Investigation On Hydraulic Permeability And Transport Of Graphene Based Structure

Graphene oxide is the two-dimensional carbon atomic structure with oxygen-containing functional groups at the edges.The graphene oxide membrane consists of multiple layers of go,with layers space of 0.83 nm.It has hydrophilic pores and hydrophobic paths that allow fast water transport,and can be used for separation and filtration.This paper focuses on the preparation and application of graphene oxide based composite structure and the transport process.We prepared non-woven fibrous interface with different sufface energy and grain interface of porous structure.We used drop casting method to prepare graphene oxide film on the interface.Based on energy minimization principle,we explored the influence of surface energy and surface structure on the formation of graphene oxide by observing the movement and film formation of graphene oxide.And we described the morphology of graphene oxide film(such as fold,etc.).This provides a theoretical basis for the further application of graphene oxide based composite structures.We prepared non-woven and quasi-parallel porous fibrous media.Through the hydraulic permeation experiment,the hydraulic permeability of the two media and the different changes under the hydraulic pressure caused by the different arrangement are explored.Based on the phenomenon of obvious hydraulic pressure accompanied by the graphene oxide dispersion passes through the porous medium,we explored the application of graphene oxide as the dynamic hydraulic barrier is explored.The effects of concentration and flow rate on the surface energy,pore size,thickness of the porous medium on the performance of graphene oxide as the dynamic hydraulic barrier are studied.Furthermore,we designed and set up a small air gap membrane distillation model,and applied graphene oxide-fibrous membrane composite structure in membrane distillation experiment\for the process of NaCl solution.We proved that the composite structure has good desalting performance and explored the transport process in the composite structure,namely the two-dimensional pore(graphene oxide film)-three-dimensional pore(fibrous membrane).We also study the mechanism of graphene oxide film for ions(Na~+and Cl~-)separation.