Study of magnetic-responsive nanoparticle on the membrane surface as a membrane antifouling surface coating

Abstract

This study aims to form a dynamic layer of the magnetic protective layer (f- Fe 3 O 4 /PDDA) on a surface of cellulose acetate (CA) membrane to prevent direct membrane-foulant interactions during an ultrafiltration process. To this end, Fe 3 O 4 nanoparticles with an approximate size of 151.8 ± 8.2 nm were spin-coated on the surface of CA membrane to provide magneto-induced actuation motions of the magnetic nano-colloid in 3-dimensional space, with the help of an external magnetic field (magnetic rod). ATR-FTIR, QCM-D, and cross-flow filtration of this magnetic-responsive membrane were investigated to determine its influences on surface fouling by humic acid solutions. In fact, ATR-FTIR and QCM-D analyses have demonstrated a minimum membrane fouling for the magnetic-responsive membrane that operated under the influence of an oscillating magnetic field. Cross-flow filtration results showed a practically higher permeation (retaining 54% of the initial flux at its steady-flow) and humic acid rejection (more than 85%) in the presence of an oscillating magnetic field compared to its performance in the absence of an oscillating magnetic field. Findings from this magnetically responsive membranes could represent a new class of fouling-resistant membrane.