Study of the evolution of nano-bubbles/droplets generated in water by CO2-Hydrate dissociation via molecular- dynamics simulation.

In this study, molecular-dynamics simulations were used to evaluate the nano-bubbles/droplets generated in water by CO2 hydrate dissociation. Two different simulation sets of NVT (isothermal) and NPT (isobaric/isothermal) were conducted for different CO2 concentrations and compared. The results could confirm that the CO2 agglomeration behavior changed during the simulation and observed the coexistence of CO2 nano-bubbles and nano-droplets in both systems. At first, the nano-bubbles could only be observed in the system, but some of them were turned into nano-droplets as the simulation proceeded. The NVT system is feasible to generate nano-bubbles/droplets, and the local CO2 densities are higher for the NVT system, and it can also generate slightly larger CO2 agglomeration. A higher concentration of CO2 in the solution caused more nano-droplets in both sets, while a lower concentration may only produce nano-bubbles. [ABSTRACT FROM AUTHOR]