Magnetic Active Water Filter Membrane for Induced Heating to Remove Biofoulants

Abstract

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 (Fe3O4) magnetic nanoparticles (MNPs) coating. Under applied alternating magnetic field (AMF), the surface temperature of the MNPs coating reaches 180 °C with a heating rate of 1.03 °C/s, 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 biofoulants for several cycles without damaging the filtration function of the membrane. Furthermore, magnetic induction heating on the modified membrane allows uniform high-intensity heat generation on a large surface in only a few minutes using inexpensive MNPs, which can potentially be scaled up for industrial applications.

Stable Iron Oxide Nanoflowers with Exceptional Magnetic Heating Efficiency: Simple and Fast Polyol Synthesis

“…The heat magnetic nanoparticles generate when exposed to an alternating magnetic field is the basis for many applications including catalysis, antimicrobial materials, , and the most well-known and challenging magnetically induced hyperthermia (MIH) for cancer treatment. , …”

Direct Probing of Fe3O4 Nanoparticle Surface Temperatures during Magnetic Heating: Implications for Induction Catalysis

“…In situ heating with magnetic nanoparticles (NP) is now ubiquitous in applications such as induction heating catalysis, 1−5 thermoactivated drug delivery, 6,7 magnetic fluid hyperthermia, 8,9 and water treatment. 10 These technologies represent remarkable advances in nanotechnology and energy efficiency, which benefit from fast heating and cooling, local heating without increasing the temperature of the surroundings substantially, 11 and process safety. 12 However, to optimize heating processes with magnetic NPs via induction heating, a more detailed understanding of heat propagation at the nanoscale and an accurate determination of the NP surface temperature are still needed.…”

“…In situ heating with magnetic nanoparticles (NP) is now ubiquitous in applications such as induction heating catalysis, − thermoactivated drug delivery, , magnetic fluid hyperthermia, , and water treatment . These technologies represent remarkable advances in nanotechnology and energy efficiency, which benefit from fast heating and cooling, local heating without increasing the temperature of the surroundings substantially, and process safety .…”

Efficient Thermal Processes Using Alternating Electromagnetic Field for Methodical and Selective Release of Hydrogen Isotopes

“…6,7 It has been exploited in cancer therapy, 18 welding and soldering, 19 and thermoplastic processing 20 among others. 6,7,21 The use of the AEMF technology as an alternative to the indirect heating methods offers many significant advantages. For example, electromagnetic energy is noncontact and can be directly coupled to magnetic materials for localized and targeted heating.…”

“…One innovative and efficient strategy that could promote safe and controlled hydrogen release with less energy input involves the use of alternating electromagnetic fields (AEMF). , It has been exploited in cancer therapy, welding and soldering, and thermoplastic processing among others. ,, The use of the AEMF technology as an alternative to the indirect heating methods offers many significant advantages. For example, electromagnetic energy is noncontact and can be directly coupled to magnetic materials for localized and targeted heating.…”