Molecular Dynamics Simulation Of The Wettability On Mica Surface

The rapid development of economy along with the extensive use of non-renewable fossil fuels and it leads to a large number of air pollutants be released into the atmosphere,which brings the environmental problems such as global warming. How to collect and use carbon dioxide effectively has become a new topic in today's academic research. On the basis of present researches which conclude that CO2 geological storage is an effective means to solve the excess carbon dioxide emissions. To explore the factors of CO2 geological storage has become the research focus. Based on previous research conclusions, the wettability of solid surface is the main factor affecting CO2 geological storage,so the wettability on rock surface is of great significance to geological sequestration of carbon dioxide.The results of using molecular dynamics simulation method to explore how the pressure influences the contact angle of mica surface show that when the pressure is within the scope of 12-13.5 MPa,the contact angle on the surface of the mica in the system is bigger as the pressure increases, and when the pressure is about 11 MPa contact angle reach to 22°, shows that the contact angle and the pressure is not increasing with liner relationship.And we should not take the pressure as the sole criterion for contact angle. This paper use SPC/E as water molecular model of potential energy, EPM2 as carbon dioxide molecules of potential energy, rigid diatomic model for oxygen, the single atom model for argon gas.What is more, we use CHARMM force field for fluid, and force field compatible with CHARMM force field for mica.This paper also explores how the different gases influences the size of contact angle of the mica surface. In order to verify this conclusion, this paper constructs the molarity is 3:1 for both argon gas/carbon and oxygen/carbon dioxide system, and carries on the molecular dynamics simulation respectively.The results show that as for the different physical and chemical properties, argon gas can reduce the contact angle water on the mica surface. However, oxygen gas does not increases contact angle on mica surface and maybe this is because the interaction between oxygen and carbon dioxide.