Chemical Engineering & Technology, Vol.35, No.7, 1281-1290, 2012
Chemical Looping Dry Reforming as Novel, Intensified Process for CO2 Activation
Chemical looping dry reforming (CLDR) is a novel, intensified route for CO2 activation. Two nanostructured carriers (Fe-BHA and Fe@SiO2) are synthesized, characterized, and evaluated with regard to activity and stability in thermogravimetric and fixed-bed CLDR reactor studies over a temperature range of similar to 500-800 degrees C. Fe-barium hexaaluminate (Fe-BHA) shows fast redox kinetics and stable operation over multiple CLDR cycles, while Fe@SiO2 exhibits poor activity for CO generation due to a partial loss of the core-shell structure and formation of silicates. While the latter could be removed via a two-step oxidation scheme, carrier utilization remained well below that of Fe-BHA (similar to?51?% versus similar to?15?%). However, the two-step oxidation configuration turns the net endothermic CLDR process into a net exothermic process, opening up a highly efficient autothermal process alternative.