Adsorption of chromium (VI) via adsorptive PES-HFO ultrafiltration mixed matrix membrane

Abstract

In this work, novel Polyethersulfone (PES)/hydrous ferric dioxide (HFO) ultrafiltration (UF) mixed matrix membranes (MMMs) were prepared for adsorptive removal of Chromium(VI) by varying the weight ratio of HFO:PES in the membrane from 0 to 1.5. The membranes prepared were characterized with respect to chemical structure, surface roughness and structural morphology using FTIR, AFM and SEM-EDX, respectively. The effects of HFO loadings on the membrane pure water flux, hydrophilicity, porosity and Cr (VI) adsorption capacity were also studied. The results showed that although the membrane pore size tended to decrease with increasing HFO:PES weight ratio, the membrane water flux was not negatively affected. Instead the membrane water flux was increased with increasing HFO loadings which was attributable to the decreased contact angle value (more hydrophilic), increased porosity and greater surface roughness. Of all the membranes studied, it is found that the MMM prepared from the highest HFO:PES ratio demonstrated the highest Cr (VI) uptake capacity and is comparable to other available commercial adsorbents.