The Performance Research On Reaction Of Fe-based Oxygen Carrier And CO In Chemical-looping Combustion Process

In recent years, global warming has caused a series of problems, which makes people paying more attention to the problems of greenhouse gas emissions. CO2capture and storage CLC technology is an innovative idea to solve problems of energy and environment, which have become a hot spot in the study of all countries. Meanwhile, the selection of the oxygen carrier is considered as one of themost essential components of the CLC process.In this paper, a series of research of Fe-based oxygen carrier (such as Fe2O3/Al2O3, Fe2O3/SBA-15) were carried out by using fluidized bed reactor, thermo gravimetric analyzer, etc. The dynamics research of Fe2O3(50)/γ-Al2O3was carried out by using program warming thermo gravimetric analysis method. Dynamic parameters of the reaction were obtained by using the Coats-Redfern mechanism to deal with the thermogravimetry experimental dates. The results of experiments show that, Using SBA-15as inert carrier, which can increase specific surface area of the Fe-based oxygen carrier effectively (BET=465.06m2/g), and hold high thermal stability under the high temperature. In the process of CLC, the active component Fe2O3was reduced to FeO in the fuel reactor, and then oxidized thoroughly in the air reactor, thich can improve oxygen transfer capacity effectively, and the reaction process was likely to happen. For further research, Material Studio5.0(MS) calculation software was used in this paper, the reaction mechanism between Fe2O3and CO was studied by using density functional theory (DFT) and so on. Based on adsorptions under different temperatures and reducing processes from Fe3+into Fe2+, Fe+and then into Fe, it was found that Fe2+â†'Fe+was the reaction-controlling step, where efficient partial reduction of Fe2O3into FeO rather than complete reduction into iron may be more energy-saving for CO oxidation, the calculation results are in agreement with experimental study perfectly. These investigations promote the optimizing and applying of oxygen carrier in the chemical-looping combustion with the guidance of the scientific meaning.