Water Splitting by MnOx/Na2CO3 Reversible Redox Reactions

Thermal water splitting by redox reactants could contribute to a hydrogen-based energy economy. The authors previously assessed and classified these thermo-chemical reactions. Mn3O4/MnO/NaMnO2 multi-step cycles were demonstrated have high potential. present research experimentally investigated the MnOx/Na2CO3 system both in an electric furnace concentrated solar at 775 825 °C, respectively, using 10 250 g of reactants. characteristics all determined particle size distribution, porosity, XRD SEM. With milled grain sizes below 1 µm, offer large surface area for heterogeneous gas/solid reaction. Up complete (oxidation/reduction) furnace. After cycles, equilibrium yield appeared be reached. Mn3O4/Na2CO3 cycle showed efficiency 78% °C. was still close 60%. At MnO/Na2CO3 80% conversion during 1, which decreased 77% after 10. Other reactant compounds achieved significantly lower yield. In furnace, highest (>95%) obtained with A final assessment process economics revealed that least 30 40 would needed produce H2 price 4 €/kg H2. To meet competitive prices 2 H2, over 80 should achieved. experimental economic results stress importance improving reverse system.