Abstract
The mixture separation is of fundamental importance in the modern industry. The membrane-based separation technology has attracted considerable attention due to the high efficiency, low energy consumption, etc. However, the tradeoff between the permeability and selectivity is a crucial challenge, which is also difficult to adjust during the separation process. Based on the salt water-filled carbon nanotubes, a separation membrane with the adjustable molecular channels by the electric field is proposed in this work. The separation mechanism is clarified on the basis of the characteristic size of the molecular channel and the overall effective diameter of gas molecules. The molecular dynamics simulation is performed to examine the feasibility and validity of the designed separation membrane. The simulations on the binary gas mixture (H(2) and N(2)) reveal the flow control and high-purity separation as the electric field intensity varies. As for the mixed gas with the three components (H(2), N(2) and Xe), the successive separations and the switch between the high-efficiency and high-purity separation could be achieved only through adjusting the electric field intensity. This work incorporates the control into the membrane-based separation technology, which provides a novel solution for the complex industrial separation requirement.