焙烧温度对NiCoPrLa类水滑石衍生复合氧化物催化性能的影响

Calcination temperature influence on catalytic properties of NiCoLaPr hydrotalcite derived composite oxides

用水热法合成了NiCoPrLa类水滑石,并用XRD和TG-DSC对NiCoPrLa类水滑石的晶相结构和热稳定性进行了表征,合成的类水滑石具有较完整的晶型结构,在439℃后水滑石层状结构开始破坏,形成衍生复合氧化物。运用XRD、TPD、FT-IR、TPR、TPO、SEM等对类水滑石在不同焙烧温度下的衍生复合氧化物的晶体结构、表面性能和抗积碳性能等进行了表征,结果表明:焙烧温度影响衍生复合氧化物的晶相结构和表面性能,焙烧温度高有利于形成结晶完整钙钛矿型衍生复合氧化物,其中焙烧温度为650℃时形成的类水滑石的衍生复合氧化物具有较好的吸附性能,在乙醇水蒸气重整中表现出了较高的活性、H2选择性和抗积碳性。

When NiCoPrLa hydrotalcite synthesized by hydrothermal method,the crystal structure and thermal stability of NiCoPrLa hydrotalcite were characterized by XRD and TG-DSC.Hydrotalcite-like compounds were synthesized by hydrothermal method with unabridged hydrotalcite crystal structure.The hydrotalcite starts to break down at 439 ℃,to form the derived composite oxides.At the same time,the crystal structure,surface properties,catalytic properties and resistance to carbon deposition and sintering properties of derived composite oxides from hydrotalcite calcined at different temperatures were characterized by XRD,TPD,FT-IR,TPR, TPO,SEM.The results show that the calcination temperature influences on the crystal structure and surface properties of the derived composite oxides and can be conducive to the formation of perovskite derived composite oxides at higher calcination temperature.The derived composite oxides of hydrotalcite-like compounds at 650℃calcination temperature show better adsorption performance,with higher activity,H2 selectivity and resistance to carbon deposition in the steam reforming of ethanol.