Adsorptive removal of lead (Pb2+) ion from water using cellulose acetate/polycaprolactone reinforced nanostructured membrane

Nanostructured membranes of cellulose acetate (CA) with various polycaprolactone (PCL) loadings (0%, 10%, 20% and 30%) were produced via electrospinning process for the removal of Pb2+ ion from wastewater. Optimized electrospinning parameters were utilized: voltage supply (30 kV), temperature (25 degrees C), tip to collector distance (18 cm) and needle size (25 G). Certain characterization techniques were used to investigate the effect of PCL addition on CA nanostructured membranes. The surface morphology was examined through Scanning Electron Microscopy (SEM), and chemical composition and molecular structure were determined using Scanning Electron Microscope - Energy Dispersive X-ray Spectroscopy (SEM-EDX) and Fourier Transform Infrared Spectroscopy (FTIR), respectively. Results showed that the incorporation of PCL in CA produced finer fiber diameter which gave the membrane a larger surface area; thus, increasing the adsorption sites. Based on the results, adsorption capacity was improved from 43.96 mg Pb2+/g of pure CA membrane to 70.50 mg Pb2+/g of CA/PCL doped membrane. Moreover, the results of this experiment best fitted the pseudo second-order kinetics, and the Freundlich isotherm which appropriately describe the adsorption process. CA membranes are widely used in several separation processes, and the results showed, its capability can be further enhanced by the incorporation of PCL to produce nanostructured membranes.