催化裂化废催化剂上镍形态的XRD研究

摘要

The mechanical mixtures of silica or alumina with NiO,impregnated silica or alumina with Ni sources,together with 5 fresh FCC catalysts and 10 commercial FCC equilibrium catalysts(ECAT) were characterized by XRD to investigate the nickel species on FCC catalyst.The results show that for the mixture samples,NiO is detected reliably when Ni content is higher than 519 μg/g or 694 μg/g,respectively.Compared with the impregnated alumina,NiO can be detected at low Ni loading on the impregnated SiO2.As to the alumina impregnated,NiO cannot be found until the Ni contamination content is over 117 900 μg/g.No NiO can be observed until the Ni content is higher 15 000 μg/g and 700-2 500 μg/g for fresh FCC catalysts and ECATs,respectively.%为了确定催化裂化废催化剂上镍的存在形态,采用X射线衍射法对氧化镍与氧化硅或氧化铝机械混合物及浸渍镍源的氧化硅或氧化铝载体、5个催化裂化新鲜剂和10个催化裂化平衡剂进行表征.结果表明:NiO与SiO2或Al2O3机械混合样品中Ni质量分数分别高于519μg/g或694μg/g时即可检测到NiO;与Al2O3载体相比,SiO2载体在较低的镍污染量下即可检测出NiO,但Al2O3载体在污染Ni质量分数高于117 900μg/g时才能检测出NiO;不同类型的催化裂化新鲜剂在污染Ni质量分数高达15000μg/g时仍无法检出NiO;对Ni质量分数在0.07%~2.50%范围内的典型催化裂化平衡剂均未检测到NiO的存在.