Characterization of Cinchonidine Doped Montmorillonite Supported Noble Metal Catalysts by Thermoanalytical Methods
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The characterization of new cinchonidine doped K-10 montmorillonite supported noble metal catalysts is described. Our aim was the mapping of thermal stability of these new catalytic materials by thermogravimetry (TG), differential thermogravimetry (DTG) and differential thermoanalysis (DTA) methods accompanied by X-ray diffraction (XRD) measurements.
The catalysts were prepared by various methods including conventional, microwave and ultrasonic treatments. They were characterized first by X-ray diffraction to verify the stability of montmorillonite crystal structure during preparation. Then, TG and DTG methods were applied to determine their stability under the experimental conditions usually applied. The main changes observed were the loss of water and the decomposition of the organic modifiers in the higher temperature region. The catalyst showed the best performance were prepared and characterized using microwaves and ultrasonic irradiation in order to get more insight to the effect of preparation methods on their stability. As a consequence, the catalysts were found to be stable and regenerable under 450-500 K, however, higher temperatures resulted in the complete destruction of the catalysts.
- 1.J. A. Rabo, in (I. Guezi, F. Solymosi, P. Tétényi, Eds.) Proc. 10th Int. Congr. Catal., Akadémiai Kiadó, Budapest 1993, p. 1.Google Scholar
- 2.G. Jannes and V. Dubois (Eds.), Chiral Reactions in Heterogeneous Catalysis, Plenum Press, New York, London 1995.Google Scholar
- 4.B. Delmon and J. T. Yates (Eds.), Preparation of Catalysts I–VI, Stud. Surf. Sci. Catal., Vol. 1, 3, 16, 31, 63, 91 (1975–94).Google Scholar
- 5.Y. Iwasawa (Ed.), Tailored Metal Catalysts, D. Riedel, Dordrecht 1986.Google Scholar
- 6.E. Nemecz, Clay Minerals, Akadémiai Kiadó, Budapest 1981.Google Scholar
- 7.M. Balogh and P. László, Organic Chemistry Using Clays, Springer-Verlag, Berlin, Heidelberg 1993.Google Scholar
- 9.B. K. G. Theng, The Chemistry of Clay-Organic Reactions, Halsted Press (a Wiley division), New York 1974.Google Scholar
- 10.T. J. Pinnavaia, Science, 220 (1983) 365.Google Scholar
- 11.P. László, Science, 235 (1987) 1473.Google Scholar
- 23.K. Balázsik, B. Török, G. Szakonyi and M. Bartók, Appl. Catal. A, (in press).Google Scholar
- 24.K. Balázsik, B. Török, G. Szakonyi and M. Bartók, J. Mater. Sci. Lett, (in preparation).Google Scholar
- 25.B. Török, Gy. Szöllösi, M. Rózsa-Tarjáni and M. Bartók, Mol. Cryst. Liquid Cryst., 311 (1998) 289.Google Scholar