- 期刊
- OpenAccess
Fabrication of Iron-based Oxygen Carriers on Various Supports for Chemical Looping Hydrogen Generation
摘要
Fe_2O_3/Al_2O_3 and Fe_2O_3/TiO_2/Al_2O_3 oxygen carriers were fabricated and evaluated for chemical looping hydrogen generation (CLHG) using a TGA system and a fixed-bed reactor. Oxygen carriers were converted to around 33% in a fixed-bed reactor to ensure uniform reduction. The reduced oxygen carrier was tested for steam generation, where in all cases Fe_2O_3/Al_2O_3 displayed a better conversion than Fe_2O_3/TiO_2/Al_2O_3. It was found that increasing the reaction temperature from 800 to 850 °C had little effect for either oxygen carrier, but a further increase to 900°C resulted in an increased steam conversion. A higher steam flow rate caused a lower overall steam conversion but a higher H_2 production. A higher feed rate of reduced oxygen carrier let to a higher steam conversion up to a rate of 18.4 and 14.9 g min^(-1) for Fe_2O_3/Al_2O_3 and Fe_2O_3/TiO_2/Al_2O_3, respectively. A final comparison was performed with up to 50 redox cycles, where Fe_2O_3/Al_2O_3 showed superior reactivity in the first cycles but ended at a conversion of 54.6% with Fe_2O_3/TiO_2/Al_2O_3 ending at a conversion of 64.6%.