RESEARCH – Milad Rabbani Esfahani

Functionalized Membranes and Adsorbents for Water/Wastewater Treatment and Desalination

Functionalized membranes represent an innovative evolution of traditional polymeric membranes used in water/wastewater treatment and desalination. These advanced membranes exhibit three key attributes: enhanced permeation, improved selectivity, and antifouling capabilities. The performance of functionalized nanocomposite membranes is intricately linked to the membrane fabrication method, the properties of the functionalizing agents, and the resultant membrane behavior.

The Esfahani Research Group employs a diverse array of membrane fabrication techniques and functionalization methods, utilizing various 3D and 2D additives, including Metal-Organic Frameworks (MOFs) and MXene, to develop functionalized membranes tailored for the selective removal of diverse contaminants. These contaminants may include Per- and Polyfluorinated Substances (PFAS), micro/nanoplastics, heavy metals, and urea from water. Our research is dedicated to addressing pressing environmental challenges by advancing the development of functionalized membranes and adsorbents for water and wastewater treatment, as well as desalination.

If you want to learn more about our cutting-edge research, explore our projects and publications to see how we’re making a difference in the field of membrane technology and water purification.

Metal Organic Framework- Functionalized – Membranes

Metal-Organic Frameworks (MOFs) have emerged as a highly promising class of porous crystalline materials. MOFs possess attributes such as exceptional porosity, a high surface area, small particle size, tunability, compatibility with polymeric networks, and a rich diversity of functional groups. These characteristics make MOFs an ideal choice for functionalizing membranes. Furthermore, the organic ligands in MOFs enable them to form robust coordination interactions with polymeric membranes, resulting in enhanced membrane stability.

Given the remarkable advantages of MOFs, researchers have synthesized MOF-functionalized membrane materials through various methods. These materials are being extensively investigated for their applications in water and wastewater treatment, as well as resource recovery. The Esfahani Research Group is actively engaged in exploring the synthesis and performance of different MOF-functionalized membranes for a wide range of applications in water treatment, wastewater treatment, and desalination. Our work seeks to push the boundaries of membrane technology and contribute to more efficient and sustainable separation processes.

PFAS Removal and Degradation

The removal and degradation of per- and polyfluoroalkyl substances (PFAS) have become paramount in the realm of water purification, owing to their wide-ranging sources and adverse health implications. The Esfahani Research Group has been at the forefront of innovative research endeavors focused on developing membrane-based and adsorbent-based technologies to facilitate the enhanced removal, selective elimination, and degradation of PFAS from water sources. The concern surrounding the presence of poly- and perfluoroalkyl substances (PFAS) in aquatic environments is universal, given their detrimental impact on both ecosystems and public health. Various adsorbents, ranging from carbon-based materials and ion exchange resins to biomaterials and polymers, have been employed to remove short-chain (C < 6) and long-chain (C > 7) PFAS from water, with varying degrees of success. The emergence of metal-organic frameworks (MOFs) as a novel generation of adsorbents has added a new dimension to this field. MOFs possess unique attributes such as exceptionally high surface area, tunable structures, and enhanced selectivity compared to conventional adsorbents.

Within the Esfahani Research Group, we have embarked on the synthesis and characterization of various MOFs, activated carbons (AC), and hybrid adsorbents, including MIL-101 (Cr), MIL-101 (Cr)–NH2, MIL-101 (Cr)@AC, and superfine activated carbon. These materials have shown promise in the removal of perfluorooctane sulfonic acid (PFOS) from water. Our investigations have delved into the adsorption mechanisms, kinetics, capacity, and overall performance of these adsorbents when dealing with different PFAS compounds in water matrices.

We are currently engaged in several projects supported by organizations such as the Environmental Protection Agency (EPA), the United States Geological Survey (USGS), the Department of the Interior (DOI), and the Alabama Department of Economic and Community Affairs (ADECA). These initiatives are aimed at developing membrane-based and adsorption-based techniques to enhance PFAS removal, underscoring our commitment to advancing water purification technologies and addressing the pressing issue of PFAS contamination.

Nanoplastics Removal: A Growing Environmental Concern

Nanoplastics have emerged as a pressing environmental concern, garnering significant attention due to their unique characteristics that pose challenges for their removal and their capacity to transport coexisting pollutants. These minuscule particles, measuring less than 1 μm in size, exhibit remarkable mobility and a tendency to accumulate, making them a toxic threat to terrestrial and aquatic ecosystems, as well as to human health. Nanoplastics have been linked to inflammatory responses and oxidative stress in living organisms. Recognizing the urgency of this issue, the Esfahani Research Group has embarked on comprehensive investigations into the removal of micro/nanoplastics, with a particular focus on polystyrene nanoplastics (PSNPs), from water.

Our research endeavors employ cutting-edge approaches, including the utilization of various Metal-Organic Frameworks (MOFs) and MOF-Functionalized Membranes, notably the chromium-based metal−organic framework known as Cr-MOF/MIL-101. Through these innovative methods, we aim to address the formidable challenge posed by nanoplastics and contribute to safeguarding the environment and human well-being.

End of Life Plastics as Starting Materials for Filtration and Barrier Applications

Funded by the National Science Foundation under award number 2029387

Patterned-MOF-Functionalized NF Membranes for Fracking Wastewater Treatment

Funded by the National Science Foundation under award number 1941700

Functionalized Magnetic Metal Organic Framework Thin-Film Nanocomposite Membranes with Real-Time Induced Vibrations for Enhanced Antifouling

Funded by Department of Interior – The Bureau of Reclamation Desalination and Water Purification Research Program

Enhanced PFAS removal through synergistic biofiltration and nanofiltration treatment: role of NOM-PFAS characteristics