催化裂化废催化剂上镍形态的XRD研究

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Al_2O_3机械混合样品中Ni质量分数分别高于519g/μg或694g/μg时即可检测到NiO;与Al_2O_3载体相比,SiO_2载体在较低的镍污染量下即可检测出NiO,但Al_2O_3载体在污染Ni质量分数高于117 900g/μg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15 000g/μg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。

STUDY ON NICKEL SPECIES ON FCC CATALYST BY XRD

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 samples of NiO mechanically mixed with silica or alumina, NiO was reliably detected 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 contamination content on the impregnated SiO2. As to the alumina impregnated, NiO cannot be detected until the Ni contamination content is over 117 900 μg/g. No NiO can be observed until the Ni content is higher 15000μg/g and 700-2 500 μg/g for fresh FCC catalysts and ECATs, respectively.