About

Menachem Elimelech is the Nancy and Clint Carlson Professor in the Department of Civil and Environmental Engineering at Rice University. His research focuses on the water-energy nexus, specifically membrane-based processes for energy-efficient desalination and wastewater reuse, advanced materials for environmental separation and water decontamination technologies, and environmental applications of nanomaterials. He has authored more than 560 refereed journal publications, including invited review articles in Science and Nature, and is a co-author of the book Particle Deposition and Aggregation (1995). Professor Elimelech is recognized as a Clarivate Highly Cited Researcher and has received numerous awards for his contributions to environmental engineering and water research, including election to the United States National Academy of Engineering, the Chinese Academy of Engineering, the Australian Academy of Technology and Engineering, the Canadian Academy of Engineering, and the National Academy of Engineering of Korea. He has advised 56 Ph.D. students and 56 postdoctoral researchers, many of whom hold leading positions in academia and industry. His educational background includes a B.S. and M.S. from Hebrew University of Jerusalem and a Ph.D. from Johns Hopkins University.

Research topics

• Chemistry
• Materials science
• Nanotechnology
• Chemical engineering
• Organic chemistry
• Engineering
• Environmental science
• Computer Science
• Process engineering
• Composite material
• Environmental engineering
• Biochemical engineering
• Waste management
• Thermodynamics
• Electrical engineering
• Chromatography
• Photochemistry
• Computer Security
• Polymer chemistry
• Biology
• Risk analysis (engineering)
• Combinatorial chemistry
• Environmental planning
• Medicine

Selected publications

• Predicting concentration polarization in Ortho-Centrifugal Membrane Filters for NF/RO membrane screening

  SSRN Electronic Journal · 2026-01-01

  preprintOpen accessSenior author
  PublisherDOI

• The Future of Municipal Wastewater Reuse Concentrate Management: Drivers, Challenges, and Opportunities

  UNC Libraries · 2026-04-15

  articleOpen access

  Water reuse is rapidly becoming an integral feature of resilient water systems, where municipal wastewater undergoes advanced treatment, typically involving a sequence of ultrafiltration (UF), reverse osmosis (RO), and an advanced oxidation process (AOP). When RO is used, a concentrated waste stream is produced that is elevated in not only total dissolved solids but also metals, nutrients, and micropollutants that have passed through conventional wastewater treatment. Management of this RO concentrate─dubbed municipal wastewater reuse concentrate (MWRC)─will be critical to address, especially as water reuse practices become more widespread. Building on existing brine management practices, this review explores MWRC management options by identifying infrastructural needs and opportunities for multi-beneficial disposal. To safeguard environmental systems from the potential hazards of MWRC, disposal, monitoring, and regulatory techniques are discussed to promote the safety and affordability of implementing MWRC management. Furthermore, opportunities for resource recovery and valorization are differentiated, while economic techniques to revamp cost-benefit analysis for MWRC management are examined. The goal of this critical review is to create a common foundation for researchers, practitioners, and regulators by providing an interdisciplinary set of tools and frameworks to address the impending challenges and emerging opportunities of MWRC management.

  PublisherDOI

• A universal metric for classifying gas transport regimes in nanoconfined media

  The Journal of Chemical Physics · 2026-04-08

  articleSenior author

  Gas transport in nanoconfined media is fundamental to applications such as gas separation, catalysis, and shale gas extraction. While transport mechanisms in idealized rigid pores or simple fluids are well understood, classifying gas transport in complex soft matter and highly viscous liquids remains challenging. Here, we introduce a quantitative, physically grounded framework for classifying gas transport regimes based on the intrinsic dependence of gas diffusivity on molecular mass. Using molecular dynamics simulations, we systematically examine how gas diffusion coefficients scale with molecular mass across a broad range of nanoconfined media. We define a diffusivity-mass scaling exponent (α) that serves as a mechanistic fingerprint of the transport regime: α values near zero correspond to random diffusion, whereas values approaching -0.5 indicate transport regimes dominated by rigid pore confinement, such as Knudsen, surface, or hopping diffusion. This metric enables the quantitative identification of gas transport mechanisms and captures critical regime transitions of gas nanoflow that have previously been difficult to classify. Further analysis reveals that the molecular mass dependence arises from variations in characteristic step length, governed by molecular momentum and gas-medium interactions. The proposed mass-scaling framework provides a unified and objective criterion for identifying gas transport mechanisms in nanoconfined systems, laying the foundation for a general theory of nanoscale gas transport and enabling more reliable prediction and design of gas-transport materials.

  PublisherDOI

• Resilient high-temperature reverse osmosis desalination membranes

  Science Advances · 2026-01-14

  articleOpen access

  Conventional thin-film composite (TFC) reverse osmosis (RO) membranes experience irreversible performance loss at high temperatures, restricting their use in industries with high-temperature streams, including oil and gas, pharmaceuticals, electronics, power generation, food production, and hybrid desalination plants. However, the mechanisms driving the performance decline of TFC membranes at high temperatures remain poorly understood. Herein, we combine controlled experiments, molecular dynamics simulations, and micromechanical modeling to elucidate TFC failure mechanisms and to evaluate thermally resilient thin-film cross-linked (TFX) composite membrane. Upon exposure to elevated temperatures (>60°C), salt rejection of TFC dropped from ~99 to <90%, with irreversible structural damage in the polysulfone layer, confirmed by scanning electron microscopy. In contrast, the TFX membrane maintained ~99% salt rejection and showed no signs of physical degradation up to 80°C. Our combined analyses revealed that TFC membrane failure arises from irreversible pore expansion in the thermoplastic polysulfone support, leading to polyamide film rupture and delamination. TFX membranes resist thermal deformation, enabling ultrahigh-temperature RO desalination and water reuse.

  PublisherDOI

• Macrocycle-assembled membranes for high-salinity organic wastewater treatment

  Nature Communications · 2026-01-17 · 2 citations

  articleOpen accessSenior author

  Membrane processes offer a promising pathway for selectively separating organics and salts to enable water reuse and resource recovery. While polymeric membranes incorporating macrocyclic molecules that feature amphiphilic nature and tunable cavities are well suited for this purpose, traditional macrocycles with limited reactive sites and uncontrolled diffusion are challenging to be assembled into highly interconnected membranes. Here, we introduce tetra-aldehyde appended calixarene (TACA), a macrocyclic monomer featuring three-dimensional cavity and moderate reactivity, for creating loose-structured nanofilms via unidirectional diffusion assisted interfacial polymerization (UDIP). Precise positioning of the lipophilic TACA at the organic phase boundary allows it to polymerize with aqueous-phase diamines on the hydrogel surface, facilitating an undisturbed environment for controlled polymerization. The resultant thin macrocycle-assembled membranes featuring intrinsic water-facilitated through-cavity exhibited high water permeability of 63.8 L m-2 h-1 bar-1, and exceptional dye/salt selectivity and structural robustness, as evidenced by efficient diafiltration of binary dye/salt mixtures and superior operational stability. This work highlights the potential of macrocycle-assembled membranes for high-salinity organic wastewater treatment. Macrocyclic polymer membranes are well suited for wastewater treatment, though it is challenging to fabricate porous networks using macrocycles. Here the authors report a membrane containing tetraaldehyde appended calixarene using a unidirectional diffusion assisted interfacial polymerization method for a wastewater treatment membrane.

  PublisherOA PDFDOI

• Dual-regulated covalent organic framework membranes with near-theoretical pore sizes for angstrom-scale ion separations

  Science Advances · 2025-11-12 · 15 citations

  articleOpen accessSenior authorCorresponding

  Fabricating covalent organic framework (COF) membranes with molecular size cutoffs matching theoretical pore sizes is essential for selective angstrom-scale aqueous separations. We report a dual-regulation interfacial polymerization strategy to fabricate COF membranes with pore sizes approaching theoretical values, using Brønsted acid and organobase in separate phases to synchronously control polymerization and self-healing, as supported by molecular simulations of monomer diffusion and liquid chromatography–mass spectrometry analysis for component tracing. The dual-regulation COF membranes achieve a selectivity of 267 in single-salt test and an actual selectivity of 234 for K + /Mg 2+ in binary systems, demonstrating a threefold increase in mono/divalent cation separation compared to single-phase–regulated membranes. Additionally, we elucidate the untrapped and trapped transport of hydrated monovalent and divalent cations within the confined cavities through molecular dynamics simulations. This work provides an alternative approach to COF membrane fabrication and advances their application in precise sieving for water purification and resource recovery.

  PublisherDOI

• Non-equilibrium molecular simulations reveal a pore-flow-dominated transport mechanism in pervaporation membranes

  Desalination · 2025-10-01 · 7 citations

  articleSenior authorCorresponding
  PublisherDOI

• Solvent Transport in Disordered and Dynamic Membrane Pores: Implications for Reverse Osmosis and Nanofiltration Membranes

  Environmental Science & Technology · 2025-08-15 · 9 citations

  articleOpen accessSenior authorCorresponding

  Pressure-driven separations with nanoporous membranes, such as reverse osmosis and nanofiltration, play a vital role in addressing water scarcity and enabling resource recovery. Understanding water or solvent transport in membrane pores is essential for advancing membrane separation technologies. A key question in transport modeling is to establish a relationship between solvent permeability and membrane porous structure properties, such as porosity or pore size. The nano- and subnanometer pores in polymeric membranes such as reverse osmosis and nanofiltration membranes are highly tortuous and dynamically connected, which challenges the conventional methods of transport modeling. This study addresses this challenge by developing a theoretical framework to describe solvent transport through membranes with dynamic and disordered porous structure. Specifically, we propose a lattice model to describe the pore network, while preserving the viscous nature of solvent permeation. We further establish a relationship between solvent permeability and membrane porosity or pore size, which is validated by molecular dynamics simulations and experimental data. By integrating this relationship into the solution-friction model, we define pore connectivity and local friction coefficient to quantify the impact of pore structure on solvent permeability. Our analysis highlights the dominant influence of pore connectivity on the permeability of reverse osmosis and nanofiltration membranes, particularly when the pore size approaches the dimensions of solvent molecules. Overall, this study provides critical insights into water and solvent transport mechanisms in nanoporous membranes, opening the door for strategies to substantially enhance membrane performance.

  PublisherOA PDFDOI

• A covalent organic framework membrane with highly selective and permeable artificial sodium channels via ion recognition

  Nature Communications · 2025-08-09 · 15 citations

  articleOpen accessSenior author

  Biological sodium channels efficiently discriminate between same–charge ions with similar hydration shells. However, achieving precise ion selectivity and high throughput in artificial ion channel fabrication remains challenging. Here, we investigate angstrom–scale channels in 15-crown-5 (15C5) functionalized COF membranes for fast, selective ion transport. Due to crown ether recognition of sodium ions, channels in DHTA-Hz-15C5 membranes selectively facilitate Na+ transport, further enhanced by the hydroxyl-enriched COF skeleton. A Na+/K+ selectivity of 58.31 is achieved with 9.33 mmol m−2 h–1 permeance, significantly exceeding current membranes and resembling biological channels. Theoretical simulations indicate one–dimensional COF channels facilitate transport, while crown ether recognition makes the Na+ energy barrier significantly lower than K⁺, enabling ultrahigh selectivity with high Na⁺ permeability. This promotes COFs for efficient single-ion transport and advances crown ether ion selectivity in nano-restricted environments. Discriminating between ions with the same charge and similar hydration shells with artificial ion channels is challenging. Here, the authors produced crown ether functionalized covalent organic framework membranes for fast and selective sodium transport.

  PublisherOA PDFDOI

• Doctor-blading-assisted interfacial polymerization for green and scalable polyamide membrane fabrication

  Nature Communications · 2025-11-25 · 1 citations

  articleOpen accessSenior authorCorresponding

  Industry-leading polyamide membranes are thin-film composites produced via interfacial polymerization (IP) at an alkane-water interface. However, the current fabrication method results in suboptimal membrane microstructure and compromised performance due to insufficient control of mass and heat transfer within the interfacial reaction zone. Furthermore, the fabrication process utilizes volatile alkane solvents, contributing to a significant environmental burden. Here, we report an IP strategy at an ionic liquid/water interface to synchronously achieve kinetic and thermodynamic control of the interfacial reaction, thereby optimizing the microstructure of polyamide membranes. The high viscosity and low volatility of the ionic liquid facilitate the integration of the industrial doctor blading technique into the IP process, enabling rapid, eco-friendly, and scalable polyamide membrane production. The resulting membrane exhibits an unprecedented combination of high pure water permeance (25.8 LMH/bar) and excellent salt (sodium sulfate) rejection (96.54%), surpassing the performance of commercial benchmark polyamide membranes. This facile fabrication strategy paves the way for the design and production of next-generation, high-performance thin-film composite membranes. Polyamide membranes are often fabricated using interfacial polymerization methods, though these methods can compromise membrane structure and performance. Here the authors design a polymerization method using ionic liquid and a doctor blading method to optimize membrane fabrication.

  PublisherOA PDFDOI

Recent grants

• Engineered Osmosis for Sustainable Production of Water and Energy: Development of High Performance Micromolded Membranes

  NSF · $370k · 2012–2015

• NSF-BSF: Selective Transport of Divalent Cations through Polymeric Membranes Using Host-Guest Chemistry

  NSF · $413k · 2021–2024

• Carbon Nanotubes in Soils: Transport, Filtration, and Impact on Soil Microbial Community

  NSF · $369k · 2008–2012

• SusChEM: Development of Next-Generation, Ultra-Selective Aquaporin-Based Membranes for Sustainable Water Purification

  NSF · $330k · 2014–2018

• Collaborative Research: Fullerene Aggregation in Aquatic Systems

  NSF · $198k · 2005–2008

Frequent coauthors

• Joseph N. Ryan

  University of Colorado Boulder

  69 shared

• Xinglin Lu

  CAS Key Laboratory of Urban Pollutant Conversion

  53 shared

• Akshay Deshmukh

  Yale University

  51 shared

• Chanhee Boo

  47 shared

• Sohum K. Patel

  Yale University

  39 shared

• Long D. Nghiem

  39 shared

• Ronald W. Harvey

  United States Geological Survey

  38 shared

• Nathalie Tufenkji

  McGill University

  36 shared

Education

• PhD

  Johns Hopkins University

  1989

Awards & honors

• Eni Prize for Protection of the Environment (2015)
• Election to the United States National Academy of Engineerin…
• Chinese Academy of Engineering (2017)
• Australian Academy of Technology and Engineering (2021)
• Canadian Academy of Engineering (2022)