The Influence of Porous Structure and Acid-Base Properties of Active Aluminium Oxide on its Catalytic Activity in the Dehydratation of О±-Phenylethanol
A. A. Lamberov1, R. G.В Romanova2, I. G.В Shmelev2, E. Yu.В Sitnikova1 and S. R.В Egorova2
1Kazan' Chemical Research Institute,
Sibirskiy trakt 27, Kazan' 420029 (Russia), E-mail: segorova@rambler.ru
2Kazan' State Technological University,
Ul. K.В Marxa 68, Kazan' 420015 (Russia), E-mail: rrg@kstu.ru
Abstract
The influence of porous structure and surface acid-base properties of γ-Al2O3, prepared by means of aluminate-nitrate and electrochemical methods, on its catalytic activity in the process of α-phenylethanol dehydratation has been studied. It was shown, that activity of catalyst depends on the predominating diameter of pores. The methods of changing the porous structure of γ-Al2O3 with the purpose of increasing its catalytic activity were considered. Thermal or hydrothermal treatment of active aluminium oxide allows to obtain the porous structure, providing the maximum activity of catalyst in the process of α-phenylethanol dehydratation. It was also shown, that conversion of α-phenylethanol and selectivity are determined by the surface concentrations of Broensted and Lewis acid centres. The rate of catalyst deactivation (coke formation) is proportional to the concentration of base centres. The influence of content of sodium cations on the acid-base properties and activity of catalyst was determined. Purification of used γ-Al2O3 from sodium cations results in the catalyst, having the maximum catalytic activity.
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