碱熔-碲共沉淀富集-电感耦合等离子体原子发射光谱法测定石油化工废催化剂不溶渣中铂钯

采用过氧化钠高温熔解样品,3.0～4.5 mol/L盐酸介质中二氯化锡还原、碲共沉淀富集铂、钯,选择Pt 265.945 nm、Pd 340.458 nm作为分析谱线,建立了电感耦合等离子体原子发射光谱法(ICP-AES)测定石油化工废催化剂不溶渣中铂、钯的方法。样品中铂的质量浓度在2～27 μg/mL、钯的质量浓度在0.7～20 μg/mL范围内,校准曲线线性方程分别为I _Pt =3 624 × ρ_Pt－180.4和I _Pd = 9 869 ×ρ_Pd－220.9,线性相关系数R²均为0.999 98。方法中铂、钯的检出限分别为0.017 μg/mL和0.004 2 μg/mL。测定石油化工废催化剂不溶渣样品中109～1 342 g/t铂和37～977 g/t钯,结果的相对标准偏差(RSD,n=5～11)分别为1.1%～1.9%和1.1%～3.6%,测定结果与火试金富集-电感耦合等离子体原子发射光谱法的测定结果一致,铂、钯的回收率分别为99%～100%和100%。

Determination of platinum and palladium in insoluble slag of waste catalyst for petrochemical industry by inductively coupled plasma atomic emission spectrometry after alkali fusion-tellurium coprecipitation enrichment

The sample was fused with sodium peroxide at high temperature. Then, the platinum and palladium were enriched by stannous chloride reduction and tellurium coprecipitation in 3.0-4.5 mol/L hydrochloric acid medium. Pt 265.945 nm and Pd 340.458 nm were selected as the analytical lines. The determination method of platinum and palladium in insoluble slag of waste catalyst for petrochemical industry by inductively coupled plasma atomic emission spectrometry (ICP-AES) was established. When the mass concentration of platinum and palladium in sample was in range of 2-27 μg/mL and 0.7-20 μg/mL, the linear equation of calibration curves was I_Pt=3 624×ρ_Pt-180.4 and I_Pd=9 869×ρ_Pd-220.9, respectively. The linear correlation coefficients (R²) were both 0.999 98. The detection limit of platinum and palladium in this method was 0.017 μg/mL and 0.004 2 μg/mL, respectively. The content of platinum (109-1 342 g/t) and palladium (37-977 g/t) in insoluble slag of waste catalyst for petrochemical industry was determined according to the experimental method. The relative standard deviation (RSD, n=5-11) was 1.1%-1.9% and 1.1%-3.6%, respectively. The determination results were consistent with those obtained by fire assaying enrichment-inductively coupled plasma atomic emission spectrometry. The recoveries of platinum and palladium were 99%-100% and 100%, respectively.