Molecular insights into CO2 hydrate formation in the presence of hydrophilic and hydrophobic solid surfaces

doi:10.1016/j.energy.2021.121260

	Molecular insights into CO2 hydrate formation in the presence of hydrophilic and hydrophobic solid surfaces
	He, Zhongjin 1,2; Mi, Fengyi 2; Ning, Fulong 2
刊名	ENERGY
	2021-11-01
卷号	234 页码:9
关键词	Carbon dioxide hydrate Molecular dynamics simulation Hydrate formation Solid surface Hydrophobicity/hydrophilicity
ISSN号	0360-5442
DOI	10.1016/j.energy.2021.121260
通讯作者	Ning, Fulong(nflzx@cug.edu.cn)
英文摘要	Microsecond molecular simulations have been performed on CO2 hydrate formation in the slit-nanopores of graphite and hydroxylated-silica surfaces. The simulation results show that different hydrophilic/hydrophobic properties of graphite and silica surfaces exert substantially different effects on CO2 hydrate formation. It is found that hydrate nucleation requires high aqueous CO2 concentration, and the solid surface affects hydrate nucleation mainly by changing the aqueous CO2 concentration in the systems. The hydrophobic graphite surfaces could adsorb CO2 molecules so strongly that the surfaces are almost covered by CO2 molecules, thus, the aqueous CO2 concentration is lowered. On the contrary, a partially cylindrical CO2 nanobubble is adsorbed at the hydrophilic silica surface and results in a high aqueous CO2 concentration. In the slit-nanopores of graphite and silica surfaces, hydrate nucleation starts from the bulk region and then grows towards the surfaces. CO2 hydrate solids interact with the silica surfaces mainly via semi-cages, which are constituted by the strong hydrogen bonds formed between silanols and interfacial water. At the end of the simulation, the hydrophobic graphite surfaces are still covered by the strongly adsorbed CO2 molecules, preventing the formation of ordered interfacial water on the surfaces, which is previously reported to play a critical role in promoting hydrate formation. These molecular insights into the effects of solid surfaces on CO2 hydrate formation are beneficial to CO2 hydrate-based technologies, such as geological CO2 sequestration. (C) 2021 Elsevier Ltd. All rights reserved.
资助项目	National Natural Science Foundation of China[41976203] ; National Natural Science Foundation of China[21506178] ; National Key Research and Development Program of China[2018YFE0126400] ; Department of Natural Resources of Guangdong Province Project[GDNRC [2020] -047] ; Fundamental Research Funds for the Central Universities, China University of Geosciences (Wuhan)[CUGGC09] ; Key Laboratory of Gas Hydrate, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences[Y907kg1001]
WOS关键词	METHANE HYDRATE ; GAS HYDRATE ; CARBON-DIOXIDE ; DYNAMICS SIMULATIONS ; CH4 HYDRATE ; NUCLEATION ; DISSOCIATION ; GROWTH ; PHASE ; WATER
WOS研究方向	Thermodynamics ; Energy & Fuels
语种	英语
出版者	PERGAMON-ELSEVIER SCIENCE LTD
WOS记录号	WOS:000692117200009
资助机构	National Natural Science Foundation of China ; National Key Research and Development Program of China ; Department of Natural Resources of Guangdong Province Project ; Fundamental Research Funds for the Central Universities, China University of Geosciences (Wuhan) ; Key Laboratory of Gas Hydrate, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences
内容类型	期刊论文
源URL	[http://ir.giec.ac.cn/handle/344007/33845]
专题	中国科学院广州能源研究所
通讯作者	Ning, Fulong
作者单位	1.Chinese Acad Sci, Guangzhou Inst Energy Convers, Key Lab Gas Hydrate, Guangzhou 510640, Guangdong, Peoples R China 2.China Univ Geosci, Fac Engn, Natl Ctr Int Res Deep Earth Drilling & Resource D, Wuhan 430074, Hubei, Peoples R China
推荐引用方式 GB/T 7714	He, Zhongjin,Mi, Fengyi,Ning, Fulong. Molecular insights into CO2 hydrate formation in the presence of hydrophilic and hydrophobic solid surfaces[J]. ENERGY,2021,234:9.
APA	He, Zhongjin,Mi, Fengyi,&Ning, Fulong.(2021).Molecular insights into CO2 hydrate formation in the presence of hydrophilic and hydrophobic solid surfaces.ENERGY,234,9.
MLA	He, Zhongjin,et al."Molecular insights into CO2 hydrate formation in the presence of hydrophilic and hydrophobic solid surfaces".ENERGY 234(2021):9.