Abstract |
The partial oxidation of methane (POM) was studied over eutectic potassium chloride molten salts of the type KCl-MClx (M=Li, Mg, Co, Cu, Zn). The catalytic performance is clearly different and depends on the metal M. The reaction products were CO, CO2, C2 (C2H4, Us). C3 (C3H6, C3H8) and C4 (C4H10). The formation of hydrogen was never detected. The best results for the formation of hydrocarbons were those obtained over the potassium-copper molten salt (KCl-CuCl2, Set >= 80\%) whereas, on the contrary, over KCl-ZnCl2 the formation of CO2 is always dominant. The addition of CeCl3 to KCl-CuCl2 leads to higher conversion of methane and higher selectivity to hydrocarbons. To explain such results, the molten salts liquid phase specificities, namely ion mobility, melting point and redox properties were taken into account. To the best of our knowledge, it is the First time that high selectivities to hydrocarbons are reported over molten salt catalysts. (C) 2012 Elsevier By. All rights reserved. |