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Suman K Jana - One of the best experts on this subject based on the ideXlab platform.
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Recent developments of heterogeneous solid catalysts for liquid-phase Friedel–Crafts type Benzylation reaction
Catalysis Surveys from Asia, 2005Co-Authors: Suman K JanaAbstract:Liquid-phase Friedel–Crafts type Benzylation of aromatics has been effected traditionally with catalysis by homogeneous protonic acid or Lewis acid. However, heterogeneous catalysts have the advantages, compared to their homogeneous counterparts, of facile recovering and recycling. This short article describes the recent advances in the liquid-phase Friedel–Crafts type Benzylation by benzyl chloride of aromatics over redox metal: gallium (Ga), indium (In) and thallium (Tl) containing novel heterogeneous solid catalysts. Unlike conventional acidic catalyst, the Benzylation activity of the Ga-, In- or Tl-based solids does not depend solely on their acidic properties, even present; these solids in their non-acidic or basic form also shows high Benzylation activity. The catalytic activity order of Ga, In and Tl containing solid catalysts supported on chemically similar inert catalyst carrier is as follows: thallium/support > indium/support > gallium/support, which is quite similar to their redox potential values indicating the role of redox function in the Benzylation process. A plausible reaction mechanism for the Benzylation reaction over these catalysts is proposed. These heterogeneous solids are highly efficient for the Friedel–Crafts type Benzylation, even in the presence of moisture, than the conventional strongly acidic solid acid catalysts.
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Benzylation of benzene by benzyl chloride over fe modified zsm 5 and h β zeolites and fe2o3 or fecl3 deposited on micro meso and macro porous supports
Microporous and Mesoporous Materials, 2002Co-Authors: Vasant R Choudhary, Suman K Jana, Ajit S MammanAbstract:Abstract A number of Fe-containing solid catalysts, such as Fe-modified ZSM-5 type zeolites (Fe 2 O 3 /H-ZSM-5, SO 4 2− /Fe 2 O 3 /H-ZSM-5, H-FeMFI and H-FeAlMFI), Fe-modified H-β zeolites (Fe 2 O 3 /H-β and SO 4 2− /Fe 2 O 3 /H-β), Fe 2 O 3 supported on meso-porous Si-MCM-41, silica gel or macro-porous silica–alumina commercial catalyst carrier (SA-5205), and FeCl 3 impregnated on 13X zeolite, Si-MCM-41, silica gel or commercial clays––montmorillonite K10 (Mont K10) or kaolin, have been compared for their performance in the Benzylation of benzene by benzyl chloride (80 °C). Among these catalysts, the Fe 2 O 3 /H-β (or H-ZSM-5) and FeCl 3 /Mont K10 (or Si-MCM-41) are found to be highly promising ones for the Benzylation, even in the presence of moisture. These catalysts can also be reused in the reaction but with reduced activity. No direct relationship is observed between the acidity (measured in terms of ammonia chemisorbed at 50 or 200 °C) and the Benzylation activity of the catalysts. The Benzylation activity is controlled mainly by the redox properties of the catalyst. The selectivity for diphenyl methane in the Benzylation was found to vary from catalyst to catalyst.
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Benzylation of benzene and substituted benzenes by benzyl chloride over incl3 gacl3 fecl3 and zncl2 supported on clays and si mcm 41
Journal of Molecular Catalysis A-chemical, 2002Co-Authors: Vasant R Choudhary, Suman K JanaAbstract:Abstract Liquid phase Benzylation of benzene by benzyl chloride to diphenyl methane over InCl3, GaCl3, FeCl3 and ZnCl2 supported on commercial clays (viz. Montmorillonite-K10, Montmorillonite-KSF and Kaolin) or on high silica mesoporous MCM-41 (at 60, 70 and 80 °C) has been investigated. The supported InCl3, GaCl3 and FeCl3 showed high activity for the Benzylation of benzene. The redox function created due to the impregnation of the clays or Si-MCM-41 by InCl3, GaCl3, FeCl3 or ZnCl2 seems to play a very important role in the Benzylation process. Among the catalysts, the InCl3/Mont.-K10 showed both high activity and high selectivity for the Benzylation. The activity of this catalyst for the Benzylation of different aromatic compounds is in the following order: benzene>toluene>mesitylene>anisole. The InCl3 (or GaCl3)/Mont.-K10 (or Si-MCM-41) catalyst showed high benzene Benzylation activity even in the presence of moisture in the reaction mixture. The catalyst can also be reused in the Benzylation for several times. Kinetics of the benzene Benzylation (using excess of benzene) over the supported metal chloride catalysts have also been thoroughly investigated. A plausible reaction mechanism for the Benzylation over the supported metal chloride catalysts is proposed.
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Benzylation of benzene by benzyl chloride over fe zn ga and in modified zsm 5 type zeolite catalysts
Applied Catalysis A-general, 2002Co-Authors: Vasant R Choudhary, Suman K JanaAbstract:Liquid phase Benzylation of benzene by benzyl chloride to diphenylmethane over H-ZSM-5, H-gallosilicate (MFI), H-galloaluminosilicate (MFI), H-ferrosilicate (MFI), H-ferroaluminosilicate (MFI), Fe 2 O 3 /H-ZSM-5, ZnO/H-ZSM-5, Ga 2 O 3 /H-ZSM-5 and In 2 O 3 /H-ZSM-5 zeolites (at 60 and 80°C) has been investigated. A complete or partial substitution of Al in H-ZSM-5 zeolite by Fe or Ga or an impregnation of the zeolite by Fe 2 O 3 , ZnO, Ga 2 O 3 or In 2 O 3 makes the zeolite highly active in the Benzylation process. The redox function created due to the modification of the H-ZSM-5 zeolite by Fe, Zn, Ga or In seems to play very important role in the Benzylation process. However, all these catalysts show a significant induction period for the reaction. The Ga 2 O 3 /H-ZSM-5 catalyst showed high benzene Benzylation activity even in the presence of moisture in the catalyst and/or in the substrate. However, the reaction induction period is increased markedly with increasing the moisture and it is reduced by removing the moisture from the catalyst by refluxing with moisture-free benzene. It is also reduced by the HCl gas pretreatment to the catalyst before the Benzylation reaction. The Ga 2 O 3 /H-ZSM-5 and In 2 O 3 /H-ZSM-5 catalysts showed excellent reusability in the benzene Benzylation. Kinetics of the benzene Benzylation (using an excess of benzene) over the H-GaMFI, H-GaAlMFI, H-FeMFI, Ga 2 O 3 /H-ZSM-5 and In 2 O 3 /H-ZSM-5 catalysts have also been thoroughly investigated. A plausible reaction mechanism for the reaction over the modified ZSM-5 zeolite catalysts is proposed.
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alkylation of benzene by benzyl chloride over h zsm 5 zeolite with its framework al completely or partially substituted by fe or ga
Catalysis Letters, 1999Co-Authors: Vasant R Choudhary, Suman K Jana, B P KiranAbstract:Liquid-phase Benzylation of benzene by benzyl chloride to diphenylmethane over H-ZSM-5, H-gallosilicate(MFI), H-galloaluminosilicate(MFI), H-ferrosilicate(MFI) and H-ferroaluminosilicate(MFI) zeolites at 80°C has been investigated. A complete or partial substitution of Al in H-ZSM-5 zeolite by Fe or Ga results in a drastic increase in the catalytic activity of the zeolite in the Benzylation process. The redox function of the zeolite is relatively more important than its acid function in the Benzylation process.
Vasant R Choudhary - One of the best experts on this subject based on the ideXlab platform.
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Highly active and reusable catalyst from Fe-Mg-hydrotalcite anionic clay for Friedel-Crafts type Benzylation reactions
Journal of Chemical Sciences, 2005Co-Authors: Vasant R Choudhary, Pankaj A. ChoudhariAbstract:Fe-Mg-hydrotalcite (Mg/Fe = 3) anionic clay with or without calcination (at 200–800‡C) has been used for the Benzylation of toluene and other aromatic compounds by benzyl chloride. Hydrotalcite before and after its calcination was characterized for surface area, crystalline phases and basicity. Both the hydrotalcite, particularly after its use in the Benzylation reaction, and the catalyst derived from it by its calcination at 200–800‡C show high catalytic activity for the Benzylation of toluene and other aromatic compounds. The catalytically active species present in the catalyst in its most active form are the chlorides and oxides of iron on the catalyst surface.
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Benzylation of benzene by benzyl chloride over fe modified zsm 5 and h β zeolites and fe2o3 or fecl3 deposited on micro meso and macro porous supports
Microporous and Mesoporous Materials, 2002Co-Authors: Vasant R Choudhary, Suman K Jana, Ajit S MammanAbstract:Abstract A number of Fe-containing solid catalysts, such as Fe-modified ZSM-5 type zeolites (Fe 2 O 3 /H-ZSM-5, SO 4 2− /Fe 2 O 3 /H-ZSM-5, H-FeMFI and H-FeAlMFI), Fe-modified H-β zeolites (Fe 2 O 3 /H-β and SO 4 2− /Fe 2 O 3 /H-β), Fe 2 O 3 supported on meso-porous Si-MCM-41, silica gel or macro-porous silica–alumina commercial catalyst carrier (SA-5205), and FeCl 3 impregnated on 13X zeolite, Si-MCM-41, silica gel or commercial clays––montmorillonite K10 (Mont K10) or kaolin, have been compared for their performance in the Benzylation of benzene by benzyl chloride (80 °C). Among these catalysts, the Fe 2 O 3 /H-β (or H-ZSM-5) and FeCl 3 /Mont K10 (or Si-MCM-41) are found to be highly promising ones for the Benzylation, even in the presence of moisture. These catalysts can also be reused in the reaction but with reduced activity. No direct relationship is observed between the acidity (measured in terms of ammonia chemisorbed at 50 or 200 °C) and the Benzylation activity of the catalysts. The Benzylation activity is controlled mainly by the redox properties of the catalyst. The selectivity for diphenyl methane in the Benzylation was found to vary from catalyst to catalyst.
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Benzylation of benzene and substituted benzenes by benzyl chloride over incl3 gacl3 fecl3 and zncl2 supported on clays and si mcm 41
Journal of Molecular Catalysis A-chemical, 2002Co-Authors: Vasant R Choudhary, Suman K JanaAbstract:Abstract Liquid phase Benzylation of benzene by benzyl chloride to diphenyl methane over InCl3, GaCl3, FeCl3 and ZnCl2 supported on commercial clays (viz. Montmorillonite-K10, Montmorillonite-KSF and Kaolin) or on high silica mesoporous MCM-41 (at 60, 70 and 80 °C) has been investigated. The supported InCl3, GaCl3 and FeCl3 showed high activity for the Benzylation of benzene. The redox function created due to the impregnation of the clays or Si-MCM-41 by InCl3, GaCl3, FeCl3 or ZnCl2 seems to play a very important role in the Benzylation process. Among the catalysts, the InCl3/Mont.-K10 showed both high activity and high selectivity for the Benzylation. The activity of this catalyst for the Benzylation of different aromatic compounds is in the following order: benzene>toluene>mesitylene>anisole. The InCl3 (or GaCl3)/Mont.-K10 (or Si-MCM-41) catalyst showed high benzene Benzylation activity even in the presence of moisture in the reaction mixture. The catalyst can also be reused in the Benzylation for several times. Kinetics of the benzene Benzylation (using excess of benzene) over the supported metal chloride catalysts have also been thoroughly investigated. A plausible reaction mechanism for the Benzylation over the supported metal chloride catalysts is proposed.
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Benzylation of benzene by benzyl chloride over fe zn ga and in modified zsm 5 type zeolite catalysts
Applied Catalysis A-general, 2002Co-Authors: Vasant R Choudhary, Suman K JanaAbstract:Liquid phase Benzylation of benzene by benzyl chloride to diphenylmethane over H-ZSM-5, H-gallosilicate (MFI), H-galloaluminosilicate (MFI), H-ferrosilicate (MFI), H-ferroaluminosilicate (MFI), Fe 2 O 3 /H-ZSM-5, ZnO/H-ZSM-5, Ga 2 O 3 /H-ZSM-5 and In 2 O 3 /H-ZSM-5 zeolites (at 60 and 80°C) has been investigated. A complete or partial substitution of Al in H-ZSM-5 zeolite by Fe or Ga or an impregnation of the zeolite by Fe 2 O 3 , ZnO, Ga 2 O 3 or In 2 O 3 makes the zeolite highly active in the Benzylation process. The redox function created due to the modification of the H-ZSM-5 zeolite by Fe, Zn, Ga or In seems to play very important role in the Benzylation process. However, all these catalysts show a significant induction period for the reaction. The Ga 2 O 3 /H-ZSM-5 catalyst showed high benzene Benzylation activity even in the presence of moisture in the catalyst and/or in the substrate. However, the reaction induction period is increased markedly with increasing the moisture and it is reduced by removing the moisture from the catalyst by refluxing with moisture-free benzene. It is also reduced by the HCl gas pretreatment to the catalyst before the Benzylation reaction. The Ga 2 O 3 /H-ZSM-5 and In 2 O 3 /H-ZSM-5 catalysts showed excellent reusability in the benzene Benzylation. Kinetics of the benzene Benzylation (using an excess of benzene) over the H-GaMFI, H-GaAlMFI, H-FeMFI, Ga 2 O 3 /H-ZSM-5 and In 2 O 3 /H-ZSM-5 catalysts have also been thoroughly investigated. A plausible reaction mechanism for the reaction over the modified ZSM-5 zeolite catalysts is proposed.
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alkylation of benzene by benzyl chloride over h zsm 5 zeolite with its framework al completely or partially substituted by fe or ga
Catalysis Letters, 1999Co-Authors: Vasant R Choudhary, Suman K Jana, B P KiranAbstract:Liquid-phase Benzylation of benzene by benzyl chloride to diphenylmethane over H-ZSM-5, H-gallosilicate(MFI), H-galloaluminosilicate(MFI), H-ferrosilicate(MFI) and H-ferroaluminosilicate(MFI) zeolites at 80°C has been investigated. A complete or partial substitution of Al in H-ZSM-5 zeolite by Fe or Ga results in a drastic increase in the catalytic activity of the zeolite in the Benzylation process. The redox function of the zeolite is relatively more important than its acid function in the Benzylation process.
O Cherifi - One of the best experts on this subject based on the ideXlab platform.
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Catalytic properties of the Cr-HMS materials in the Benzylation of benzene with benzyl chloride
Kinetics and Catalysis, 2011Co-Authors: Khaldoun Bachari, A. Touileb, N. Tahir, Adel Saadi, D. Halliche, O CherifiAbstract:A series of chromium-containing mesoporous silicas with different Cr contents were prepared and characterized with chemical analysis, N2 adsorption measurements (BET equation and BJH theory), X-ray diffraction, diffuse reflectance UV-visible and H2-temperature programmed reduction techniques. Excellent results in Benzylation of benzene and substituted benzenes employing benzyl chloride as the alkylating agent were obtained. The mesoporous chromium-containing materials showed both high activity and high selectivity for Benzylation of benzene. The activity of these catalysts for the Benzylation of different aromatic compounds is in the following order: benzene > toluene > p-xylene > anisole. Kinetics of the benzene Benzylation over these catalysts has also been investigated.
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Catalytic properties of antimony-SBA-15 materials in the Benzylation of aromatics reactions
Kinetics and Catalysis, 2009Co-Authors: Khaldoun Bachari, A. Touileb, O CherifiAbstract:Antimony-containing mesoporous SBA-15 with different Si/Sb ratio has been synthesized using a post-treatment procedure with an aqueous solution of SbCl3 and characterized by elemental analysis, XRD method, N2 adsorption measurements (BET and BJH theory) and FTIR spectroscopy. The Benzylation of aromatics by benzyl chloride has been investigated over these solids. Indeed, the antimony-containing mesoporous SBA-15 showed both high activity and high selectivity for this reaction. More interesting is the observation that Sb-SBA-15 (35) catalyst is active and selective for large molecules like naphthenic compounds such as 2-methylnaphthalene and it can also be reused in the Benzylation of benzene for several times. Kinetics of the benzene Benzylation over these catalysts have also been investigated.
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Study of the Benzylation of aromatics over Mg-Cr-hydrotalcite catalysts
Studies in Surface Science and Catalysis, 2008Co-Authors: Nadia Tahir, O Cherifi, Adel Saadi, D. Halliche, Z Abdelssadek, Khaldoun BachariAbstract:Abstract The Benzylation of aromatics by benzyl chloride over Mg-Cr-LDH (Mg/Cr = 2) clay without or with calcination (at 473–1073K) has been investigated. The catalyst derived from the hydrotalcite by its calcination at 473–1073K show high catalytic activity for the Benzylation of aromatics. The catalytically active species present in the catalyst in its most active form are the oxides of chromium on the catalyst surface. The activity of the catalyst calcined at 1073K for the Benzylation of different aromatic compounds is in the following order: benzene > toluene > p -xylene > anisole.
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mg fe hydrotalcite as catalyst for the Benzylation of benzene and other aromatics by benzyl chloride reactions
Surface and Interface Analysis, 2008Co-Authors: N. Tahir, O Cherifi, D. Halliche, Z Abdelssadek, S Saadi, R Chebout, Khaldoun BachariAbstract:The Benzylation of benzene and substituted benzenes reaction employing benzyl chloride as the alkylating agent over Mg-Fe-LDH (Mg/Fe = 2) clay without or with calcination (at 473–1073 K) has been investigated. Hydrotalcite before and after its calcination was characterized for surface area and crystalline phases. The catalyst derived from the hydrotalcite by its calcination at 473–1073 K show high catalytic activity for the Benzylation of benzene and other aromatic compounds. The catalytically active species present in the catalyst in its most active form are the oxides of iron on the catalyst surface. The activity of the catalyst calcined at 1073 K for the Benzylation of different aromatic compounds is in the following order: benzene> toluene> p-xylene> anisole. Kinetics of the benzene Benzylation over these catalysts have also been investigated. Copyright © 2008 John Wiley & Sons, Ltd.
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Zinc-containing mesoporous silicas as a catalyst for the Benzylation of benzene and other aromatics by benzyl chloride
Kinetics and Catalysis, 2007Co-Authors: Khaldoun Bachari, O CherifiAbstract:The Benzylation of benzene and the substituted benzenes reaction employing benzyl chloride as the alkylating agent over a series of zinc-containing mesoporous silicas with different Zn contents have been investigated. These materials (Zn-HMS-n) have been characterized by chemical analysis, BET, and XRD. The mesoporous zinc-containing materials showed both high activity and high selectivity for Benzylation of benzene. The activity of these catalysts for the Benzylation of different aromatic compounds is in the following order: benzene > toluene > p-xylene > anisole. The kinetics of the benzene Benzylation over these catalysts has also been investigated.
Isao Azumaya - One of the best experts on this subject based on the ideXlab platform.
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chemoselective Benzylation of unprotected anthranilic acids with benzhydryl alcohols by water soluble au iii tppms in water
ChemInform, 2013Co-Authors: Hidemasa Hikawa, Hideharu Suzuki, Yuusaku Yokoyama, Isao AzumayaAbstract:The novel and efficient Benzylation method is applicable to a number of anthranilic acids and various alcohols.
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chemoselective Benzylation of unprotected anthranilic acids with benzhydryl alcohols by water soluble au iii tppms in water
Journal of Organic Chemistry, 2013Co-Authors: Hidemasa Hikawa, Hideharu Suzuki, Yuusaku Yokoyama, Isao AzumayaAbstract:A novel and efficient method for the Benzylation of unprotected anthranilic acids with benzhydryl alcohols using water-soluble Au(III)/TPPMS in water is developed. Water plays an important role in our catalytic system. This new protocol could be used for not only N-Benzylation, but also chemoselective C-Benzylation by the Friedel–Crafts reaction.
Khaldoun Bachari - One of the best experts on this subject based on the ideXlab platform.
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Catalytic properties of the Cr-HMS materials in the Benzylation of benzene with benzyl chloride
Kinetics and Catalysis, 2011Co-Authors: Khaldoun Bachari, A. Touileb, N. Tahir, Adel Saadi, D. Halliche, O CherifiAbstract:A series of chromium-containing mesoporous silicas with different Cr contents were prepared and characterized with chemical analysis, N2 adsorption measurements (BET equation and BJH theory), X-ray diffraction, diffuse reflectance UV-visible and H2-temperature programmed reduction techniques. Excellent results in Benzylation of benzene and substituted benzenes employing benzyl chloride as the alkylating agent were obtained. The mesoporous chromium-containing materials showed both high activity and high selectivity for Benzylation of benzene. The activity of these catalysts for the Benzylation of different aromatic compounds is in the following order: benzene > toluene > p-xylene > anisole. Kinetics of the benzene Benzylation over these catalysts has also been investigated.
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Catalytic properties of antimony-SBA-15 materials in the Benzylation of aromatics reactions
Kinetics and Catalysis, 2009Co-Authors: Khaldoun Bachari, A. Touileb, O CherifiAbstract:Antimony-containing mesoporous SBA-15 with different Si/Sb ratio has been synthesized using a post-treatment procedure with an aqueous solution of SbCl3 and characterized by elemental analysis, XRD method, N2 adsorption measurements (BET and BJH theory) and FTIR spectroscopy. The Benzylation of aromatics by benzyl chloride has been investigated over these solids. Indeed, the antimony-containing mesoporous SBA-15 showed both high activity and high selectivity for this reaction. More interesting is the observation that Sb-SBA-15 (35) catalyst is active and selective for large molecules like naphthenic compounds such as 2-methylnaphthalene and it can also be reused in the Benzylation of benzene for several times. Kinetics of the benzene Benzylation over these catalysts have also been investigated.
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Study of the Benzylation of aromatics over Mg-Cr-hydrotalcite catalysts
Studies in Surface Science and Catalysis, 2008Co-Authors: Nadia Tahir, O Cherifi, Adel Saadi, D. Halliche, Z Abdelssadek, Khaldoun BachariAbstract:Abstract The Benzylation of aromatics by benzyl chloride over Mg-Cr-LDH (Mg/Cr = 2) clay without or with calcination (at 473–1073K) has been investigated. The catalyst derived from the hydrotalcite by its calcination at 473–1073K show high catalytic activity for the Benzylation of aromatics. The catalytically active species present in the catalyst in its most active form are the oxides of chromium on the catalyst surface. The activity of the catalyst calcined at 1073K for the Benzylation of different aromatic compounds is in the following order: benzene > toluene > p -xylene > anisole.
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mg fe hydrotalcite as catalyst for the Benzylation of benzene and other aromatics by benzyl chloride reactions
Surface and Interface Analysis, 2008Co-Authors: N. Tahir, O Cherifi, D. Halliche, Z Abdelssadek, S Saadi, R Chebout, Khaldoun BachariAbstract:The Benzylation of benzene and substituted benzenes reaction employing benzyl chloride as the alkylating agent over Mg-Fe-LDH (Mg/Fe = 2) clay without or with calcination (at 473–1073 K) has been investigated. Hydrotalcite before and after its calcination was characterized for surface area and crystalline phases. The catalyst derived from the hydrotalcite by its calcination at 473–1073 K show high catalytic activity for the Benzylation of benzene and other aromatic compounds. The catalytically active species present in the catalyst in its most active form are the oxides of iron on the catalyst surface. The activity of the catalyst calcined at 1073 K for the Benzylation of different aromatic compounds is in the following order: benzene> toluene> p-xylene> anisole. Kinetics of the benzene Benzylation over these catalysts have also been investigated. Copyright © 2008 John Wiley & Sons, Ltd.
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alkylation of benzene and other aromatics by benzyl chloride over iron containing aluminophosphate molecular sieves
Journal of Molecular Catalysis A-chemical, 2007Co-Authors: H Hentit, B Benaichouba, Khaldoun Bachari, M S Ouali, M Womes, J C JumasAbstract:Abstract Iron-containing aluminophosphate molecular sieves were synthesized in AEL and AFI structure types by static hydrothermal crystallization. These materials have been characterized by elemental analysis, X-ray diffraction, scanning electron microscopy, N2 adsorption–desorption, temperature programmed desorption of ammonia (NH3-TPD), and 57Fe Mossbauer spectroscopy. Alkylation of benzene and other aromatics by benzyl chloride has been investigated over these solids. Indeed, the iron containing microporous aluminophosphates showed both high activity and high selectivity for this reaction. The activity of these catalysts for the Benzylation of different aromatic compounds is in the following order: benzene > toluene > p-xylene > anisole. More interesting is the observation that this catalyst can be reused in the Benzylation of benzene for several times. Kinetics of the benzene Benzylation over these catalysts has also been investigated.
