Preparation of an MCM-22/Hydrotalcite Framework Composite and Its Catalytic Application

Article abstract of DOI:10.1002/ejic.201601398

A composite material (MAMCM), possessing both a layered cationic MgAl-hydrotalcite (MA-HT) and an anionic MCM-22 framework, was prepared by a simple coprecipitation method. The resulting composite material has features of both MCM-22 and the HT layered framework, as shown by powder XRD, FTIR, ²⁹Si and ²⁷Al-MAS NMR spectroscopy, and SEM studies. Electron microscopy revealed that the layer sheets are arranged in a spherical morphology. The composite material was utilized for the vapor-phase alkylation of toluene. The MAMCM material showed better toluene conversion than MCM-22 and MA-HT materials.

Full text of DOI:10.1002/ejic.201601398

A Journal of
Accepted Article
Title: Preparation of MCM-22 / Hydrotalcite Framework Composite and
Its Catalytic Application
Authors: Ayyamperumal Sakthivel, Thangaraj Baskaran, Jayaraj
Christopher, and Mariyamuthu Mariyaselvakumar
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To be cited as: Eur. J. Inorg. Chem. 10.1002/ejic.201601398
Link to VoR: http://dx.doi.org/10.1002/ejic.201601398

10.1002/ejic.201601398
European Journal of Inorganic Chemistry
European Journal of Inorganic Chemistry
Full paper
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DOI: 10.1002/adsc.2017((220b3cebb4f8a966); accepted
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Preparation of MCM-22 / Hydrotalcite Framework Composite
and Its Catalytic Application
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Thangaraj Baskaran,[a] Jayaraj Christopher,[b] Mariyamuthu
Mariyaselvakumar,[c] Ayyamperumal Sakthivel,* [a,d]
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* a Department of Chemistry, School of Physical Sciences, Riverside Transit Campus, Central University of Kerala,
Padnekkad, Kerala-671 314, India,
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b Indian Oil Corporation Ltd, R&D Centre, Faridabad-121007, India,
c Inorganic Material and Catalysis Division, CSIR-CSMCRI, Bhavnagar-364002, Gujarat, India,
d Department of Chemistry, Inorganic Materials & Catalysis Laboratory, University of Delhi, Delhi-110007, India.
E-mail: sakthivelcuk@cukerala.ac.in / sakthiveldu@gmail.com
URL: http://cukerala.ac.in/index.php?option=com_content&view=article&id=274&Itemid=441&lang=en
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16 ABSTRACT:A composite material (MAMCM) possesing50 and adjust the pore entrance of MCM-22 materials and
17 both layered MgAl-hydrotalcite (HT) and MCM-22 wa5s 1 reduce side reactions such as multi-alkylation and de-
18 prepared by
a
simple co-precipitation method. The52 alkylation.[21-24]
19 resulting composite material has features of both MCM-22
20 and the HT layered framework, as shown by powder XRD,
21 FT-IR, 29Si, 27Al-MAS NMR, and SEM study. Electron
22 microscopy revealed that layer sheets are arranged in a
23 spherical morphology. The composite material was utilized
24 for vapor phase alkylation of toluene. The MAMCM
25 material showed better toluene conversion than MCM-22
26 and MA-HT materials.
27 Keywords: Layered Materials, zeolite, hydrotalcite,
28 catalysts, toluene alkylation
29 Introduction
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Zeolites and modified zeolites have been extensively
31 used for various petrochemical processes[1-5] such as
32 fluidized catalytic cracking,[5] alkylation of aromatics,[6]
33 aromatization of hydrocarbon,[7] isomerization,[7] and also
34 in other fields like drug delivery,[8] bio-sensor,[9]
35 agriculture,[10] and adsorbents[11] etc. MCM-22 is an
36 anionic framework zeolite material constituted of two non-
37 intersecting pore systems with thin-plate morphology and
38 possessing large amount of super-cages on the external
39 packet (Scheme 1).[12-16] Among the various zeolites, ZSM-
40 5 and MCM-22 are medium pore shown as promising
41 shape selective catalysts for the selective preparation of p-
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54 Scheme 1. Schematic representation of MCM-22 structure.
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On other hand, layered hydrotalcite (HT)
57 materials have cationic framework with general
58 formula[M(II)(1‒ x)M(III)x(OH)2]x+[An‒x/n]mH2O,[25-27] yield
59 a variety of tailor made materials and shown as potential
60 catalyst,[28] catalytic supports[29, 30] and adsorbents[31] etc. In
61 the HT materials the interlayer anions are exchangeable,
42 xylene by various processes such as toluene alkylation,
43 disproportionation of toluene and m-xylene isomerization
44 etc.[17-20] In recent decades significant improvement was
45 observed over C8 selectivity on toluene alkylation through
46 different processes such as dealumination, substitution of
47 metal ions, impregnation of oxides and preparation of
48 composites with MCM-22 or ZSM-5 materials etc.[21-24
49 The modification processes cover the external acidic sites
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2 giving rise to elegant intercalation chemistry. In this
63 regards it is worth to mention here that recently, the
1
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