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Russell E. Morris - One of the best experts on this subject based on the ideXlab platform.
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Ionothermal synthesis - Ionic liquids as functional solvents in the preparation of crystalline materials
Chemical Communications, 2009Co-Authors: Russell E. MorrisAbstract:Ionothermal synthesis is the use of ionic liquids simultaneously as both the solvent and potential template or structure directing Agent in the formation of solids. It directly parallels hydrothermal synthesis where the solvent is water. In this feature article I discuss the general features of ionothermal synthesis and how the properties of the synthesis differ from those of other synthetic methodologies. In particular, I will discuss the role of the ionic liquid anion in determining the structure of the synthesised solid, the role of mineralisers such as water and fluoride, and the targeted use of unstable ionic liquids to produce new inorganic and inorganic-organic hybrid materials.
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1 alkyl 3 methyl imidazolium bromide ionic liquids in the ionothermal synthesis of aluminium phosphate molecular sieves
Chemistry of Materials, 2006Co-Authors: Russell E. MorrisAbstract:The systematic increase in alkyl chain length from 2 to 5 carbons in 1-alkyl-3-methyl imidazolium bromide ionic liquids is investigated in the ionothermal synthesis of aluminophosphate (AlPO) zeolite materials in sealed autoclaves. The effect of alkyl chain branching and the use of an imidazolium dication ionic liquid are also investigated. On addition of HF to the reaction mixture, a small amount of 1,3-dimethylimidazolium cation is formed in all cases (except when the alkyl chain length is 2), which acts as the structure directing Agent (SDA) in the formation of AlPO molecular sieves with the CHA framework (SIZ-10). For 1-ethyl-3-methyl imidazolium bromide ionic liquids, the cation is incorporated intact into the SIZ-4 structure. The resulting materials are characterized by single-crystal X-ray diffraction and 13C MAS NMR.
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Structure-Directing Agent location and non-centrosymmetric structure of fluoride-containing zeolite SSZ-55.
Journal of Physical Chemistry B, 2006Co-Authors: Allen W Burton, Russell E. Morris, Richard J. Darton, Mark E. Davis, Song-jong Hwang, Isao Ogino, Stacey I ZonesAbstract:Single crystals of pure silica zeolite SSZ-55 were prepared using the fluoride route. Single-crystal X-ray diffraction at a synchrotron source revealed the framework structure of the material, but the unit cell (orthorhombic a = 12.905(2) A, b = 21.344(4) A, c = 5.1279(10)) is too small to accommodate ordered arrays of the organic Structure-Directing Agent. Molecular modeling was used to simulate the docking of the Structure-Directing Agent in the channels of the material, and this revealed a strong space-filling interaction with a number of possible orientations of the organic cation. The overall non-centrosymmetric structure of the solid (spacegroup C222_1) was confirmed using second harmonic generation experiments.
Aisheng Huang - One of the best experts on this subject based on the ideXlab platform.
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Facile and reproducible synthesis of ITQ-29 zeolite by using Kryptofix 222 as the structure directing Agent
Microporous and Mesoporous Materials, 2010Co-Authors: Aisheng Huang, Claudia Weidenthaler, Jurgen CaroAbstract:In pioneering papers Corma et al. reported the synthesis of the Al-free zeolite ITQ-29 with LTA topology by using supramolecular self-assembled molecules as the organic structure directing Agent (SDA). However, the SDA used to synthesize ITQ-29 is not commercial and rather difficult to synthesize and purify. Thus the development of a more convenient and more effective method for the synthesis of ITQ-29 is highly desired. Therefore, in this communication we propose a facile and reproducible method to synthesize uniform and well-shaped ITQ-29 crystals by using the crown ether Kryptofix 222 as the SDA.
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Preparation of large and well-shaped LTA-type AlPO4 crystals by using crown ether Kryptofix 222 as structure directing Agent
Microporous and Mesoporous Materials, 2010Co-Authors: Aisheng Huang, Juergen CaroAbstract:In a detailed study, the influence of the most relevant synthesis parameters on the crystallization of LTA-type AlPO4 using Kryptofix 222 (K222) as structure directing Agent (SDA) was investigated with the aim to develop a reliable and reproducible strategy for the preparation of large and well-shaped crystals. Only with sufficient mixing time for the aluminophosphate gel before adding the SDAs, well-shaped cubic and large LTA-type AlPO4 crystals could be obtained. With increasing water content in the starting gel, the crystal size became larger and the cubic crystals displayed less truncated. Hydrofluoric acid was found to be a more efficient mineralizer to form large and well-shaped cubic crystals than ammonium fluoride. When Al(OH)3 was used instead of our standard aluminium source Al2O3, the crystal size was not influenced. When Al[OCH(CH3)2]3 was the aluminium source, the size of the LTA-type AlPO4 crystals decreased much, probably since a larger number of nuclei was formed upon hydrolysis of Al[OCH(CH3)2]3. When Al2(SO4)3 was used as aluminium source, no LTA-type AlPO4 crystals could be obtained. With increasing substitution of aluminium by gallium, the crystals size increased and the crystal surface became rough. All diffraction patterns of mixed (Al + Ga)PO4 crystals were characteristic of the LTA framework. The same Ga/Al and (Al + Ga)/P ratio of the synthesis gel was also found in the (Al + Ga)PO4 crystals. Low temperature in combination with long synthesis time was found to be beneficial for the preparation of large and well-shaped AlPO4 crystals. © 2009 Elsevier Inc. All rights reserved.
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Steam-stable hydrophobic ITQ-29 molecular sieve membrane with H2 selectivity prepared by secondary growth using Kryptofix 222 as SDA
Chemical Communications, 2010Co-Authors: Aisheng Huang, Jurgen CaroAbstract:A neutral framework cation-free hydrophobic ITQ-29 molecular sieve membrane with hydrogen selectivity was prepared on porous α-Al2O3 supports by using Kryptofix 222 as organic structure directing Agent through secondary growth method.
Tatsuya Okubo - One of the best experts on this subject based on the ideXlab platform.
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Seed-directed, rapid synthesis of MAZ-type zeolites without using organic Structure-Directing Agent
Microporous and Mesoporous Materials, 2014Co-Authors: Akari Ogawa, Kenta Iyoki, Yoshihiro Kamimura, Shanmugam Palani Elangovan, Keiji Itabashi, Tatsuya OkuboAbstract:Abstract MAZ-type zeolites (omega) were successfully obtained for the first time using a seed-directed, organic Structure-Directing Agent-free synthesis method according to the “Composite Building Unit Hypothesis” surprisingly in a short period ( ca. 30 h) of hydrothermal treatment. The obtained product showed textural and acidic properties that were superior to the omega seed crystals synthesized using tetramethylammonium hydroxide as an organic Structure-Directing Agent. Therefore, we believe the new technique is an efficient and environmentally friendly process for the preparation of MAZ-type zeolites for their use as adsorbents, catalysts, and so on. In addition, the “Composite Building Unit Hypothesis” was confirmed to be applicable for the synthesis of 4R-rich zeolites in the (Na, K)-aluminosilicate system.
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Synthesis of MTW-type Zeolites in the Absence of Organic Structure-Directing Agent
Chemistry Letters, 2010Co-Authors: Kenta Iyoki, Yoshihiro Kamimura, Keiji Itabashi, Atsushi Shimojima, Tatsuya OkuboAbstract:The synthesis of MTW-type aluminosilicate zeolites in the absence of organic Structure-Directing Agents (OSDAs) was successfully attained by the addition of calcined ZSM-12 seeds to (Li, Na)-alumin...
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Cooperative Effect of Sodium and Potassium Cations on Synthesis of Ferrierite
Topics in Catalysis, 2008Co-Authors: Yasuhiro Suzuki, Keiji Itabashi, Toru Wakihara, Masaru Ogura, Tatsuya OkuboAbstract:Ferrierite type zeolite can be synthesized without using any organic Structure-Directing Agent from Na- or (Na, K)- or K-aluminosilicate system. (Na, K)-ferrierite is synthesized from wide range of OH/SiO_2 region of the reactant mixture compared with Na- and K-ferrierite. The crystallization process of ferrierite in each system is investigated in detail by X-ray diffraction and Raman spectroscopy. The role of potassium and sodium cations and cooperative effect of two cations in the formation of the framework of ferrierite are elucidated.
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02-P-27 - Synthesis of a new microporous silicate using DABCO-based Structure-Directing Agent
Studies in Surface Science and Catalysis, 2001Co-Authors: Yoshihiro Kubota, Mark E. Davis, Tatsuya Okubo, Jacques Plévert, Takahisa Honda, P. Wagner, Yasutomo Goto, Yoshiaki Fukushima, Yoshihiro SugiAbstract:Publisher Summary This chapter describes the synthesis of a new microporous silicate using 1,4 diazabicyclo[2.2.2]octane (DABCO)-based Structure-Directing Agent (SDA). Results of the synthesis and structure determination are discussed. The behavior of the SDA during synthesis is also presented.
Mark E. Davis - One of the best experts on this subject based on the ideXlab platform.
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Influence of Organic Structure Directing Agent Isomer Distribution on the Synthesis of SSZ-39
Chemistry of Materials, 2015Co-Authors: Michiel Dusselier, Joel E. Schmidt, Roger Moulton, Barry Haymore, Mark Hellums, Mark E. DavisAbstract:The aluminosilicate molecular sieve with the AEI framework topology (SSZ-39) is currently of great interest for use in a number of important applications such as exhaust gas NOx reduction and the methanol-to-olefins reaction. It is likely that advances in the synthesis of this molecular sieve will be needed for applications to proceed. Here, dimethylpiperidine based organic structure directing Agents (OSDAs) are used to prepare SSZ-39, and the influence of diastereo- and structural isomeric mixtures on the synthesis of SSZ-39 is reported. Although differences in the rates of molecular sieve formation as well as preferential isomer incorporation occur, the synthesis of SSZ-39 is possible over a wide range of isomeric mixtures. These findings demonstrate that the synthesis of SSZ-39 can be accomplished with OSDA isomer mixtures that naturally occur from the synthesis of the organic precursors used to prepare the OSDAs.
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The synthesis of aluminophosphate and germanosilicate LTA using a triquaternary structure directing Agent
Microporous and Mesoporous Materials, 2014Co-Authors: Joel E. Schmidt, Stacey I Zones, Mark E. DavisAbstract:The use of triquaternary organic structure directing Agents (OSDAs) for the synthesis of microporous materials is relatively unexplored. Here a triquaternary OSDA prepared by reacting 1,2-dimethylimidazole with 1,3,5-tris(bromomethyl)benzene promotes the formation of LTA in the aluminophosphate or germanosilicate reaction chemistries.
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Structure-Directing Agent location and non-centrosymmetric structure of fluoride-containing zeolite SSZ-55.
Journal of Physical Chemistry B, 2006Co-Authors: Allen W Burton, Russell E. Morris, Richard J. Darton, Mark E. Davis, Song-jong Hwang, Isao Ogino, Stacey I ZonesAbstract:Single crystals of pure silica zeolite SSZ-55 were prepared using the fluoride route. Single-crystal X-ray diffraction at a synchrotron source revealed the framework structure of the material, but the unit cell (orthorhombic a = 12.905(2) A, b = 21.344(4) A, c = 5.1279(10)) is too small to accommodate ordered arrays of the organic Structure-Directing Agent. Molecular modeling was used to simulate the docking of the Structure-Directing Agent in the channels of the material, and this revealed a strong space-filling interaction with a number of possible orientations of the organic cation. The overall non-centrosymmetric structure of the solid (spacegroup C222_1) was confirmed using second harmonic generation experiments.
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A new Structure-Directing Agent for the synthesis of pure-phase ZSM-11
Microporous and Mesoporous Materials, 2001Co-Authors: Patrick M. Piccione, Mark E. DavisAbstract:Abstract A new synthetic procedure for the preparation of pure-phase ZSM-11 (MEL) is reported. Pure-phase ZSM-11 is synthesized at 135 °C using 2,2-diethoxyethyltrimethylammonium as a Structure-Directing Agent (SDA). The effects of the incorporation of boron in the reaction chemistry are also reported. A very high SDA–ZSM-11 specificity is observed since the inclusion of ZSM-5 (MFI) into the synthesis mixture at levels as high as 24 wt.% of the total silica content still leads to the crystallization of ZSM-11.
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02-P-27 - Synthesis of a new microporous silicate using DABCO-based Structure-Directing Agent
Studies in Surface Science and Catalysis, 2001Co-Authors: Yoshihiro Kubota, Mark E. Davis, Tatsuya Okubo, Jacques Plévert, Takahisa Honda, P. Wagner, Yasutomo Goto, Yoshiaki Fukushima, Yoshihiro SugiAbstract:Publisher Summary This chapter describes the synthesis of a new microporous silicate using 1,4 diazabicyclo[2.2.2]octane (DABCO)-based Structure-Directing Agent (SDA). Results of the synthesis and structure determination are discussed. The behavior of the SDA during synthesis is also presented.
Jurgen Caro - One of the best experts on this subject based on the ideXlab platform.
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Facile and reproducible synthesis of ITQ-29 zeolite by using Kryptofix 222 as the structure directing Agent
Microporous and Mesoporous Materials, 2010Co-Authors: Aisheng Huang, Claudia Weidenthaler, Jurgen CaroAbstract:In pioneering papers Corma et al. reported the synthesis of the Al-free zeolite ITQ-29 with LTA topology by using supramolecular self-assembled molecules as the organic structure directing Agent (SDA). However, the SDA used to synthesize ITQ-29 is not commercial and rather difficult to synthesize and purify. Thus the development of a more convenient and more effective method for the synthesis of ITQ-29 is highly desired. Therefore, in this communication we propose a facile and reproducible method to synthesize uniform and well-shaped ITQ-29 crystals by using the crown ether Kryptofix 222 as the SDA.
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Steam-stable hydrophobic ITQ-29 molecular sieve membrane with H2 selectivity prepared by secondary growth using Kryptofix 222 as SDA
Chemical Communications, 2010Co-Authors: Aisheng Huang, Jurgen CaroAbstract:A neutral framework cation-free hydrophobic ITQ-29 molecular sieve membrane with hydrogen selectivity was prepared on porous α-Al2O3 supports by using Kryptofix 222 as organic structure directing Agent through secondary growth method.
