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Amine functionalized K10 montmorillonite: a solid acid-base catalyst for the Knoevenagel condensation reaction
G Bishwa Bidita Varadwaj1, Surjyakanta Rana, K M Parida
1C&MC Department, Institute of Minerals & Materials, Technology, Bhubaneswar-751013, Orissa, India.
Abstract:
Different amine functionalized K10 montmorillonites were hydrothermally fabricated by a simple method of treatment of the neat clay with different amine solutions and used as heterogeneous catalysts towards the Knoevenagel condensation reaction. Catalytic results show that the di-amine functionalized K10 montmorillonite exhibits high efficacy for promoting this reaction at room temperature and in the absence of a solvent. The solid catalyst was characterized using a variety of different techniques; including Fourier transform infrared spectroscopy (FT-IR), nitrogen physisorption measurements, (29)Si CP MAS NMR spectroscopy, NH3-temperature programmed desorption (NH3-TPD), X-ray powder diffraction (XRD), and field emission scanning electron microscopy (FESEM). The catalyst could be recycled and reused for several runs without any loss of inherent catalytic activity.
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