Analysis of graphene as a potential filtration membrane for desalination at varying operating conditions using molecular dynamics simulation and response surface methodology

ABSTRACT Water scarcity is a critical global issue exacerbated by pollution and overuse, necessitating sustainable water management solutions. Desalination using membrane technology presents a promising approach for freshwater production. This study investigated the performance of nanoporous (NPG) membranes for desalination, focusing on the influence of pressure and temperature on water flux and ion rejection. Utilizing molecular dynamics (MD) simulations with the LAMMPS package, this study evaluates NPG membranes under various conditions of pressures and temperatures. The simulations demonstrate that increasing both the pressure and temperature enhances the water flux without compromising ion rejection. The results indicate that at 300 K and 50 MPa, the water flux exceeds 2000 L/m2 h bar, significantly outperforming traditional reverse osmosis membranes, which typically achieve a capacity of approximately 1 L/m2 h bar. These findings were validated experimentally, aligning with previous research and confirming the superior performance of NPG membranes. A statistical model derived from response surface methodology revealed a linear relationship between pressure, temperature, and water flux. The study concludes that NPG membranes offer a high efficiency and scalable solution for desalination, with significant potential for energy savings and cost reduction. This study underscores the viability of NPG membranes in addressing global freshwater shortages and provides a pathway for sustainable water production.