Using a colander to separate pasta from the water in which it was cooked is a commonplace kitchen experience. But what about the cooking water that usually disappears down the drain? Suppose you had a colander with holes that could not only separate pasta and water, but just as easily remove the salt and starch added to the water in the cooking process — making the water so pure that it would taste great.
In principle, this is exactly what can be done with membrane separations, a valuable technology, made even more valuable in recent years thanks to the work of NJIT Distinguished Chemical Engineering Professor Kamalesh Sirkar, of Bridgewater. Last week, the NJIT Board of Overseers awarded him the Excellence in Research Prize and Medal for his body of work which includes 24 patents, more than 156 refereed journal articles, mentoring legions of working professionals (whom he thanked) and federal grants worth hundreds of thousands of dollars. Sirkar has worked at NJIT since 1992.
“I am honored to have been chosen for this award,” he told some 200 colleagues, friends of the university and students who gathered last week for the ceremony and his talk about the uses of membrane separation technology, especially in desalination.
Cynthia Mascone, editor-in-chief of Chemical Engineering Progress magazine, a publication of the American Institute of Chemical Engineers, based in New York City, who as a special guest presenter captivated the audience before she draped around Sirkar’s neck a four-inch medal on a red velvet ribbon. She told of meeting Sirkar some 20 years ago as a fledging reporter for the chemical engineering industry. He stood out even then for his kind willingness to answer queries and for intelligent, clear, original responses, she said. NJIT Board of Overseers Chair Emil C. Herkert and NJIT President Robert A. Altenkirch next presented an enlarged facsimile of a $10,000 check, also part of the prize. “The little check will soon be in the mail,” joked Altenkirch.
Today, membrane separation technology has secured niches in industries ranging from brewing beer to manufacturing pharmaceuticals. This technology is also integral to meeting stringent standards for the purity of the water and even air. It is key to preventing explosions in aircraft fuel tanks and helping people with kidney disease. “Membrane separation will become the best technology for future applications that require separating components in a liquid or gas,” he said. “You can achieve the highest levels of purity at costs lower than those of alternative processes.” Sirkar is NJIT Foundation Professor of Membrane Separations and director of the Center for Membrane Technologies.
The basic principles of membrane separation have been known for a long time. Intestines in animals and humans are semi-permeable membranes, and early experiments to study the process of separation were performed by chemists using samples of animal intestine. However, it wasn’t until the early 1960s that the use of membranes for separation applications turned the corner toward practicality when two UCLA researchers fabricated a synthetic membrane from a material similar to plastic.
The researchers demonstrated that reverse osmosis achieved with their membrane could reject salt and produce fresh water at a rate sufficient for real-world use. Today such plants are used in the US, Sirkar said. But not as much as they could be. He predicted that by 2040, most US water treatment plants will use this technology because of the obvious advantages. “It’s a compact technology with relatively low energy consumption that can operate at room temperature for many different applications. It’s also a green technology,” he said.
In Sirkar’s NJIT lab, recent groundbreaking work in the field has included a membrane distillation technique that can recover a larger fraction of water from brine than reverse osmosis; a selective protein ultrafiltration method that could rival chromatography as a process for protein purification; and gas permeation membranes that facilitate the separation of carbon dioxide from air by allowing the carbon dioxide to pass through the membrane up to eighteen-thousand times faster than oxygen and nitrogen.
Sirkar is a Fellow of the American Association for the Advancement of Science and a recipient of the prestigious Clarence G. Gerhold Award from the separations division of the American Institute of Chemical Engineers (AIChE). Four researchers from other institutions honored him by lecturing at the event how his work influenced their own. They were: D. Bhattacharyya, PhD, university alumni professor in the department of chemical and materials engineering at the University of Kentucky; G. Glenn Lipscomb, PhD, professor of chemical and environmental engineering at the University of Toledo; Arup K. SenGupta, PhD, P.C. Rossin Professor of Civil and Environmental Engineering and Chemical Engineering at Lehigh University; S. Ranil Wickramasinghe, PhD, professor, department of chemical and biological engineering at the School of Biomedical Engineering, Colorado State University.