMR in the Studies of Gas Hydrate

气体水合物是在低温高压条件下由气体和水形成的笼型化合物,主要有I型,II型和H型3种晶体结构,而固体核磁共振(solid state NMR)是测定其水合指数、笼占有率等结构参数的重要手段.该文综述了固体核磁共振技术的原理及其在水合物研究中的应用,着重介绍固体核磁共振在水合物结构表征、气体组分的鉴定、结构转化、以及在水合物生成/分解动力学过程监测方面的研究进展.同时,对其实验方法及测试条件也进行了详细的探讨.

Gas hydrate is a clathrate compound formed from gas and water under low temperature and high pressure. So far, three types of crystal structure （i. e. Ⅰ,Ⅱ and H） have been found for natural gas hydrate around the world. Solid state NMR provides an important tool for structure characterization of gas hydrate and for quantitative meas-urement of hydration number and cage occupancy. In this paper, the principles and ap-plications of solid state NMR techniques in studying gas hydrate were reviewed. Empha-sis was given on the progresses in structural characterization of gas hydrates, identifica-tion of gas molecules and studies on structure transform, as well as the in situ monito-ring of hydrate formation and dissociation. The experimental techniques and conditions for solid state NMR studies of gas hydrate were also discussed.