Catalysis And Purification Of Organic Waste Gases In Rare Earth Extraction And Separation Workshop

In this paperγ-Al₂O₃ is used as supporter to prepare load type perovskite catalyst. The structure and the specific area of the catalysts are detected by XRD and BET. The catalytic activities are evaluated by catalytic combustion equipment and Gas Chromotograpgy.1. LaCoO₃/γ-Al₂O₃ catalyst is prepared by repeatedly dipping method and excessive solution soaking method, respectively. The results show that the activity of the LaCoO₃/γ-Al₂O₃ catalyst prepared by excessive solution soaking method is better than that of repeatedly dipping method. Being calcinated at 500℃, the burning light-off temperature for toluene is 300℃and the fully transmuted tempareture is 390℃.2. LaCoO₃ is loaded on three differentγ-Al₂O₃ supporters by excessive solution soaking method. The results show that the activity for catalysing toluene is relatively taller while the specific surface area of supporter is relatively larger. Among them, the activity of the catalyst that being loaded on 2#γ-Al₂03 and calcinated at 500℃is best. The burning light-off temperature for toluene is 300℃and the fully transmuted tempareture is 390℃.3. By excessive solution soaking method, choosing 2#γ-Al₂03 supporters, La0.8Sr0.2Co03/γ-Al₂03 catalyst with Sr partly replacing La is prepared and compared with LaCoO₃/γ-Al₂O₃ catalyst. The results show that among the samples calcinated at 500℃, the activity of La0.8Sr0.2CoO₃/γ-Al₂O₃ catalyst is best. The burning light-off temperature for toluene is 310℃and the fully transmuted tempareture is 380℃. However, when calcinated at 800℃, the activity of the catalyst is repressed being led by the growth of the the grain and the decreasing of the surface area of catalyst. Adding Sr fail to improve the activity of catalyzing toluene.4. Changing the elements at B, La0.8Sr0.2MnO₃/γ-Al₂O₃ catalyst is prepared by repeatedly dipping method. The influence of dipping times on the activity of catalyst is investigated. The results show that the more the dipping times, the higher the capacity of the active component, and the better of the activity of the catalyst. Among them, the activity of the catalyst that being dipped ten times and being calcinated at 500℃is best. The burning light-off temperature for toluene is 260℃and the fully transmuted tempareture is 290℃.By meansof the experiments, the optimal loading catalyst with the good activity is La0.8Sr0.2MnO₃/γ-Al₂O₃ that prepared by dipped ten times and calcinated at 500℃. After detected, the activity of the catalyst for kerosene is better. The burning light-off temperature for kerosene is 260℃and the fully transmuted tempareture is 300℃.