Application of UV irradiation enhanced by CuS photosensitive nanoparticles to mitigate polysulfone membrane fouling

Abstract

In this research, enhanced ultraviolet (UV) irradiation was used to offer antifouling properties to the surface of polysulfone (PSf) membranes. For this purpose, a thin layer of polyacrylic acid (PAA) was grafted to the membrane surface through UV irradiation in order to synthesize PAA/PSf membrane. Aiming to enhance the performance of UV irradiation, copper sulfide (CuS) and acrylic acid coated copper sulfide (AA©CuS) nanoparticles were embedded in the acrylic acid thin layer where CuS/PAA/PSf and AA©CuS/PAA/PSf membranes were fabricated. Presence of CuS and AA©CuS enhanced the wavelength of excitability of polysulfone from 254 to 322 and 354 nm, respectively. Thus, UV irradiation for 165 min on the surface of PSf membrane caused heightened degree of grafting from 16 % for PAA/PSf to 19 and 46 % for CuS/PAA/PSf and AA©CuS/PAA/PSf membranes, respectively. UV Irradiation for 240 min in the presence of nanoparticles also caused the CuS/PAA/PSf and AA©CuS/PAA/PSf membranes to be 28 and 42 % more hydrophilic and 26 and 37 % less rough respectively compared to PAA/PSf membrane. The mentioned factors eventually contributed to 40 %, 23 %, and 20 % irreversible fouling for PAA/PSf, CuS/PAA/PSf, and AA©CuS/PAA/PSf membranes, respectively.