Process for preparing catalytic composition consisting of vanadium oxide, bismuth oxide and a carrier consisting of magnesium oxide, catalytic composition for oxidative dehydrogenation of alkylaromatics and dehydrogenation process of alkylaromatics

摘要

In the present invention, there is disclosed a process for preparing a catalytic composition consisting of a vanadium oxide, a bismuth oxide and a carrier consisting of magnesium oxide, wherein the preparation process is characterized in that it essentially comprises the following steps: preparation of solutions based on derivatives of the components of the catalytic composition; mixing of the solutions prepared and optional aging; drying of the solution obtained; first heating, in the presence of air, of the solid obtained from the drying at a temperature ranging from room value to a temperature of between 290 and 310 degC, for a period ranging from 1 to 3 hours; optional second heating, in the presence of air, of the solid for a time ranging from 0.5 to 2 hours at a constant temperature, ranging from 290 to 310 degC, reached in the first heating; additional heating, in the presence of air, of the solid for a time ranging from 2 to 4 hours at the calcination temperature ranging from 600 to 850 degC; calcination, in the presence of air, of the solid at a constant temperature, ranging from 600 to 850 degC, reached in the additional heating, for a time ranging from 8 to 16 hours. The present invention also discloses catalytic composition prepared in the above-described manner as well as a dehydrogenation process of alkylaromatics by making use of the above-indicated composition.