Early stage of swelling process of dehydrated montmorillonite through molecular dynamics simulation

Al-Zaoari，Kamal1,3; Zheng，Yuan Yuan1,4; Wei，Peng Chang1; Zhang，Li Lan1; Yin，Zhen Yu2

2022-05-01

10.1016/j.matchemphys.2022.126015

MATERIALS CHEMISTRY AND PHYSICS   影响因子和分区

0254-0584

1879-3312

The early stage of the swelling process of dehydrated montmorillonite (MMT) is crucial to understand the mechanism of swelling. In this study, molecular dynamics simulations and analyses are presented to examine the conditions under which water molecules adsorb into the MMT interlayer in the early stages. Dehydrated (no interlayer water molecule - 0 W) and slightly hydrated (one and two water molecules per unit cell -1 W and 2 W) models of montmorillonite in a free water box are first built out with three different compensated cations (Ca, K, or Li). Simulations are then carried out at 298 K and 324 K using the CLAYFF force field. All results show that no water molecules can be adsorbed into dehydrated MMT interlayers at those temperatures. The MMT swelling process starts with existing initial interlayer water molecules, which allows more water molecules to adsorb into the interlayer to cause MMT swelling. The size and the valence of the compensated cations have a significant effect on the swelling behavior of MMT, and the Ca-MMT has a stronger swelling ability than K-MMT and Li-MMT. However, the swelling capacity of Ca-MMT is inhibited in saltwater compared to that in pure water.

Cations Molecular dynamics Montmorillonite Saltwater Swelling

SCI ; EI

英语

其他

National Natural Science Foundation of China[52009149] ; Natural Science Foundation of GuangDong Basic and Applied Basic Research Foundation[2021A1515012612] ; Research Grants Council (RGC) of Hong Kong Special Administrative Region Government (HKSARG) of China[15217220]

Materials Science

Materials Science, Multidisciplinary

WOS:000821079700004

ELSEVIER SCIENCE SA

20221211832108

Clay minerals ; Molecules ; Positive ions ; Swelling

Minerals:482.2 ; Physical Chemistry:801.4 ; Atomic and Molecular Physics:931.3 ; Materials Science:951

MATERIALS SCIENCE

2-s2.0-85126661998

Scopus

1.School of Civil Engineering,Sun Yat-Sen University,Guangzhou,510275,China
2.Department of Civil and Environmental Engineering,The Hong Kong Polytechnic University,Kowloon,Hung Hom, Hong Kong,Hong Kong
3.Department of Ocean Science and Engineering,Southern University of Science and Technology,Shenzhen,518055,China
4.Southern Marine Science and Engineering Guangdong Laboratory,Zhuhai,China

Al-Zaoari，Kamal,Zheng，Yuan Yuan,Wei，Peng Chang,et al. Early stage of swelling process of dehydrated montmorillonite through molecular dynamics simulation[J]. MATERIALS CHEMISTRY AND PHYSICS,2022,283.

Al-Zaoari，Kamal,Zheng，Yuan Yuan,Wei，Peng Chang,Zhang，Li Lan,&Yin，Zhen Yu.(2022).Early stage of swelling process of dehydrated montmorillonite through molecular dynamics simulation.MATERIALS CHEMISTRY AND PHYSICS,283.

Al-Zaoari，Kamal,et al."Early stage of swelling process of dehydrated montmorillonite through molecular dynamics simulation".MATERIALS CHEMISTRY AND PHYSICS 283(2022).