Magnetic Active Water Filter Membrane for Induced Heating to Remove Biofoulants

Filter membrane processes are water purification methods that use a partially permeable membrane to separate contaminants from drinking water and wastewater. Although highly effective, they suffer from biofouling due to the aggregation of bacteria and contaminants from the filtrate, thus rendering the membrane unusable. Consequently, the membrane needs to be replaced on a regular basis, which interrupts filtration operation, reduces throughput and increases production cost. To address this issue, we have developed a new method to remove biofoulants via induction heating on a modified membrane with magnetite (Fe3 O4) magnetic nanoparticle (MNPs) coating. Under applied alternating magnetic field, the surface temperature of the MNPs coating reaches 180 oC with a heating rate of 1.03 oCs-1, which disintegrates biofoulants generated by model bacteria (Bacillus subtilis), and by those present in environmental water samples collected from a local lake. The heating process is capable of cleaning bio-foulants for ...