Magnetic Microgels: Design, Synthesis, and Application
Date
2024-04-30
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
Magnetite nanoparticles (NPs) have shown promising potential for different applications including drug delivery, magnetic resonance imaging, environmental remediation, and catalysis. However, the main challenge limiting the magnetite NP applicability is its tendency to aggregate. As a result, a lot of research has been conducted on magnetite NP stabilization to improve their suitability for different applications. This thesis goal was to investigate the incorporation of magnetite NPs into microgels as a stabilization technique of the magnetite NPs and evaluate the magnetite NP-microgel hybrid system for two specific applications I) magnetic reservoir monitoring, and II) Lead removal from water. Microgels based on poly(N-isopropyl acrylamide) (PNIPAM) containing different mole ratios of methacrylic acid (MAA) were designed as templates for the in-situ synthesis and incorporation of magnetite NPs. Subsequently, microgel colloidal stability regarding NaCl concentration and temperature was studied to assess their applicability for subsurface applications. It was shown that microgels with a PNIPAM/MAA mole ratio of 40/60 remained stable at elevated temperatures (80 °C) and salinity (up to 10 wt% NaCl) which makes them suitable for subsurface applications. Additionally, the core-flooding experiment indicated that the magnetite NPs-microgel is magnetically detectable and does not have permanent retention in the porous medium. The obtained results show that magnetite NP-PNIPAM-co-MAA microgel has great potential as a magnetic contrast agent for reservoir monitoring. Magnetite NPs incorporated into the PNIPAM microgel were used as adsorbent for Pb2+ removal from water. The designed adsorbent was efficient in Pb2+ removal from water with a maximum capacity of 46 mg Pb2+/g. The results indicated that using microgels as carriers for magnetite NPs is an effective method for adsorption applications due to the porous structure of the microgels which facilitates high mass exchange between magnetite NPs and aqueous medium. In conclusion, results obtained from this study show that the magnetite NP-microgel hybrid system as a multifunctional material provides design flexibility to create materials for applications in various fields including but not limited to lead uptake from water and magnetic reservoir monitoring.
Description
Keywords
magnetite nanoparticles, microgel, magnetic reservoir monitoring, environmental remediation, reservoirs, materials
Citation
Afsar, F. (2024). Magnetic microgels: design, synthesis, and application (Doctoral thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca.