Binary catalytic systems for the industrial cyclohexane oxidation process

Abstract

This paper proposes the possibility of creating an efficient binary catalytic system for the industrial oxidation process of cyclohexane based on a compound of a metal of variable valence and a salt of perfluorinated sulfonic acid. Two-component binary mixtures of the main component and additive were used for the study. In addition to industrial cobalt naphthenate, other salts of metals of variable valences, such as manganese naphthenate, as well as stearates of copper, nickel, and cerium, were used as the main component of the binary mixture. A number of salts of perfluorinated sulfonic acids were used as an additive to the binary mixture. Chromoxane is shown to be the most efficient additive to cobalt naphthenate. In the presence of this binary system at the 50th minute of the process, the conversion of raw materials increased to 10.4 mol.%, which is 22% more than the oxidation of pure cobalt naphthenate, while the selectivity with respect to the target products remains high (79.5 mol.%). It is shown that of a number of compounds of metals of variable valence, the most effective main components of binary systems are cobalt naphthenate and cobalt-cerium catalyst. Carrying out the oxidation of cyclohexane in the presence of such systems allows increasing the conversion of the initial cyclohexane by 1.13 to 1.5 times and thus increasing the rate of oxidation of the hydrocarbon in comparison with the industrial process. It is also important that the use of such catalysts allows conducting the oxidation of cyclohexane to high conversions without losing the yield of the target products.