Oxidative conversion of propane in a microreactor in the presence of plasma over MgO based catalysts-an experimental study

In this work, oxidative cracking of propane was studied in a microreactor containing a catalyst. A dielectric barrier discharge (DBD) allows one to generate a cold microplasma, which activates propane forming radicals, at room temperature and atmospheric pressure. Homogeneous and well crystalline thin layers of MgO and Li/MgO catalysts, 25 μm thicknesses, were deposited in the microchannel using sol−gel method and by micropipetting. Li/MgO catalyst showed higher propane conversion and olefins selectivity compared to MgO. The latter one suggests that (i) radicals formed by DBD in gas phase are differently terminated depending on the catalyst surface and (ii) the surface of Li/MgO catalyst present more selective sites than MgO, such as [Li+O-] centers and F-type defects that are generated and able to react at room temperature. Surprisingly large amounts of products with higher molecular weight than propane, that is, C4, C4+ were also observed due to only C−C bond formation