Fe2O3/MgO载氧体反应性能的研究

Study on Reaction Properties of FeO/MgO Oxygen Carrier

采用浸渍法制备不同Fe/Mg质量分数的Fe2O3/MgO载氧体和Fe2O3-CuO/MgO载氧体。在热重分析仪(TG)上进行还原实验和循环实验,研究了反应温度、Fe/Mg质量分数和CuO活性组分对载氧体还原性能和循环性能的影响。通过氢气程序升温还原(H2-TPR)和X射线衍射(XRD)表征技术对载氧体的物化性能进行分析。结果表明:随着Fe2O3质量分数的增加,Fe2O3/MgO载氧体的还原性提高,但单位质量Fe2O3的H2消耗量不断降低;Fe的质量分数在13.5%~72%时,Fe2O3-CuO/MgO载氧体的反应活性相对于Fe2O3/MgO载氧体有所下降;随着温度的升高,Fe2O3/MgO载氧体的失重率增大;随着Fe2O3质量分数的降低,Fe2O3/MgO载氧体的还原性能下降,但载氧体的循环稳定性提高,这可能是由于Mg质量分数的增大,改善了载氧体的循环稳定性。

Fe2O3/MgO and Fe2O3-CuO/MgO oxygen carriers(OCs) with different Fe/Mg mass ratios were prepared by impregnation method to conduct reduction and cycle experiments in a thermogravimetric analyzer, so as to study the effects of the following factors on the reduction and cycle properties of the oxygen carriers, such as the reaction temperature, Fe/Mg mass ratio and CuO active component, etc. Meanwhile, the physicochemical properties of above OCs were analyzed by H2-TPR and XRD characterization techniques. Results show that as the mass fraction of Fe2O3 increases, the reducibility of the Fe2O3/MgO OC increases, but the hydrogen consumption per unit mass of Fe2O3 drops continuously;when the mass fraction of Fe lies in 13.5%-72%, the reactivity of the Fe2O3-CuO/MgO OC would be lower than that of the Fe2O3/MgO OC. The weight loss rate of the Fe2O3/MgO OC increases with the rise of reaction temperature;as the mass ratio of Fe2O3 decreases, the reduction property of the Fe2O3/MgO OC decreases, but its cycle stability increases, which might be resulted from the increase of Mg mass fraction.