Ultra filtration (UF) membranes are widely applied for micromolecular solutes separation from aqueous streams especially in the field of effluent treatment of chemical process industries. A series of cellulose acetate (CA) blended with iron nanoparticles (modifier) ultrafiltration membranes were prepared by the phase-inversion technique in 100/0, 99.5/0.5, 98.5/1.5 and 97.5/2.5% polymer blend compositions. The membranes prepared were characterized in terms of compaction, pure water flux, membrane hydraulic resistance, thermo mechanical analysis and water uptake. Surface and cross-sectional morphologies of the membranes were analyzed with scanning electron microscopy (SEM) and atomic force microscopy (AFM). UF characterization studies clearly indicated the better performance of 99.5% CA - 0.5% iron nanoparticles blend membrane in comparison with other synthesized UF membranes. The 99.5% CA - 0.5% iron nanoparticles blend UF membrane was applied to study the rejection of sulphates & organics (in terms of BOD, COD level) for a textile industry effluent. The results indicated almost an equivalent solute rejection percentage (%SR) in comparison to pure CA membranes but with an increased flux rate of separation.