Thin-film zeolite membranes with tiny, molecule-sized pores are one step closer to replacing the energy-intensive processes now used in industrial separations, a group of academic researchers is reporting.
Writing this week in Science magazine, the group says the membranes' ability to separate molecules in a mixture is significantly improved by subjecting the zeolite to rapid thermal processing (RTP). By heating the membranes from room temperature to 700 degrees Centigrade in one minute, maintaining this temperature for up to two minutes and then quickly cooling it, the researchers say they have been able to eliminate the formation of grain boundary defects that undermine the sieve-like quality of zeolite's uniformly sized nanopores.
The research group, led by Michael Tsapatsis, Amundson Chair Professor of chemical engineering and materials science at the University of Minnesota, says RTP shows promise in achieving greater yield and energy efficiency in zeolite membrane production.
Tsapatsis' group reported its results in an article titled "Grain Boundary Defect Elimination in a Zeolite Membrane by Rapid Thermal Processing." The article was coauthored by Tsapatsis; Jungkyu Choi, formerly of the University of Minnesota and now a postdoctoral fellow at the University of California at Berkeley; Hae-Kwon Jeong, assistant professor of chemical engineering at Texas A&M University; Mark A. Snyder, assistant professor of chemical engineering at Lehigh University in Bethlehem, Pennsylvania; Jared A. Stoeger, a graduate student at the University of Minnesota; and Richard I. Masel, professor of chemical and biomolecular engineering at the University of Illinois at Urbana-Champaign.
Zeolites are crystalline aluminosilicate materials whose compositions and nanoporous structures can be fine-tuned for applications in catalysis, adsorption and ion exchange. They are called "molecular sieves" because their pores, being small and very u
|Contact: Kurt Pfitzer|