Preparation And Property Research Of The Copper-based Three-Way Catalyst Doped With Manganese

With the global state of the growing importance of environmental protection,vehicle emissions standards are more stringent .therefore,Development of high performance three- way catalyst is important.With precious metals Pt,Pd andRh as active components, toγ-Al₂O₃ as the carrier of the three- way catalytic conversion device that can simultaneously purify exhaust gas in the CO,hydrocarbon(HC)and nitrogen oxide(NO_x) and other harmful gases,purification of automobile exhaust is widely used. Such a large number of precious metal catalysts used in Pt, Pd and Rh, and expensive, limiting its use, while the load active ingredientγ-Al₂O₃ thermal stability are also affected. Therefore, the search for both precious metal alternative to, but also improve the thermal stability ofγ-Al₂O₃, also can purify exhaust gas in the CO, HC and NO_x catalyst system into a new research focus. Rare earth materials in the automotive exhaust catalyst demonstrated excellent performance. These catalysts are the most widely studied is the CeO₂ - ZrO₂ solid solution catalysts.This thesis was prepared with good three-way catalytic performance of the new non-noble metal catalyst.The Ce-Zr-Mn-O support was prepared by the co-precipitation method adding cerium and zirconium and manganese nitrate solution and NH₄HCO₃ ammonia solution simultaneously. The CuO/ Ce-Zr-Mn-O catalyst was obtained by impregnation of Ce-Zr-Mn-O with active component Cu aqueous solution. The catalytic activity of the catalyst in CO,C3H6 and NO was investigated. The relationship between the catalytic activity and the structure of catalyst was always explored by means of X-ray diffraction, scanning electron microscopy. The catalyst CuO_0.07/ Ce-Zr-Mn-O exhibited the high catalytic activity。The light-off temperature for CO,C3H6 and NO were 88℃,170℃and 223℃respectively.The CO,NO could be completely converted above 350℃.Prepared by burningγ-Al₂O₃ carriers by coprecipitation Ce-Zr-Mn-O, equal volume impregnation impregnation active component CuO, prepared catalyst CuO/Ce-Zr-Mn/γ-Al₂O₃ ; by catalytic activity of test analysis and scanning electron microscopy (SEM), X-ray diffraction (XRD) and other methods of catalyst activity and structures.The investigation of the CuO/Ce-Zr-Mn/γ-Al₂O₃ indicated that, CuO/Ce-Zr-Mn/γ-Al₂O₃ good three-way catalytic performance. CeO₂-ZrO₂ onγ-Al₂O₃ carrier and active component CuO has a stabilizing effect, avoid CuAl₂O₄ spinel formation。...