Naturally derived polysaccharides-modified PSF membranes: A potency in enriching the antifouling nature of membranes

Abstract

The present work investigates the antifouling properties and dye removal efficiency of lignocellulose and caramel induced polysulfone (PSF) membranes. The PSF-based flat sheet membranes were prepared via diffusion induced phase separation method using different additional amounts of lignocellulose (LGC) as a hydrophilic additive and caramel as a pore forming agent. The prepared membranes were structurally characterized using various techniques and their performance was evaluated by pure water flux and water uptake capacity. MWCO studies has also been carried out. The studies on rejection and fouling characteristics of membranes was assessed using bovine serum albumin (BSA). The LGC and caramel modified PSF membranes demonstrated a significantly enhanced flux of ~250 L/m2 h and the BSA rejection was found to be around 97% with a flux recovery ratio (FRR) of ~90%. Similarly, the removal efficiency of methylene blue and congo red dyes from lignocellulose induced membranes were found to be ~98% and the observed efficiency could be attributed to their rich adsorption and increased electrostatic repulsion respectively. In addition, the agglomerated congo red dye on the membrane was successfully recovered using ethanol and the membranes were reused several times with little compromise in flux and congo red rejection. Overall, the developed strategy opens up an effective possibilities to enhance the thermal and mechanical properties, hydrophilicity, permeability, antifouling properties and dye removal capacity of the PSF membranes.