The production of chips, integrated circuits, and high-precision instruments demands exceptionally stringent conditions regarding process environments and media purity. For online water quality monitoring and precision analytical instruments, efficient separation and stable mass transfer constitute critical processes. Membrane separation, as a low-energy-consumption separation technique, has progressively underscored the limitations of traditional polymeric separation membranes in terms of flux, selectivity, and long-term durability. At the micrometer to nanometer scale, short-range mass transfer and confined transport create unique physical conditions for molecular-level separation, distinct from those in macroscopic systems. Nanoporous graphene separation membranes, characterized by their atomic-level thickness (around 0.34 nanometers) and adjustable nanopore structures, have emerged as a promising two-dimensional functional membrane material. These membranes rely on micrometer to nanometer-scale fabrication techniques for precise structural control and offer potential solutions to overcome the flux and selectivity bottlenecks inherent in traditional polymeric materials.