Performance investigation on a self-powered microbial pollutant adsorption cell with N-LAC/PVDF cation exchange membrane

Abstract

A high-efficiency, self-powered microbial pollutant adsorption cell with an N-LAC/PVDF cation exchange membrane was proposed to remove metal ions and organic dyes in high-salt wastewater. Nitrogen-doped alkali lignin (N-LAC) was synthesized using chitosan nanoparticles (CS) and alkali lignin (AL) using a blending method. The N-LAC/PVDF cation exchange membrane was prepared by chemically grafting polyvinylidene fluoride (PVDF). With modification, hydroxyl, carboxyl, carbonyl, and other hydrophilicity groups were introduced into the cation exchange membrane. The addition of N-LAC improved the membrane's hydrophilicity and adsorption capacity. FITR and SEM, respectively, characterized the surface morphology of the exchange membrane. The result showed that the contact angle reached 74.89° when the amount of N-LAC was 1 wt.%, and the desalination efficiency was 93.5 %, which increased by 70 %. The adsorption capacity of organic dye Pb and metal ion MB was 91 % and 94 %, respectively, showing an increase of 31.9 % and 43.5 %.