Hidrologia: Pesquisa Atual

Fabrication of New Photografted Charged Thin Film Composite (TFC) Nanofiltration Membrane Applied to Waste Water Treatment: Effect of Filtration Parameters on the Rejection of Salts and Dyes

Abstract

Ahmad Akbari, Maryam Homayoonfal and Vahid Jabbari

Composite nanofiltration (NF) membrane was developed polyacrylic acid (PAA) in situ UV graft polymerization process using ultrafiltration polysulfone (PSf) membrane as porous support. Through the observation using SEM, the PSf UF membranes fabricated by phase inversion method, demonstrated numerous finger-like pores. AFM microscopy showed the roughness of surface was reduced by increase of UV irradiation times. The feasibility of membrane processes for treating simulated mixture by varying the feed pressures (1–4 bars), feed pH and UV irradiation times studied to assess the separation performance of NF membranes. The rejections of sodium chloride and sodium sulfate were moderate and declined with the increase of concentration. Color removal by NF with a high rejection of 99.90% was achieved. It was found that the efficiency of NF membranes used in the treatment of colored water effluents was greatly affected by the presence of salts and dyes in the mixture and the retention of dyes decreased with the salt concentration due to a decrease of the Donnan effect.