Ru-Fe/Al_2O_3氧化-还原性能探究

以Al_2O_3为载体,RuCl_3·xH_2O和FeCl_3·6H_2O为活性组分前驱体,采用吸附-沉淀法制备了Ru-Fe/Al_2O_3和Ru/Al_2O_3催化剂,以马来酸二甲酯加氢合成丁二酸二甲酯为探针反应,结合H_2-TPR和XRD表征技术,考察Fe改性Ru基催化剂的氧化-还原性能及催化活性。经氧化-还原循环处理后,催化剂Ru-Fe/Al_2O_3上马来酸二甲酯加氢活性高于Ru/Al_2O_3。XRD结果显示,经处理的Ru-Fe/Al_2O_3上未见金属Ru的特征衍射峰,而Ru/Al_2O_3上出现了金属Ru的特征衍射峰。结合H_2-TPR结果推断,Ru与Fe之间发生了相互作用,这种协同作用可以改善Ru/Al_2O_3催化剂的热稳定性。

Oxidation-reduction characteristics of Ru-Fe/Al2O3 catalyst

Ru-Fe/Al₂O₃ and Ru/Al₂O₃ samples were prepared via adsorption-precipitation(AP) method with Al₂O₃ as support,RuCl₃·xH₂O and FeCl₃·6H₂O as precursor.Combined with characterization of H₂-TPR and XRD,effects of Fe addition on catalytic performance and oxidation-reduction stability were investigated in hydrogenation of dimethyl meleate(DMM) to dimethyl succinate(DMS).After oxidation-reduction treatment,DMM hydrogenation activity on Ru-Fe/Al₂O₃ was superior to Ru/Al₂O₃.XRD results showed that characteristic diffraction peaks of Ru were not found in Ru-Fe/Al₂O₃ subjected to oxidation-reduction treatment,and characteristic diffraction peaks of Ru were observed in Ru/Al₂O₃.It was inferred from H₂-TPR results that addition of Fe could improve thermal stability of the catalyst Ru/Al₂O₃ due to synergistic effect between Ru and Fe.