Development of adsorbents-based cellulose acetate mixed matrix membranes for removal of pollutants from textile industry effluent

Abstract

The influence of adsorbents like activated carbon (AC) and iron oxide nanoparticles (IO) on the filtration efficiency of polymeric ultrafiltration (UF) membranes is proposed to investigate by incorporating them in wt % of 0.25, 1.5 and 2.5 with cellulose acetate (CA). The completely homogenous CA/AC and CA/IO casting solutions were obtained by sonicating AC and IO, respectively in N, N'-dimethyl formamide (DMF) followed by mechanical stirring with CA. By dry/wet phase inversion technique, novel CA mixed matrix membranes (MMMs) were synthesized which were later evaluated for their characteristics using atomic force microscope (AFM), field emission scanning electron microscope (FESEM) and X-ray diffractometer (XRD). In comparison to the neat CA membrane, pure water flux of CA MMMs containing 2.5 wt % AC and 0.5 wt % IP were increased from 5.61 Lm-2h-1 to 11.22 and 7.17 Lm-2h-1, respectively. These results suggest that the higher addition of AC influenced the membrane permeability whereas the amount of IP is found not to be surpassed beyond 0.5 wt% for improved flux. The wettability found by contact angle analysis suggests the higher productivity of CA MMMs and are evident by the adsorption nature of the chosen fillers. The polymer enhanced UF studies for rejecting COD, BOD and dissolved salts from the textile industry effluent has also been performed. The significance of CA MMMs lies on higher rejection efficiency with no compromise in membrane permeability. © 2014 Penerbit UTM Press. All rights reserved.