Clay-based electrospun nanofibrous membranes for colored wastewater treatment

Novel montmorillonite (Mt) chitosan/poly(vinyl alcohol) (PVA) nanocomposite electrospun nanofibrous membranes (ENM) were prepared and utilized for the treatment of colored wastewater. The Mt. with different mass percentages (0, 1.0, 2.0 and 3.0 mass%) was added to the membrane structure, and its effect on morphology, pore size, porosity, mechanical strength, and permeation properties of ENM were investigated. The fabricated membranes were used as affinity membranes for dye removal with ultrafast permeating adsorption. The results showed that incorporating Mt. as a reinforcing agent improved the nanocomposite ENM resistance to compaction. Young's modulus for the prepared membranes increased from 0.89 MPa for chitosan/PVA ENM to 2.09 MPa for a nanocomposite ENM containing 1.0 mass% of Mt. The optimum concentration of Mt. that increased both water flux and dye removal was found to be 2.0 mass%. The optimized membrane provided 95% rejection of Basic Blue 41 (BB41) with a significantly high flux of 1765 L/m2 h under 0.4 bar operating pressure, effectively overcoming the trade-off between permeability and selectivity. Moreover, the prepared nanoclay-based ENM was found to be antifouling and reusable for several cycles of dye removal.