化学法测定催化裂化催化剂中金属含量

Determination of metal content in catalytic cracking catalyst by chemical method

催化裂化催化剂中金属含量是评价催化剂性能的重要指标之一。为准确测定其金属含量,实验应用压力溶弹在高温高压下将样品熔融,经过滤、洗涤,得到滤液,使用乙二胺四乙酸配位滴定法测定其中氧化铝含量,电感耦合等离子体原子发射光谱仪(ICP-OES)测定氧化稀土(镧或铈)、铁和钠含量。通过与X射线荧光光谱仪(XRF)测定结果进行比较以及多次重复实验,得到测定结果的相对标准偏差(RSD)分别为氧化铝0.01%、氧化钠0.04%、氧化稀土0.1%、铁0.02%。加标回收率为97.8%~105.0%。结果证明,该实验方法可行,且不依附于X射线荧光光谱仪,分析成本低,具有一定的推广价值。

The metal content in the catalytic cracking catalyst is one of the important indexes for evaluating the performance of the catalyst.In order to accurately determine the metal content,the sample was melted under high temperature and high pressure by using a pressure-soluble bomb.After filtering and washing,a filtrate was obtained.Then EDTA was used for coordination titration to determine the content of alumina.The content of rare earth oxides(lanthanum or cerium),iron and sodium was determined by inductively coupled plasma atomic emission spectrometry(ICP-OES).Through repeated experiments and comparison with results of X-ray fluorescence spectrometer(XRF),the relative standard deviation(RSD)of the measured results were 0.01%for alumina,0.04%for sodium oxide,0.1%for rare earth oxide,and 0.02%for iron.The recoveries of the spiked samples were 97.8%~105.0%.The above results prove that the experimental method is feasible and independent to precious X-ray fluorescence spectrometer.The analysis cost is low and has certain promotion value.