(3fz) Ion Selective Membranes for the Recovery of Resources and Energy from "Waste" Streams

Research Background

3^rd year postdoc with broad experience in membrane separations. I have experience in the development of high-performance membranes using both inorganic (nanoporous single layer graphene, graphitic carbon nitride, zeolite nanosheets, MOFs) and organic (commercial and lab-made polymers; dense symmetric films; porous supports; composite membranes via interfacial polymerization, dip and spin coating; flat sheet and hollow fibers) materials. Moreover, I have participated in projects targeting a broad range of separations including gas separations (hydrogen recovery and carbon capture), nanofiltration, ultrafiltration, solvent resistant nanofiltration, catalytic membranes for water decontamination, water vapor removal, biofouling control and membrane adsorbents.

Research Interests

My research group will focus on the material chemistry and engineering for the development of membranes and membrane adsorbents for the recovery of resources (materials and energy) from “waste” streams. Our aim will be to develop and deploy sustainable technologies for the recovery of valuable ions, and the use of ion-rich streams to generate blue energy (i.e., osmotic power). We will follow a comprehensive approach to develop structure-function correlations to engineer how ions interact with nanoporous inorganic materials and polymers; and understand the most relevant physical and chemical phenomena at the material synthesis, membrane fabrication, and separation process levels. With this knowledge we will fabricate (i) ionophore membranes to recover ions from concentrated streams (e.g., NH₄⁺ (fertilizer)from urine, and Cu²⁺ from mining industry streams), (ii) ultrafiltration membrane adsorbents to recover ions from dilute streams (e.g., Li⁺ from seawater in reverse osmosis plants), and (iii) 2D nanoporous membranes (graphene and MoS₂) to recover energy from osmotic gradients (e.g., the streaming potential generated by Na⁺ or Cl^- ions passing through nanopores during the controlled mixing of fresh and salty water). Figure 1 shows some of the materials/transport mechanisms we will explore.

It is time to reimagine liquid waste streams as valuable products and energy sources. Membranes with the ability to discriminate molecules and particularly ions are extremely attractive for this propose. Membrane-based separations have low energy requirements, a compact design, and are mechanically simple making them ideal additions to existing processes where a valuable material or energy could be recovered. The state-of-the-art membranes are very good at rejecting ions, but they lack ion-specificity. The lack of membranes that can selectively permeate one ion and reject similarly sized and charged ions is a huge bottle neck in the field. If solved, membrane-based applications will revolutionize the way we treat “waste” streams.

Come to my poster to discuss more details about how I plan to build a research group to make and study ion-selective membranes to tackle these issues!

Teaching interests

I'm interested in teaching undergraduate or graduate core chemical engineering courses and also to develop the content and teach a highly interactive course about membrane technology and membrane-based separations.

Representative publications

• L.F. Villalobos, M. T. Vahdat, M. Dakhchoune, Z. Nadizadeh, M. Mensi, E. Oveisi, D. Campi, N. Marzari & K. V. Agrawal, "Large-scale synthesis of crystalline g-C₃N₄ nanosheets and high temperature H₂ sieving from assembled films", Science Advances, 6, eaay9851, 2020 [https://advances.sciencemag.org/content/6/4/eaay9851]
• L.F. Villalobos, R. Hilke, F. H. Akhtar & K.-V. Peinemann, "Fabrication of Polybenzimidazole/Palladium Nanoparticles Hollow Fiber Membranes for Hydrogen Purification", Advanced Energy Materials, 8, 1701567, 2018 [https://doi.org/10.1002/aenm.201701567]
• L.F. Villalobos, T. Huang & K.-V. Peinemann, "Cyclodextrin Films with Fast Solvent Transport and Shape-Selective Permeability", Advanced Materials, 29, 1606641, 2017 [https://doi.org/10.1002/adma.201606641]
• L.F. Villalobos, M. Karunakaran & K.-V. Peinemann, "Complexation-Induced Phase Separation: Preparation of Composite Membranes with a Nanometer-Thin Dense Skin Loaded with Metal Ions", Nano Letters, 15, 3166–3171, 2015 [https://doi.org/10.1021/acs.nanolett.5b00275]
• L.F. Villalobos, T. Yapici & K.-V. Peinemann, "Poly-thiosemicarbazide membrane for gold recovery", Separation and Purification Technology, 136, 94–104, 2014 [https://doi.org/10.1016/j.seppur.2014.08.027]