Nitric oxide decomposition and selective catalytic reduction by methane over Ba/MgO catalysts

Vannice and coworkers have demonstrated that several of the catalysts which are effective in the oxidative coupling of methane (e.g. Li/MgO, La2O3, Sr/La2O3, etc.) also promote the selective reduction of NO with CH4. They suggested that methyl radicals may be formed on the surface, and these radicals would react with NO as an intermediate step in the reduction mechanism. Xie et al. found that gas phase CH3radicals were indeed present when CH4 reacted with O2 over a Sr/La2O3 catalyst and that CH3radicals reacted with NO to form a CH3NO intermediate. The presence of O2 in the system was needed to generate CH3radicals, presumably because NO was not capable of forming the centers that were necessary for the activation of CH4.

Nitric oxide decomposition and selective catalytic reduction by methane over Ba/MgO catalysts Conference Paper