Brush assisted layer-by-layer assembled lignin/polyelectrolyte membrane

Abstract A lignin/polyelectrolyte membrane was facilely fabricated by a novel brush assisted layer-by-layer (LBL) assembly approach using poly(allylamine hydrochloride) as a polycation, sodium lignin sulfonate (SLS) as a polyanion, and glutaraldehyde as a crosslinker. This approach favors the quick formation of an effective separation layer compared to the classical static LBL assembly. The obtained membrane exhibits high rejection to trivalent and tetravalent anion salts (> 90%), along with high permeate flux (up to 66.3 L m-2h-1). The ultrathin separation layer (15 nm) and excellent hydrophilicity favor the enhancement of the permeate flux. The abundant hydrophilic groups of the outermost SLS layer and negatively charged surface endow the membrane with good fouling resistance to bull serum albumin. The membrane also shows good stability on the separation performance.