title: EU-12: A Small-Pore, High-Silica Zeolite Containing Sinusoidal Eight-Ring Channels.
abstract: Zeolite EU-12, the framework structure of which has remained unsolved during the past 30 years, is synthesized at a specific SiO2 /Al2 O3 ratio using choline as an organic structure-directing agent, with both Na(+) and Rb(+) ions present. Synchrotron powder X-ray diffraction and Rietveld analyses reveal that the EU-12 structure has a two-dimensional 8-ring channel system. Among the two distinct 8-ring (4.6×2.8 and 5.0×2.7 Å) channels along c axis, the smaller one interconnects with the sinusoidal 8-ring (4.8×3.3 Å) channel along a axis. The other large one is simply linked up with the sinusoidal channel by sharing 8-rings (4.8×2.6 Å) in the ac plane. The proton form of EU-12 was found to show a considerably higher ethene selectivity in the low-temperature dehydration of ethanol than H-mordenite, the best catalyst for this reaction.
authors.affiliation: Center for Ordered Nanoporous Materials Synthesis, School of Environmental Science and Engineering, POSTECH, Pohang, 790-784, Korea.
authors.forename: Juna
authors.initials: J
authors.lastname: Bae
authors.affiliation: Center for Ordered Nanoporous Materials Synthesis, School of Environmental Science and Engineering, POSTECH, Pohang, 790-784, Korea.
authors.forename: Jung
authors.initials: J
authors.lastname: Cho
authors.affiliation: Center for Ordered Nanoporous Materials Synthesis, School of Environmental Science and Engineering, POSTECH, Pohang, 790-784, Korea.
authors.forename: Jeong Hwan
authors.initials: JH
authors.lastname: Lee
authors.affiliation: Center for Ordered Nanoporous Materials Synthesis, School of Environmental Science and Engineering, POSTECH, Pohang, 790-784, Korea.
authors.forename: Sung Man
authors.initials: SM
authors.lastname: Seo
authors.affiliation: Center for Ordered Nanoporous Materials Synthesis, School of Environmental Science and Engineering, POSTECH, Pohang, 790-784, Korea. sbhong@postech.ac.kr.
authors.forename: Suk Bong
authors.initials: SB
authors.lastname: Hong
keywords: aluminosilicates; ethanol dehydration; microporous materials; structure elucidation; zeolites