铈锆复合氧化物中稀土总量的测定

Determination of the total amount of rare earth in Cerium Zirconium Oxide

适用于铈锆复合氧化物中稀土含量的测定,对样品溶解、试剂用量、分离等条件进行考察。试料用氢氧化钠-过氧化钠的混合熔剂在750℃下分解,经分离、过滤去除了锆、硅、铁等干扰元素,在1.8~2.0的pH值下,形成稀土沉淀,950℃下灼烧稀土沉淀,计算得到铈锆复合氧化物中稀土含量。结果表明,试料溶解后,经过过滤分离,可以彻底分离去除高含量的锆和其他干扰元素,沉淀中残留的共存元素不干扰铈锆复合氧化物中稀土含量的测定。对铈锆复合氧化物中稀土含量进行加标回收试验,回收率为98%~103%。采用此方法测定铈锆复合氧化物中稀土含量,结果的相对标准偏差(RSD,n=10)小于0.50%,测定范围为20%~80%。

Experiments of analysis method of determination of the total amount of rare earth in cerium zirconium oxide and the best determination conditions were investigated,the samples were treated with NaOH-Na2 O2 at 750 C.Rare earth in cerium zirconium oxide was precipitated by oxalic acid in pH 1.8~2.0.The results show that the interference of coexisting elements can be eliminated by acid insoluble separation,ammonia separation and oxalic acid precipitation.The addition recovery was between 98%and 103%.The method was applied to the determination of total rare earth in cerium zirconium oxide.The relative standard deviation(RSD,n=11)was less than O.50%.and the determination range was 20%~80%.