Hydrodenitrogenation of pyridine on nickel oxide-tungsten trioxide-aluminum oxide catalyst.

Abstract

The kinetics of hydrodenitrogenation of pyridine over a catalyst containing 6% Ni and 19% W supported on alumina has been investigated in an integral fixed bed tubular reactor at 410 psig. The effect of various variables such as molar ratio, reaction temperature, initial partial pressure of reactants, and residence time on the conversion of pyridine have been studied. The reaction was carried out in a temperature range 120--380°C. The reaction is believed to take place according to the following path: pyridine kov → 3H2 piperidine +pip → +H2 n-pentyl piperidine-pip → +H2 pentane + ammonia. A rate equation for the first reaction namely, hydrogenation of pyridine has been suggested. Hydrogenation of pyridine to piperidine was found to be first order with respect to both pyridine and hydrogen. The apparent rate constant was found to be dependent on the initial partial pressure of pyridine. The rate equation was formulated to be as follows: -ddt pPy= ki+ksR &d1;/H2 P° pPy HPy The activation energy of the reaction and the frequency factor were calculated to be 13.691 K cal/gm mole, and 5.987 x 10-2 gm-molegm-cat-hr N/2m respectively.