Two-dimensional Montmorillonite membranes with efficient water filtration

Abstract Two-dimensional (2D) Montmorillonite (MMT) membranes have been developed by exfoliation MMT nanosheets and vacuum filtration, and their separation performances were investigated in details. The hydrated lamellar MMT membrane with a thickness of 600 nm shows a water permeance of 212.2 L/m2·h·bar and a rejection rate of 95.6% for Direct Black 38 (DB38). Moreover, the lamellar MMT membrane maintained high stability under acid and alkaline solutions, and the separation performance changed slightly after soaking in 0.5 M H2SO4, 0.5 M NaOH and 0.5 M HCl solutions, respectively. The MMT membrane also exhibited good resistance to shearing force during a 48 h of cross-flow filtration with a slight decrease of water permeance. In addition, a high flux recovery ratio of 88.2% was achieved for the MMT membrane after filtration of BSA solution, suggesting an excellent antifouling property of the MMT membrane. The high water permeance, excellent stability and antifouling property make these 2D MMT membranes promising in water filtration.