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Sb Hong - One of the best experts on this subject based on the ideXlab platform.
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Zeolite synthesis in the presence of flexible Diquaternary alkylammonium ions (C2H5)(3)N+(CH2)(n)N+(C2H5)(3) with n=3-10 as structure-directing agents
'Elsevier BV', 2019Co-Authors: Sh Lee, Ch Shin, Gj Choi, Tj Park, Is Nam, Han B, Sb HongAbstract:The use of flexible Diquaternary alkylammonium ions (C(2)H(5))(3)N(+)(CH(2))(n)N(+)(C(2)H(5))(3) (Et(6)-Diquat-n with n = 3-10) as structure-directing agents for zeolite synthesis in the presence of alkali metal cation is described. Among the organic structure-directing agents studied here, a considerable diversity in the phase selectivity was observed only for the Et(6)-Diquat-5 ion: this cation can produce five different zeolite structures (i.e., P1, SSZ-16, SUZ-4, ZSM-57, and mordenite), depending on the oxide composition of synthesis mixtures. Analysis of the variable-temperature (1)H CRAMPS NMR spectra obtained from the Et(6)-Diquat-5 molecules in these five zeolites reveals that the host-guest interactions occurring within the respective materials maintain in a manner different from one another even at 160 degreesC at which the zeolite hosts crystallize. (C) 2003 Elsevier Science Inc. All rights reserved.X12
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Diquaternary (CH3)(2)(C2H5)N+(CH2)(n)N+(C2H5)(CH3)(2) and (C2H5)(2)-(CH3)N+(CH2)(n)N+(CH3)(C2H5)(2) ions with n=4-6 as structuredirecting agents in zeolite synthesis
ELSEVIER SCIENCE BV, 2019Co-Authors: Han B, Ch Shin, Is Nam, Sb HongAbstract:The use of flexible, linear Diquaternary alkylarmmonium ions (CH3)(2)(C2H5)N+(CH2)N+-(C2H5)(CH3)(2) (Me4Et2-Diquat-n) and (C2H5)(2)(CH3)N+(CH2)(n)N+(CH3)(C2H5)(2) (Et4Me2-Diquat-n) with n = 4-6 as struture-directing agents in zeolite syntheses is described. Among the ammonium ions studied here, the Et4Me2-diqtiat-4 and Et4Me2-Diquat-6 ions were found to be new structure-directing agents for the crystallization of MCM-47 and SSZ-16, respectively.114sciescopu
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Reinvestigation into the synthesis of zeolites using Diquaternary alkylammonium ions (CH3)(3)N+(CH2)(n)N+(CH3)(3) with n=3-10 as structure-directing agents
'Elsevier BV', 2019Co-Authors: Sh Lee, Ch Shin, Is Nam, Dk Yang, Sd Ahn, Sb HongAbstract:Zeolite syntheses using a series of flexible, linear Diquaternary ammonium ions (CH(3))(3)N(+)(CH(2))(n)N(+)(CH(3))(3) (Me(6)-Diquat-n with n = 3-10) have been reinvestigated in order to explore the effects of inorganic synthesis variables, especially of the type and concentration of alkali cations, on the phase selectivity of the crystallization. Among the ammonium ions studied here, the Me(6)-Diquat-3 ion was found to decompose to form tetramethylammonium ions under the highly basic conditions, leading to the crystallization of zeolite omega, which is a new example of in situ modification of structure-directing agents in zeolite synthesis. Unlike the other seven Diquaternary cations, on the other hand, the Me(6)-Diquat-5 ion exhibited a considerable diversity in the phase selectivitythis cation can crystallize five different zeolite structures (i.e., EU-1, ZSM-48, ZSM-12, MCM-22, and mordenite), depending on the oxide composition of synthesis mixtures. A combination of (1)H-(13)C CP MAS NMR and Raman measurements shows that the host-guest interactions in these five zeolites containing Me(6)-Diquat-5 as a guest molecule are notably different from one another. (C) 2003 Elsevier Inc. All rights reserved.X13
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Reinvestigation into the synthesis of zeolites using Diquaternary alkylammonium ions (CH3)(3)N+(CH2)(n)N+(CH3)(3) with n=3-10 as structure-directing agents
'Elsevier BV', 2019Co-Authors: Sh Lee, Ch Shin, Is Nam, Dk Yang, Sd Ahn, Sb HongAbstract:Zeolite syntheses using a series of flexible, linear Diquaternary ammonium ions (CH(3))(3)N(+)(CH(2))(n)N(+)(CH(3))(3) (Me(6)-Diquat-n with n = 3-10) have been reinvestigated in order to explore the effects of inorganic synthesis variables, especially of the type and concentration of alkali cations, on the phase selectivity of the crystallization. Among the ammonium ions studied here, the Me(6)-Diquat-3 ion was found to decompose to form tetramethylammonium ions under the highly basic conditions, leading to the crystallization of zeolite omega, which is a new example of in situ modification of structure-directing agents in zeolite synthesis. Unlike the other seven Diquaternary cations, on the other hand, the Me(6)-Diquat-5 ion exhibited a considerable diversity in the phase selectivity; this cation can crystallize five different zeolite structures (i.e., EU-1, ZSM-48, ZSM-12, MCM-22, and mordenite), depending on the oxide composition of synthesis mixtures. A combination of (1)H-(13)C CP MAS NMR and Raman measurements shows that the host-guest interactions in these five zeolites containing Me(6)-Diquat-5 as a guest molecule are notably different from one another. (C) 2003 Elsevier Inc. All rights reserved.X1131sciescopu
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Host-Guest Interactions in Zeolites P1, SUZ-4 and ZSM-57 Containing N,N,N,N´,N´,N´-Hexaethylpentane-diammonium Ion as a Guest Molecule
'American Chemical Society (ACS)', 2019Co-Authors: Wc Paik, Ch Shin, Jm Lee, Bj Ahn, Sb HongAbstract:The H-1-C-13 CP MAS NMR and Raman spectra of N,N,N,N',N',N'-hexaethylpentanediammonium (Et-6-Diquat-5) ions encapsulated within P1, SUZ-4, and ZSM-57 zeolites are presented. The Et-6-Diquat-5 molecules occluded are found to adopt distinct molecular conformations in order to fit in the pores of each zeolite host. Computer modeling studies show that encapsulation of Et-6-Diquat-5 in the small-pore zeolite P1 is not energetically favorable. However, a remarkable match between the conformation of guest molecule and the geometry of the host structure is observed for the medium-pore zeolites SUZ-4 and ZSM-57, revealing the existence of organic structure-directing effect. The overall results of this study suggest that conformations available to the flexible, linear organic cation like Et-6-Diquat-5 may differ considerably according to the type and concentration of alkali cations present in the zeolite synthesis mixture, which is a critical factor affecting the phase selectivity of the crystallization. It thus appears that the modification of conformations of flexible organic structure-directing agents by varying the type and concentration of alkali cations may be an area of considerable possibility for finding new zeolite structures.X1132sci
Suk Bong Hong - One of the best experts on this subject based on the ideXlab platform.
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host guest interactions in p1 suz 4 and zsm 57 zeolites containing n n n n n n hexaethylpentanediammonium ion as a guest molecule
Journal of Physical Chemistry B, 2001Co-Authors: Woon Chang Paik, Suk Bong Hong, Chaeho Shin, Jong Myung Lee, And Byoung Joon AhnAbstract:The 1H-13C CP MAS NMR and Raman spectra of N,N,N,N‘,N‘,N‘-hexaethylpentanediammonium (Et6-Diquat-5) ions encapsulated within P1, SUZ-4, and ZSM-57 zeolites are presented. The Et6-Diquat-5 molecules occluded are found to adopt distinct molecular conformations in order to fit in the pores of each zeolite host. Computer modeling studies show that encapsulation of Et6-Diquat-5 in the small-pore zeolite P1 is not energetically favorable. However, a remarkable match between the conformation of guest molecule and the geometry of the host structure is observed for the medium-pore zeolites SUZ-4 and ZSM-57, revealing the existence of organic structure-directing effect. The overall results of this study suggest that conformations available to the flexible, linear organic cation like Et6-Diquat-5 may differ considerably according to the type and concentration of alkali cations present in the zeolite synthesis mixture, which is a critical factor affecting the phase selectivity of the crystallization. It thus appears ...
M Fernandezperez - One of the best experts on this subject based on the ideXlab platform.
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removal of Diquat and deisopropylatrazine from water by montmorillonite ce or zr phosphate crosslinked compounds
Chemosphere, 1999Co-Authors: E Gonzalezpradas, M Villafrancasanchez, F Del Reybueno, M D Urenaamate, M Sociasviciana, M FernandezperezAbstract:Abstract The adsorption of Diquat (1,1′-ethylene-2,2′-dipyridilium dibromide) and one intermediate compound of the degradation of atrazine in water, deisopropylatrazine, on two montmorillonite-(Ce or Zr) phosphate crosslinked compounds from aqueous solution under conditions of varied temperature (288 K and 308 K) has been studied. The experimental adsorption isotherms obtained for Diquat on both adsorbents may be classified as H-type of the Giles classification which suggests that Diquat molecules are strongly adsorbed on the samples. For the deisopropylatrazine, L-type isotherms were obtained for both montmorillonite-(Ce or Zr) phosphate compounds, which suggests a moderate affinity of this metabolite by the active sites of the adsorbents. The increase of temperature from 288 K to 308 K does not clearly affect the adsorption process of Diquat on both adsorbents whereas the deisopropylatrazine adsorption decreases slightly as temperature increases possibly due to a mainly physical process. Fourier transform infrared (FTIR) spectroscopic studies reveal that at the pH generated by the adsorbents, the cationic herbicide interacts to a greater extent with the negative charged surface of the adsorbents than deisopropylatrazine. For both model compounds, the ceriummontmorillonite adsorbent shows the higher capacity of adsorption compared with zirconiummontmorillonite adsorbent.
Ch Shin - One of the best experts on this subject based on the ideXlab platform.
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Zeolite synthesis in the presence of flexible Diquaternary alkylammonium ions (C2H5)(3)N+(CH2)(n)N+(C2H5)(3) with n=3-10 as structure-directing agents
'Elsevier BV', 2019Co-Authors: Sh Lee, Ch Shin, Gj Choi, Tj Park, Is Nam, Han B, Sb HongAbstract:The use of flexible Diquaternary alkylammonium ions (C(2)H(5))(3)N(+)(CH(2))(n)N(+)(C(2)H(5))(3) (Et(6)-Diquat-n with n = 3-10) as structure-directing agents for zeolite synthesis in the presence of alkali metal cation is described. Among the organic structure-directing agents studied here, a considerable diversity in the phase selectivity was observed only for the Et(6)-Diquat-5 ion: this cation can produce five different zeolite structures (i.e., P1, SSZ-16, SUZ-4, ZSM-57, and mordenite), depending on the oxide composition of synthesis mixtures. Analysis of the variable-temperature (1)H CRAMPS NMR spectra obtained from the Et(6)-Diquat-5 molecules in these five zeolites reveals that the host-guest interactions occurring within the respective materials maintain in a manner different from one another even at 160 degreesC at which the zeolite hosts crystallize. (C) 2003 Elsevier Science Inc. All rights reserved.X12
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Diquaternary (CH3)(2)(C2H5)N+(CH2)(n)N+(C2H5)(CH3)(2) and (C2H5)(2)-(CH3)N+(CH2)(n)N+(CH3)(C2H5)(2) ions with n=4-6 as structuredirecting agents in zeolite synthesis
ELSEVIER SCIENCE BV, 2019Co-Authors: Han B, Ch Shin, Is Nam, Sb HongAbstract:The use of flexible, linear Diquaternary alkylarmmonium ions (CH3)(2)(C2H5)N+(CH2)N+-(C2H5)(CH3)(2) (Me4Et2-Diquat-n) and (C2H5)(2)(CH3)N+(CH2)(n)N+(CH3)(C2H5)(2) (Et4Me2-Diquat-n) with n = 4-6 as struture-directing agents in zeolite syntheses is described. Among the ammonium ions studied here, the Et4Me2-diqtiat-4 and Et4Me2-Diquat-6 ions were found to be new structure-directing agents for the crystallization of MCM-47 and SSZ-16, respectively.114sciescopu
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Reinvestigation into the synthesis of zeolites using Diquaternary alkylammonium ions (CH3)(3)N+(CH2)(n)N+(CH3)(3) with n=3-10 as structure-directing agents
'Elsevier BV', 2019Co-Authors: Sh Lee, Ch Shin, Is Nam, Dk Yang, Sd Ahn, Sb HongAbstract:Zeolite syntheses using a series of flexible, linear Diquaternary ammonium ions (CH(3))(3)N(+)(CH(2))(n)N(+)(CH(3))(3) (Me(6)-Diquat-n with n = 3-10) have been reinvestigated in order to explore the effects of inorganic synthesis variables, especially of the type and concentration of alkali cations, on the phase selectivity of the crystallization. Among the ammonium ions studied here, the Me(6)-Diquat-3 ion was found to decompose to form tetramethylammonium ions under the highly basic conditions, leading to the crystallization of zeolite omega, which is a new example of in situ modification of structure-directing agents in zeolite synthesis. Unlike the other seven Diquaternary cations, on the other hand, the Me(6)-Diquat-5 ion exhibited a considerable diversity in the phase selectivitythis cation can crystallize five different zeolite structures (i.e., EU-1, ZSM-48, ZSM-12, MCM-22, and mordenite), depending on the oxide composition of synthesis mixtures. A combination of (1)H-(13)C CP MAS NMR and Raman measurements shows that the host-guest interactions in these five zeolites containing Me(6)-Diquat-5 as a guest molecule are notably different from one another. (C) 2003 Elsevier Inc. All rights reserved.X13
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Reinvestigation into the synthesis of zeolites using Diquaternary alkylammonium ions (CH3)(3)N+(CH2)(n)N+(CH3)(3) with n=3-10 as structure-directing agents
'Elsevier BV', 2019Co-Authors: Sh Lee, Ch Shin, Is Nam, Dk Yang, Sd Ahn, Sb HongAbstract:Zeolite syntheses using a series of flexible, linear Diquaternary ammonium ions (CH(3))(3)N(+)(CH(2))(n)N(+)(CH(3))(3) (Me(6)-Diquat-n with n = 3-10) have been reinvestigated in order to explore the effects of inorganic synthesis variables, especially of the type and concentration of alkali cations, on the phase selectivity of the crystallization. Among the ammonium ions studied here, the Me(6)-Diquat-3 ion was found to decompose to form tetramethylammonium ions under the highly basic conditions, leading to the crystallization of zeolite omega, which is a new example of in situ modification of structure-directing agents in zeolite synthesis. Unlike the other seven Diquaternary cations, on the other hand, the Me(6)-Diquat-5 ion exhibited a considerable diversity in the phase selectivity; this cation can crystallize five different zeolite structures (i.e., EU-1, ZSM-48, ZSM-12, MCM-22, and mordenite), depending on the oxide composition of synthesis mixtures. A combination of (1)H-(13)C CP MAS NMR and Raman measurements shows that the host-guest interactions in these five zeolites containing Me(6)-Diquat-5 as a guest molecule are notably different from one another. (C) 2003 Elsevier Inc. All rights reserved.X1131sciescopu
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Host-Guest Interactions in Zeolites P1, SUZ-4 and ZSM-57 Containing N,N,N,N´,N´,N´-Hexaethylpentane-diammonium Ion as a Guest Molecule
'American Chemical Society (ACS)', 2019Co-Authors: Wc Paik, Ch Shin, Jm Lee, Bj Ahn, Sb HongAbstract:The H-1-C-13 CP MAS NMR and Raman spectra of N,N,N,N',N',N'-hexaethylpentanediammonium (Et-6-Diquat-5) ions encapsulated within P1, SUZ-4, and ZSM-57 zeolites are presented. The Et-6-Diquat-5 molecules occluded are found to adopt distinct molecular conformations in order to fit in the pores of each zeolite host. Computer modeling studies show that encapsulation of Et-6-Diquat-5 in the small-pore zeolite P1 is not energetically favorable. However, a remarkable match between the conformation of guest molecule and the geometry of the host structure is observed for the medium-pore zeolites SUZ-4 and ZSM-57, revealing the existence of organic structure-directing effect. The overall results of this study suggest that conformations available to the flexible, linear organic cation like Et-6-Diquat-5 may differ considerably according to the type and concentration of alkali cations present in the zeolite synthesis mixture, which is a critical factor affecting the phase selectivity of the crystallization. It thus appears that the modification of conformations of flexible organic structure-directing agents by varying the type and concentration of alkali cations may be an area of considerable possibility for finding new zeolite structures.X1132sci
Sh Lee - One of the best experts on this subject based on the ideXlab platform.
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Zeolite synthesis in the presence of flexible Diquaternary alkylammonium ions (C2H5)(3)N+(CH2)(n)N+(C2H5)(3) with n=3-10 as structure-directing agents
'Elsevier BV', 2019Co-Authors: Sh Lee, Ch Shin, Gj Choi, Tj Park, Is Nam, Han B, Sb HongAbstract:The use of flexible Diquaternary alkylammonium ions (C(2)H(5))(3)N(+)(CH(2))(n)N(+)(C(2)H(5))(3) (Et(6)-Diquat-n with n = 3-10) as structure-directing agents for zeolite synthesis in the presence of alkali metal cation is described. Among the organic structure-directing agents studied here, a considerable diversity in the phase selectivity was observed only for the Et(6)-Diquat-5 ion: this cation can produce five different zeolite structures (i.e., P1, SSZ-16, SUZ-4, ZSM-57, and mordenite), depending on the oxide composition of synthesis mixtures. Analysis of the variable-temperature (1)H CRAMPS NMR spectra obtained from the Et(6)-Diquat-5 molecules in these five zeolites reveals that the host-guest interactions occurring within the respective materials maintain in a manner different from one another even at 160 degreesC at which the zeolite hosts crystallize. (C) 2003 Elsevier Science Inc. All rights reserved.X12
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Reinvestigation into the synthesis of zeolites using Diquaternary alkylammonium ions (CH3)(3)N+(CH2)(n)N+(CH3)(3) with n=3-10 as structure-directing agents
'Elsevier BV', 2019Co-Authors: Sh Lee, Ch Shin, Is Nam, Dk Yang, Sd Ahn, Sb HongAbstract:Zeolite syntheses using a series of flexible, linear Diquaternary ammonium ions (CH(3))(3)N(+)(CH(2))(n)N(+)(CH(3))(3) (Me(6)-Diquat-n with n = 3-10) have been reinvestigated in order to explore the effects of inorganic synthesis variables, especially of the type and concentration of alkali cations, on the phase selectivity of the crystallization. Among the ammonium ions studied here, the Me(6)-Diquat-3 ion was found to decompose to form tetramethylammonium ions under the highly basic conditions, leading to the crystallization of zeolite omega, which is a new example of in situ modification of structure-directing agents in zeolite synthesis. Unlike the other seven Diquaternary cations, on the other hand, the Me(6)-Diquat-5 ion exhibited a considerable diversity in the phase selectivitythis cation can crystallize five different zeolite structures (i.e., EU-1, ZSM-48, ZSM-12, MCM-22, and mordenite), depending on the oxide composition of synthesis mixtures. A combination of (1)H-(13)C CP MAS NMR and Raman measurements shows that the host-guest interactions in these five zeolites containing Me(6)-Diquat-5 as a guest molecule are notably different from one another. (C) 2003 Elsevier Inc. All rights reserved.X13
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Reinvestigation into the synthesis of zeolites using Diquaternary alkylammonium ions (CH3)(3)N+(CH2)(n)N+(CH3)(3) with n=3-10 as structure-directing agents
'Elsevier BV', 2019Co-Authors: Sh Lee, Ch Shin, Is Nam, Dk Yang, Sd Ahn, Sb HongAbstract:Zeolite syntheses using a series of flexible, linear Diquaternary ammonium ions (CH(3))(3)N(+)(CH(2))(n)N(+)(CH(3))(3) (Me(6)-Diquat-n with n = 3-10) have been reinvestigated in order to explore the effects of inorganic synthesis variables, especially of the type and concentration of alkali cations, on the phase selectivity of the crystallization. Among the ammonium ions studied here, the Me(6)-Diquat-3 ion was found to decompose to form tetramethylammonium ions under the highly basic conditions, leading to the crystallization of zeolite omega, which is a new example of in situ modification of structure-directing agents in zeolite synthesis. Unlike the other seven Diquaternary cations, on the other hand, the Me(6)-Diquat-5 ion exhibited a considerable diversity in the phase selectivity; this cation can crystallize five different zeolite structures (i.e., EU-1, ZSM-48, ZSM-12, MCM-22, and mordenite), depending on the oxide composition of synthesis mixtures. A combination of (1)H-(13)C CP MAS NMR and Raman measurements shows that the host-guest interactions in these five zeolites containing Me(6)-Diquat-5 as a guest molecule are notably different from one another. (C) 2003 Elsevier Inc. All rights reserved.X1131sciescopu
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Zeolite synthesis in the presence of flexible Diquaternary alkylammonium ions (C2H5)(3)N+(CH2)(n)N+(C2H5)(3) with n=3-10 as structure-directing agents
'Elsevier BV', 2019Co-Authors: Sh Lee, Ch Shin, Gj Choi, Tj Park, Is Nam, Han B, Sb HongAbstract:The use of flexible Diquaternary alkylammonium ions (C(2)H(5))(3)N(+)(CH(2))(n)N(+)(C(2)H(5))(3) (Et(6)-Diquat-n with n = 3-10) as structure-directing agents for zeolite synthesis in the presence of alkali metal cation is described. Among the organic structure-directing agents studied here, a considerable diversity in the phase selectivity was observed only for the Et(6)-Diquat-5 ion: this cation can produce five different zeolite structures (i.e., P1, SSZ-16, SUZ-4, ZSM-57, and mordenite), depending on the oxide composition of synthesis mixtures. Analysis of the variable-temperature (1)H CRAMPS NMR spectra obtained from the Et(6)-Diquat-5 molecules in these five zeolites reveals that the host-guest interactions occurring within the respective materials maintain in a manner different from one another even at 160 degreesC at which the zeolite hosts crystallize. (C) 2003 Elsevier Science Inc. All rights reserved.X1129sciescopu