Methane activation by NO2 on Co loaded SBA-15 catalysts : The effect of mesopores (length, diameter) on the catalytic activity

Abstract

In a general model of "three-function deNOx" catalyst, the partial oxidation of methane by NO2 is an important step (CH4 + NO2 → CxHyOz + NO). To study the effect of the length and diameter, in the mesopores of SBA-15, we have synthesized catalysts with 3 wt.% cobalt supported on SBA-15, with differences in length and diameter of channels. Three different cobalt species were detected on all catalysts. We demonstrated by TPSR experiments that the activity of cobalt/SBA-15 catalysts is affected by the length, the diameter and connections between mesopores of the SBA-15 supports. We show that by changing textural properties of silica support the temperature of 100% conversion of NO2 into NO can decrease by more than 100 °C.