Carbon dioxide utilization by chemical looping process over CeO2 modified Fe2O3
Author
Mier González, LorenaDate
2013-05-14Director/es
Derechos
© Lorena Mier González
Palabras clave
Chemical Looping Process
Dry reforming
CeO2-Fe2O3
Ni-Pt catalyst
CO2 utilization
In-situ XRD
Abstract:
Mixed CeO2-Fe2O3 materials with 0, 20, 50, 70, 90 and 100 wt.% are prepared to be tested as suitable oxygen carrier materials for CO2 transformation into CO by means of a chemical looping process (CLP). The samples were characterized with TEM, EDX, SAED and in-situ XRD analysis. Activity and stability were also tested by cycled redox reactions. The generation of CO through H2-CO2 cycles was investigated at 600°C to evaluate the effect of CeO2 upon Fe2O3. The results show that the addiction of Ce to iron oxide has a beneficial effect upon the activity of the material. Redox cycles can be repeated many times without a significant loss of CO2 conversion. However, when performing the CLP with a mixture of CO2 and CH4 as feedstock, the reduction of iron oxide is considerably decreased. Nickel and platinum metals were added to the 50Ce-Fe sample by incipient wetness impregnation to handle this challenge. During the reduction step, CH4/CO2 is converted over Ni-Pt catalyst into syngas, which then reduces iron oxide, giving CO2 and H2O. During re-oxidation of the oxygen storage material by CO2, CO is produced.