Effect of guests on the adsorption interaction between a hydrate cage and guests

doi:10.1039/c6ra21513k

GIEC OpenIR > 中国科学院广州能源研究所

	Effect of guests on the adsorption interaction between a hydrate cage and guests
	Liu, Chanjuan 1,2; Zhang, Zhengcai 1; Guo, Guang-Jun 1
	2016
发表期刊	RSC ADVANCES
卷号	6 期号:108 页码:106443-106452
摘要	The adsorption interaction between a water cage and a guest molecule, shown by the potential of mean force (PMF), is key to understanding hydrate formation mechanisms. In this work, we performed a series of PMF calculations to investigate how the guests affect adsorption interactions. We considered spherical guests for five species of inert gases (He, Ne, Ar, Kr, and Xe), and non-spherical guests for carbon dioxide, hydrogen, hydrogen sulfide, ethane, and propane. The results show that the location of the first well of PMF mainly depends on the guest size (i.e., the kinetic diameter of the guest) rather than the guest structure; and the activation energy (the free energy difference between the first well and the first barrier) mainly depends on the water-guest cross interaction and the size of the adsorption face. An empirical criterion is suggested to distinguish the adsorption face (d(ring)/d(guest) < 1.72) and cage hole (d(ring)/d(guest) > 1.72) for a specific guest molecule, where d(ring) is the diameter of the circumcircle of a water ring in a cage and d(guest) is the kinetic diameter of the guest. Additionally, some interesting phenomena are observed. For example, CO2 has the smallest activation energy and a predominant orientation near the adsorption face. H2S and Kr have almost the same cage-guest adsorption interaction owing to their similar size. C3H8 has the largest distance for the first barrier of PMF so as to require the smallest critical concentration to trigger hydrate nucleation according to the cage adsorption hypothesis. The present observations are very helpful to understand hydrate formation mechanisms.
文章类型	Article
WOS标题词	Science & Technology ; Physical Sciences
DOI	10.1039/c6ra21513k
研究领域[WOS]	Chemistry
关键词[WOS]	HYDROGEN STORAGE ; CLATHRATE HYDRATE ; GAS HYDRATE ; MOLECULAR SIMULATIONS ; NUCLEATION ; METHANE ; GROWTH ; PHASES ; WATER
收录类别	SCI
语种	英语
项目资助者	National Natural Science Foundation of China(41372059) ; Strategic Priority Research Program of the Chinese Academy of Sciences(XDB10020301)
WOS类目	Chemistry, Multidisciplinary
WOS记录号	WOS:000389330700046
引用统计	被引频次：11[WOS] [WOS记录] [WOS相关记录]
文献类型	期刊论文
条目标识符	http://ir.giec.ac.cn/handle/344007/13993
专题	中国科学院广州能源研究所
作者单位	1.Chinese Acad Sci, Inst Geol & Geophys, Key Lab Earth & Planetary Phys, Beijing 100029, Peoples R China 2.Chinese Acad Sci, Guangzhou Inst Energy Convers, Key Lab Nat Gas Hydrate, Guangzhou 510640, Guangdong, Peoples R China
推荐引用方式 GB/T 7714	Liu, Chanjuan,Zhang, Zhengcai,Guo, Guang-Jun. Effect of guests on the adsorption interaction between a hydrate cage and guests[J]. RSC ADVANCES,2016,6(108):106443-106452.
APA	Liu, Chanjuan,Zhang, Zhengcai,&Guo, Guang-Jun.(2016).Effect of guests on the adsorption interaction between a hydrate cage and guests.RSC ADVANCES,6(108),106443-106452.
MLA	Liu, Chanjuan,et al."Effect of guests on the adsorption interaction between a hydrate cage and guests".RSC ADVANCES 6.108(2016):106443-106452.