1.中汽研汽车检验中心(天津)有限公司，天津 300300； 2.中国汽车技术研究中心有限公司，天津 300300
Determination of platinum, palladium and rhodium in automotive metal catalysts by ICP-MS with microwave digestion
Yao Hui1, Wang Yang2, Yang Huiling1
1. CATARC Automotive Test Center(Tianjin) Co., Ltd., Tianjin 300300, China; 2. China Automotive Technology and Research Center Co., Ltd., Tianjin 300300, China
摘要：建立微波消解前处理-电感耦合等离子体质谱法检测车用金属载体催化剂中铂、钯、铑的方法。通过单因素试验和正交试验优化酸配比、称样量、消解温度、消解时间等参数，确定了最佳消解方法：0.1 g样品中加入1 mL盐酸、3 mL硝酸，在消解温度280 ℃下保持45 min，经赶酸碲沉淀富集后溶解上机分析。铂、钯、铑在20～1000 μg/L范围内具有良好的线性关系，相关系数均为1.0000，检出限为铂0.0245 μg/L，钯0.0207 μg/L，铑0.0469 μg/L，7次重复测定结果的相对标准偏差为1.7%～2.2%，加标回收率为93%～100%，测定结果与标准碱熔融方法测定结果无明显差异。该方法满足日常检验要求，且较标准碱熔融法更为方便快捷、绿色环保。
Abstract：A method for the determination of platinum, palladium and rhodium in automotive metal catalyst by using microwave digestion-inductively coupled plasma mass spectrometry was established. Through single factor test and orthogonal test, the acid ratio, sample weight, digestion temperature and digestion time were optimized. The optimal digestion method was determined as follows: 1 mL hydrochloric acid and 3 mL nitric acid were added into 0.1 g sample, and kept at 280 ℃for 45 min. After driving acid, the solution was concentrated by tellurium precipitation and then dissolved. The mass concentration of platinum, palladium and rhodium had good linear relationship in the range of 20-1000 μg/L, the correlation coefficients were all 1.0000. The detection limits of platinum, palladium and rhodium were 0.0245, 0.0207, 0.0469
μg/L, respectively. The relative standard deviations were 1.7%-2.2%(n=7). The recoveries were 93%-100%, there was no significant difference compared with the test results of standard alkali fusion method. The method meet the requirements of daily inspection. Moreover, the method is more convenient, fast and green than the standard alkali melting method.
Keywords：inductively coupled plasma mass spectrometry; microwave digestion; automotive metal catalyst; platinum; palladium; rhodium
Yao Hui，Wang Yang，Yang Huiling. Determination of platinum，palladium and rhodium in automotive metal catalysts by ICP-MS with microwave digestion[J]. Chemical Analysis and Meterage，2021，30(6)：11.