【摘要】 采用溶胶-凝胶法制备纳米γ-Al2O3载体,浸渍法负载催化剂组分氧化镍(NiO),氧化铈(CeO2)或氧化镁(MgO).750℃的反应温度下在微型固定床反应器中测试催化剂的CO2/CH4重整反应性能.XRD,TG,SEM和TEM表征催化剂失活前后的结构和积碳形貌.结果表明,助剂CeO2有利于提高NiO催化剂的反应稳定性,而助剂MgO却使催化剂的稳定性下降.催化剂上活性组分的存在形态为NiO,催化剂完全失活后NiO消失,而以NiC存在.助剂CeO2延缓了NiO转为NiC的速度,明显提高了催化剂的抗积碳性能和反应稳定性.积碳失活后的催化剂可以通过烧碳再生.更多还原

【Abstract】 The support was made of γ-Al2O3nanoparticles prepared by a sol-gel method,and NiO,CeO2 or MgO were loaded on the support by an impregnation method.The activity and stability of catalysts for CO2-CH4 reforming reaction were tested in a fixed bed microreactor at 750 ℃.The microstructure of the catalysts was characterized by XRD,and the morphology observation of the carbon deposited on the catalysts was characterized by TG,SEM and TEM.The results show that the stability of the catalyst NiO/Al2O3loaded with promoter CeO2 was improved,and loaded with promoter MgO weakened.NiO is the activity species of the catalysts.The catalytic activity of the catalysts disappeared after NiO changing into NiC.This process can be hindered by CeO2loaded on the support,which can obviously improve the catalytic stability of the catalysts and decrease the deposit of carbon on the catalyst.The deactivated catalysts can be recovered when the carbon deposited on the catalysts was oxidized.更多还原