Menachem Elimelech

Menachem Elimelech (Hebrew: מְנַחֵם אֱלִימֶלֶךְ) is the Sterling Professor of Chemical and Environmental Engineering at Yale University. Elimelech is the only professor from an engineering department at Yale to be awarded the Sterling professorship since its establishment in 1920. Elimelech moved from the University of California, Los Angeles (UCLA) to Yale University in 1998 and founded Yale's Environmental Engineering program.

Elimelech was elected a member of the National Academy of Engineering in 2006, and a foreign member of the Chinese Academy of Engineering in 2017, the Australian Academy of Technology and Engineering in 2021, the Canadian Academy of Engineering in 2022, and the National Academy of Engineering of Korea in 2022. He is recognized for his pioneering work on membrane processes for desalination and water reuse, materials for next-generation desalination and water purification membranes, membrane-based brine and wastewater management technologies, particle and microbial pathogen filtration, and environmental applications of nanotechnology. Several of his findings have become textbook materials and are applied to engineered systems.

Early life and education
Elimelech was born in Israel to an immigrant family from Morocco. His parents had no formal education. His mother’s family were Berber Jews who moved to Casablanca from the Saharan Desert. He grew up in the southern city of Beer Sheva in an immigrant absorption camp (Ma'abarot) and later in government subsidized housing. He attended elementary schools in the city and high school at the Ben Shemen Youth Village, an agricultural boarding school in central Israel.

Elimelech graduated with high distinction from the Hebrew University of Jerusalem with Bachelor of Science (BSc) and Master of Science (MSc)  degrees in 1983 and 1985, respectively. He earned his PhD in environmental engineering at the Johns Hopkins University in 1989 under the direction of Professor Charles R. O’Melia. His dissertation was titled “The Effect of Particles Size on the Kinetics of Deposition of Brownian Particles in Porous Media.”

Academic career
Following his PhD studies at the Johns Hopkins University, Elimelech accepted a faculty position as assistant professor in the Department of Civil and Environmental Engineering at UCLA. He rose to the rank of Associate Professor in 1994 and Full Professor in 1997. At UCLA, he also served as a Department Vice Chair.

In 1998, Elimelech accepted a position at the Chemical Engineering Department at Yale University as the Llewellyn West Jones Professor. After moving to Yale, he founded the Environmental Engineering Program. In 2005, he was appointed the Roberto Goizueta Professor and as the Chair of the Chemical Engineering Department (from 2005 to 2010). The Environmental Engineering program founded by Elimelech is currently part of the Department of Chemical and Environmental Engineering. In 2021, Elimelech was appointed the Sterling Professor of Chemical and Environmental Engineering. The Sterling professorship is the highest academic rank at Yale University.

Contributions to science and technology
Elimelech is the author of over 540 refereed journal publications. He is the most cited and impactful scholar in the field of environmental and water quality engineering, with over 148,000 citations and h-index of 200 (Google Scholar).

Elimelech authored invited perspective articles that helped to shape the research and engineering practice in water purification and desalination. One example is an article in Nature  (2008) on the state-of-the-art and future research on water purification. The article highlighted the science and technology being developed to improve the decontamination of water, as well as efforts to increase water supply through the safe reuse of wastewater and efficient desalination of seawater and brackish groundwater. Another example is an article in Science (2011) on the future of seawater desalination. The article analyzed the possible reductions in energy demand by state-of-the-art seawater desalination technologies, the potential role of advanced materials and innovative technologies in improving performance, and the sustainability of desalination as a solution to global water shortages. Another article published in Nature Reviews Materials (2016) focused on materials for next-generation desalination and water purification membranes. The article discussed the state-of-the-art existing membrane technologies for water purification and desalination, highlighted their inherent limitations, and established the urgent requirements for next-generation membranes.

Elimelech made contributions to the development of technologies for desalination and for the management of brines from inland desalination plants and industrial wastewaters, such as those produced in the oil and gas industry. Specifically, he advanced the use of ultrahigh-pressure reverse osmosis (UHPRO) as a technology to displace energy-intensive thermal evaporators that are commonly used for brine management). Elimelech has developed a membrane-based technology for concentrating brines, referred to as low-salt-rejection reverse osmosis (LSRRO).  Through detailed process engineering modeling he has shown that LSRRO can concentrate brines up to approximately 240 g/L total dissolved solids (TDS), which is the feed brine concentration for brine crystallizers. UHPRO and LSRRO have attracted industrial interest as they are expected to revolutionize low-energy, low-cost brine management. Elimelech’s pioneering research on another desalination technology, the forward osmosis (FO) process,  has also impacted the water industry. The development of the FO process resulted in new commercial activity, as evidenced by the large number of FO patents and companies.

Elimelech provided molecular level understanding of fouling phenomena, which led to the development of fouling mitigation techniques. He introduced the concept of cake-enhanced osmotic pressure and biofilm-enhanced osmotic pressure as important mechanisms for water flux decline in salt-rejecting membranes, such as reverse osmosis and nanofiltration. He developed theories and models for concentration polarization in membrane separations, providing analytical expressions for predicting water flux. Professor Elimelech and collaborators also provided a mechanistic understanding of salt transport in reverse osmosis membranes, introducing the solution-friction model to describe the coupled transport of salt and water in reverse osmosis membranes. He has shown that the five-decades solution-diffusion mechanism for water transport in reverse osmosis membranes is fundamentally flawed. He has shown that water transport in reverse osmosis membranes is governed by a pore flow mechanism driven by a pressure gradient within the membrane, not by a concentration gradient of water as proposed by the solution-diffusion model. This finding has implications for the design of next-generation reverse osmosis desalination membranes.

Elimelech co-authored the book Particle Deposition & Aggregation: Measurement, Modeling and Simulation. Elimelech advanced the understanding of the transport of colloidal particles and microbial pathogens in subsurface porous media. The paramount role geochemical heterogeneity in the form of iron oxide coatings on mineral grains was introduced, verified in laboratory and field experiments, and incorporated in transport models. With Nathalie Tufenkji, Elimelech developed a predictive equation for particle removal in granular filtration, which is applicable to deep-bed filtration in water treatment, riverbank filtration, and transport of particles in subsurface environments. This equation, commonly referred to as the Tufenkji and Elimelech equation, has become textbook material and has been widely used in academia, industry, and government agencies.

Elimelech addressed challenges in water filtration and supply through the engineered application of nanomaterials. Specifically, he demonstrated the incorporation of nanomaterials into membrane technologies for fouling control, performance enhancement, and energy savings, as well as the development of point-of-use filters for virus removal and inactivation. Notable among his works is the demonstration and elucidation of the mechanisms of bacterial inactivation by carbon nanotubes  and graphene oxide,  which was later applied to membranes and water filtration. Elimelech also demonstrated that nanotechnology can offer solutions to water problems facing the developing world. Elimelech and his group developed a multiwalled carbon nanotube filter for the removal and inactivation of pathogenic viruses and bacteria from polluted waters. The carbon nanotube filter demonstrated complete removal of bacteria by sieving and over 99.99% removal and inactivation of viruses by depth-filtration.

Elimelech has steered the membrane community to more relevant research that has direct impact on industry and humanity. He was the first to point out that research on ultrahigh water permeability reverse osmosis membranes will have negligible impact on energy consumption in desalination. Elimelech has shown that increasing water-salt selectivity (or salt rejection) would be much more beneficial. Elimelech demonstrated the relative insignificance of advanced materials in enhancing the energy efficiency of desalination technologies, while proposing more effective materials-based and process-level research directions. In addition to seawater desalination, Elimelech established the sweet spots for electrodialysis and reverse osmosis in brackish water desalination. Elimelech developed performance metrics for processes for harvesting energy from salinity gradient (blue energy), showing that such processes are viable only for very high salinity waters, much more than seawater. The conclusions of these studies and other related research had direct impact on funding agencies, thus directing research funds to more relevant research.

Awards and honors

 * Connecticut Medal of Technology (2024)
 * The International Water Association (IWA) Membrane Technology Award (2023)
 * Honorary doctorate, Ben-Gurion University, Israel (2023)
 * Association of Environmental Engineering and Science Professors Outstanding Doctoral Dissertation Award (Doctoral Student Cody L. Ritt) (2023)
 * Highly Cited Researcher, Clarivate (Web of Science) (each year from 2012 to present) (2022)
 * Election to the National Academy of Engineering of Korea (2022)
 * Prince Sultan Bin Abdulaziz International Prize for Water (Alternative Water-Resources Prize) (2022)
 * Election to the Canadian Academy of Engineering (2022)
 * American Chemical Society, Outstanding Achievements in Environmental Science and Technology Award (2022)
 * Election to the Australian Academy of Technology and Engineering (2021)
 * Association of Environmental Engineering and Science Professors Perry L. McCarty AEESP Founders’ Award (2021)
 * Fulbright Scholar, Ben Gurion University, Israel (2019)
 * Association of Environmental Engineering and Science Professors Outstanding Publication Award (with Nathalie Tufenkji) (2019)
 * Election to the Chinese Academy of Engineering (2017)
 * Association of Environmental Engineering and Science Professors Distinguished Lecturer for 2016-17 (2016)
 * Association of Environmental Engineering and Science Professors Outstanding Doctoral Dissertation Award (Doctoral Student Ngai Yin Yip) (2015)
 * Eni Award, ‘Protection of the Environment’ prize (2015)
 * Elected Fellow, Association of Environmental Engineering and Science Professors (2015)
 * Chinese Academy of Sciences Distinguished Scholar (formerly known as “Einstein Professorship”) (2015)
 * Association of Environmental Engineering and Science Professors, The Charles R. O’Melia Distinguished Educator Award (2014)
 * Association of Environmental Engineering and Science Professors, Outstanding Publication Award (with Amy E. Childress) (2012)
 * Super Reviewer Award, Environmental Science & Technology (2012)
 * Yale University Postdoctoral Mentoring Prize (2012)
 * American Water Work Association (AWWA), First Place Best Doctoral Dissertation Award (Doctoral Student Meagan Mauter) (2012)
 * The Simon W. Freese Environmental Engineering Award and Lecture, American Society of Civil Engineers, ASCE (2011)
 * Liza Cariaga-Lo Faculty Award for Diversity in Scholarship and Service, Yale University (2010)
 * World Class University Professor, Korea University, Seoul, Korea (2009)
 * Royal Academy of Engineering, Distinguished Visiting Fellowship at the University of Edinburgh (2009)
 * The American Institute of Chemical Engineers, Lawrence K. Cecil Award in Environmental Chemical Engineering (2008)
 * Election to the Connecticut Academy of Science and Engineering (2007)
 * Election to the United States National Academy of Engineering (2006)
 * Association of Environmental Engineering and Science Professors, Frontier of Research Award (2006)
 * American Water Work Association (AWWA) First Place Best Doctoral Dissertation Award (Doctoral Student Nathalie Tufenkji) (2006)
 * The Athalie Richardson Irvine Clarke Prize, National Water Research Institute (2005)
 * Excellence in Review Award, Environmental Science & Technology (2004)
 * Yale University Graduate Mentor Award (2004)
 * Association of Environmental Engineering and Science Professors Outstanding Publication Award (with Charles O’Melia) (2002)
 * Association of Environmental Engineering and Science Professors Outstanding Doctoral Dissertation Award (Doctoral Student Eric M.V. Hoek) (2002)
 * American Society of Civil Engineers, Walter L. Huber Civil Engineering Research Prize (1996)
 * W. M. Keck Foundation, Engineering Teaching Excellence Award (1994)
 * National Science Foundation, Research Initiation Award (1990)
 * Environmental Engineering and Chemistry Graduate Student Award, American Chemical Society-Division of Environmental Chemistry (1989)

Mentoring of graduate students and postdocs
Elimelech has advised 49 PhD students and 47 postdoctoral researchers. In recognition of his excellence and dedication in teaching and mentoring, he received the W. M. Keck Foundation Engineering Teaching Excellence Award in 1994, the Yale University Graduate Mentoring Award in 2004, and the Yale University Postdoctoral Mentoring Prize in 2012.

Visiting professorships

 * California Institute of Technology, 1996
 * Swiss Federal Institute of Technology (ETH Zurich), 1997
 * National University of Singapore, 2001, 2002
 * Korea University, 2009, 2010
 * University of Edinburgh, 2009
 * Ben-Gurion University, Israel, 2019

Representative advisory boards and committees

 * External Advisory Council, Andlinger Center for Energy and the Environment, Princeton University (2021–present)
 * Scientific Advisory Board, Moroccan Foundation for Advanced Science, Innovation and Research (MAScIR), Morocco (2020–present)
 * External Review Committee, Wetsus, European center of excellence for sustainable water technology, The Netherlands (2017)
 * External Review Committee, Nanyang Environment & Water Research Institute (NEWRI), Nanyang Technological University, Singapore (2016)
 * Chair, Scientific Advisory Board, Water Desalination and Reuse Center, KAUST (2012-2016)
 * Scientific Advisory Board, Singapore Centre on Environmental Life Sciences Engineering (SCELSE) (2010-2016)
 * National Academies (Institute of Medicine) Committee on Blue Water Navy Vietnam Veterans and Agent Orange Exposure (2010-2013)
 * External Review Committee, Faculty of Civil and Environmental Engineering, Technion – Israel Institute of Technology, 2010
 * National Academies Committee on Advancing Desalination Technologies (2006-2008)
 * Scientific Advisory Board, Zuckerberg Institute for Water Research, Ben-Gurion University, Israel, 2003-2020