Synthesis of thin-film nanocomposite membranes using functionalized silica nanoparticles for water desalination with drastically improved properties

Abstract

A unique polyethersulfone (PES)-supported thin-film composite (TFC) membrane was optimally manufactured by blending the modified silica (m-silica) into its polyamide (PA) network via interfacial polymerization (PI). The prepared membrane was characterized, and its permeability, and retention of inorganic salts, as well as, metal ions, and oily pollutants were evaluated. The characterization findings validated the successful inclusion of m-silica into the membrane matrix, and the treated composite membrane's increased hydrophilicity and smoother surface. Filtration tests were performed on the prepared membrane to assess its permeability and separation capacity against salts, metallic ions, and organic pollutants. The permeability of the formed nanocomposite membrane was around 62 Lm−2 h−1 (LMH). Moreover, an excellent removal of 100% metal ions and organic contaminants, and about 95% salt components, was accomplished without affecting its high permeability. The incorporation of m-silica enhanced the hydrophilicity, roughness, and surface charge, and the PA layer thickness, which enhanced the function of the modified thin-film nanocomposite membrane over the bare membrane. The developed m-silica membrane can be an excellent alternative for water treatment due to its exceptional stability and outstanding performance in eliminating a broad spectrum of environmental contaminants.