- Email: [email protected]
09-O-02-NMR crystallography of AlPO4-CJ2
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20-0-05Regeneration of supercritical carbon dioxide supported MFI zeolite and mesoporous silica membranes
by alumina
K.J. Chao *l, C.H. Kao I, Y.W. Chiu 2, X.R. Lin 2 and C.S. Tan .2
Departments of Chemistry I and Chemical Engineering 2, National Tsinghua University, Hsinchu 300, Taiwan e-mail." kjchao@mx, nthu. edu. tw The regeneration of supercritical carbon dioxide from a mixture containing caffeine by microporous MFI zeolite and mesoporous silica membranes supported on alumina was studied. The experimental data show that a caffeine rejection higher than 90% or 70% and a permeation flux of supercritical carbon dioxide more than 0.05 or 0.07 mol/mZ/s could be obtained at 10.5 MPa.
0 9 - Crystal Structure Determination (Wednesday am) 09-O-01 - Localisation of K + ions in (Na,K)-LSX and K-LSX zeolites by Rietveld analysis and 39K N M R spectroscopy. A new cationic site in the orthorhombic dehydrated K-LSX at room temperature J.L. Paillaud (a), P. Caullet (a), L. Delmotte (a), J.C. Mougenel (a), S. Kayiran (a) and B. Lledos (b)
a Ecole Nationale Sup~rieure de Chimie de Mulhouse, [email protected], France; b Air Liquide, Jouy-en-Josas, France A LSX zeolite sample was studied under its as-made form and its fully exchanged potassium form. Upon dehydration, a lowering of the symmetry is observable at room temperature. This phenomenon was confirmed by MAS NMR spectroscopy. The structure reveals for the first time a simultaneous occupancy of sites I and I' by potassium cations. This is due to a shift of site I from the centre of the D6R unit. 39Kwide line NMR spectroscopy confirms the Rietveld analysis, especially the absence of K + ions on site I in the as-made Na72,Kz4-LSXsample.
0 9 - 0 - 0 2 - N M R crystallography of AIPO4-CJ2 F. Taulelle and C. Huguenard
RMN et Chimie du Solide, UMR 7510 ULP-Bruker-CNRS, Universit6 Louis Pasteur, 4 rue Blaise Pascal, 67070 Strasbourg Cedex, France. e-mail. [email protected] AIPO4-CJ2 is an aluminophosphate with an open framework structure. This compound has been studied by in-situ NMR to follow its crystallogenesis. It has also been characterized recently by different types of high resolution solid state NMR methods. F-P and F-A1 MAS HETCOR have been used to prove the disordered nature of units building the solid, those with a fluorine in bridging position and those with hydroxide at the same bridging positions. A1PO4-CJ2 is considered here to illustrate its crystallographic structure determination by solid state NMR of the powder. The main steps of NMR crystallography are described in this contribution: topological analysis, space group and metric determination.
20-0-05Regeneration of supercritical carbon dioxide supported MFI zeolite and mesoporous silica membranes
by alumina
K.J. Chao *l, C.H. Kao I, Y.W. Chiu 2, X.R. Lin 2 and C.S. Tan .2
Departments of Chemistry I and Chemical Engineering 2, National Tsinghua University, Hsinchu 300, Taiwan e-mail." kjchao@mx, nthu. edu. tw The regeneration of supercritical carbon dioxide from a mixture containing caffeine by microporous MFI zeolite and mesoporous silica membranes supported on alumina was studied. The experimental data show that a caffeine rejection higher than 90% or 70% and a permeation flux of supercritical carbon dioxide more than 0.05 or 0.07 mol/mZ/s could be obtained at 10.5 MPa.
0 9 - Crystal Structure Determination (Wednesday am) 09-O-01 - Localisation of K + ions in (Na,K)-LSX and K-LSX zeolites by Rietveld analysis and 39K N M R spectroscopy. A new cationic site in the orthorhombic dehydrated K-LSX at room temperature J.L. Paillaud (a), P. Caullet (a), L. Delmotte (a), J.C. Mougenel (a), S. Kayiran (a) and B. Lledos (b)
a Ecole Nationale Sup~rieure de Chimie de Mulhouse, [email protected], France; b Air Liquide, Jouy-en-Josas, France A LSX zeolite sample was studied under its as-made form and its fully exchanged potassium form. Upon dehydration, a lowering of the symmetry is observable at room temperature. This phenomenon was confirmed by MAS NMR spectroscopy. The structure reveals for the first time a simultaneous occupancy of sites I and I' by potassium cations. This is due to a shift of site I from the centre of the D6R unit. 39Kwide line NMR spectroscopy confirms the Rietveld analysis, especially the absence of K + ions on site I in the as-made Na72,Kz4-LSXsample.
0 9 - 0 - 0 2 - N M R crystallography of AIPO4-CJ2 F. Taulelle and C. Huguenard
RMN et Chimie du Solide, UMR 7510 ULP-Bruker-CNRS, Universit6 Louis Pasteur, 4 rue Blaise Pascal, 67070 Strasbourg Cedex, France. e-mail. [email protected] AIPO4-CJ2 is an aluminophosphate with an open framework structure. This compound has been studied by in-situ NMR to follow its crystallogenesis. It has also been characterized recently by different types of high resolution solid state NMR methods. F-P and F-A1 MAS HETCOR have been used to prove the disordered nature of units building the solid, those with a fluorine in bridging position and those with hydroxide at the same bridging positions. A1PO4-CJ2 is considered here to illustrate its crystallographic structure determination by solid state NMR of the powder. The main steps of NMR crystallography are described in this contribution: topological analysis, space group and metric determination.