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Microwave-activated p-TSA dealuminated montmorillonite – a new material with improved catalytic activity

  • S. Ramesh (a1), Y. S. Bhat (a1) and B. S. Jai Prakash (a2)

Abstract

We report a montmorillonite material with enhanced surface area but with very little alteration in cation exchange capacity (CEC) upon dealumination with para toluene sulphonic acid (p-TSA). The new material shows higher catalytic activity in comparison with mineral-acid-treated clay. Montmorillonite clay was treated with p-TSA for 10 minutes under microwave irradiation. The resulting clay was characterized by CEC, X-ray diffraction (XRD), BET analysis, Fourier transform infrared spectroscopy (FT-IR), temperature programmed desorption (TPD) of ammonia and cyclic voltametry (CV) techniques. XRD patterns show an unchanged structure of pristine matrix after the acid action. BET analysis revealed an increase in the surface area and pore volume on p-TSA treatment, indicating formation of voids in the octahedral layer which suggests dealumination. Nitrogen adsorption-desorption curves showed the creation of new micro porous regions, possibly in the octahedral sheets. In contrast to mineral acid treatment, p-TSA treated clay samples showed similar CEC which shows the absence of dissolution of isomorphously substituted Mg and Fe ions present in the octahedral layer. CV studies confirm the formation of an Al-p-TSA complex, suggesting dissolution of aluminium octahedral sheets. The complex subsequently hydrolyses, replacing interlayer cations with Al3+ ions. Similar treatment with mineral acid resulted in clay with enhanced surface area but with reduced CEC, evidently due to the removal of isomorphously substituted Fe and Mg. Further, the p-TSA treated clays showed relatively higher esterification activity under solvent-free microwave irradiation. The p-TSA treated clay retained its activity even after three subsequent runs and thus can be exploited for practical applications.

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Presented at the Euroclay 2011 Conference at Antalya, Turkey

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Achyut Panda, K., Mishra, B.G., Mishra, D. K. & Singh, R. K. (2010) Effect of sulphuric acid treatment on the physico-chemical properties of kaolin clay. Colloids and Surfaces A: Physicochemical and Engineering Aspects, 363, 98–104.
Anil, S.G., Nadim, S.S., Gowda, K.K., Vishnu, H.D., Thottappilli, R. & Ashutosh, V. B. (2000) Clay catalyzed conversion of isatoic anhydride to 2-(oaminophenyl) oxazolines. Journal of the Chemical Society, Perkin Transactions, 1, 999–1001.
Belver, C., Munoz, M.A.B. & Vicente M. A (2002) Chemical activation of a kaolinite under acid and alkaline condition. Chemistry of Materials, 14, 2033–2043.
Breen, C. & Moronta, J. (2001) Influence of exchange cations and layer charge on the isomerisation of apinene over SWy-2, SAz-1 and Sap-Ca. Clay Minerals, 36, 467–472.
Breen, C.J., Madejova, J. & Komadel, P. (1995) Characterisation of moderately acid-treated, sizefractionated montmorillonites using IR and MAS NMR spectroscopy and thermal analysis. Journal of Materials Chemistry, 5, 469–474.
Chandrashekara, B.M., Jai Prakash, B. S. & Bhat, Y. S. (2011) Dealumination of beta zeolites under microwave irradiation. ACS Catalysis, 1, 193–199.
Emeis, C.A. (1963) Determination of integrated molar extension coefficient for infrared absorption bands of pyridine adsorbed on solid acid catalysts. Journal of Catalysis, 141, 347–354.
Frankel, M. (1974) Surface acidity of montmorillonites. Clays and Clay Minerals, 22, 435–441.
Hart, M. P. & Brown, D. R. (2004) Surface acidities and catalytic activities of acid-activated clays. Journal of Molecular Catalysis A, 212, 315–321.
Jankovic, L. & Komadel, P. (2003) Metal ion exchanged montmorillonite catalysed protection of aromatic aldehydes with AC2O. Journal of Catalysis, 218, 227–233.
Komadel, P., Schmidit, D., Madejova, J. & Cicil, B. (1990) Correlation of catalytic activity with infra-red, 29Si MAS NMR and acidity data for HCl-treated fine fractions of montmorillonite. Applied Clay Science, 5, 113–122.
Komadel, P., Madejova, J., Janek, M., Gates, W.P., Kirkpatrick, R. J. & Stucki, J. W. (1996) Chemically modified smectites, Clays and Clay Minerals, 44, 228–236.
Korichi, S., Elias, A. & Mefti, A. (2009) Characterisation of smectite after acid activation with microwave irradiation. Applied Clay Science, 42, 428–432.
Kumar, P., Jasra, R. V. & Bhat, T. S.G. (1995) Evolution of porosity and surface acidity in montmorillonite clay on acid activation. Industrial Engineering Chemistry Research, 34, 1440–1448.
Mortland, M. M. & Raman, K. V. (1968) Surface acidity of smectites in relation to hydration, exchangeable cation, and structure. Clays and Clay Minerals, 16, 393–398.
Nagendrappa, G. (2011) Organic synthesis using clay and clay supported reagents. Applied Clay Science, 53, 106–138.
Parry, E. (1963) An infrared study of pyridine adsorbed on acidic solids, characterization of surface acidity. Journal of Catalysis, 2, 371–379.
Ramesh, S., Jai Prakash, B. S. & Bhat, Y. S. (2009) Enhancing Brønsted acid site activity of ion exchanged montmorillonite by microwave irradiation for ester synthesis. Applied Clay Science, 48, 159–163.
Ramesh, S., Jai Prakash, B. S. & Bhat, Y. S. (2011) Highly active and selective C-alkylation of p-cresol with cyclohexanol using p-TSA treated clays under solvent free microwave irradiation. Applied Catalysis A, 413-414, 157–162.
Reddy, C.R., Vijayakumar, B., Iyengar, P., Nagendrappa, G. & Jai Prakash, B.S. (2004) Synthesis of pcresylphenylacetate using aluminium exchanged montmorillonite clay catalyst. Journal of Molecular Catalysis A, 223, 117–122.
Reddy, C.R., Bhat, Y.S., Nagendrappa, G. & Jai Prakash, B.S. (2009) Brønsted and Lewis acidity of modified montmorillonite clay catalysts determined by FT-IR spectroscopy. Catalysis Today, 141, 157–160.
Rhodes, C. N. & Brown, D. R. (1992) Structural characterisation and optimisation of acid-treated montmorillonite and high-porosity silica supports for ZnCl2 alkylation catalysts. Journal of the Chemical Society, Faraday Transactions, 88, 2269–2274.
Sandel, E.B. (1959) Colorimetric Determination of Traces of Metals, 3rd edition. Interscience Publishers, New York.
Selvaraj, S., Mohan, B.V., Krishna, K. N. & Jai Prakash, B.S. (1996) Pillaring of smectites using an aluminium oligomer: A study of pillar density and thermal stability. Applied Clay Science, 10, 439–450.
Steudel, A., Batenburg, L.F., Fischer, H.R., Weidler, P. G. & Emmerich, K. (2009) Alteration of swelling clay minerals by acid activation. Applied Clay Science, 44, 105–115.
Yadav, G. D. & George, G. (2008) Single step synthesis of 4- hydroxybenzophenone via esterification and Fries rearrangement: novelty of cesium substituted heteropoly acid supported on clay. Journal of Molecular Catalysis A, 292, 54–61.
Zhou, C.H (2011) An overview on strategies towards clay-based designer catalysts for green and sustainable catalysis. Applied Clay Science, 53, 87–96.

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