Determination of Palladium and Rhodium in Catalysts on Board Vehicles by Super Micro wave Digestion and Inductively Coupled Plasma Emission Spectrometry
To optimize the accurate and rapid analysis of Pd and Rh content in on-board catalysts,this study combined with the determination of super microwave digestion and ICP-AES,aiming at the problems of difficult digestion,insufficient digestion and low digestion efficiency of on-board catalysts,explored the influence of diges-tion system,digestion temperature and digestion time on sample digestion in the super-microwave digestion instru-ment.On this basis,the interference of co-existing elements in ICP-AES was investigated,and an efficient and fast method was established to dissolve the on-board catalyst and directly determine ICP-AES.The results show that;In the digestion system of HCl+H2O2,the Pd and Rh elements in the sample can be completely dissolved by high-speed stirring digestion at 250 ℃ for 45 min,and the dissolution of co-existing elements can be effectively controlled,thus reducing the interference of ICP-AES determination of the tested elements.The RSD of the method were Pd 1.50%and Rh 1.60%,and the recoveries were Pd 98.93%and Rh 101.85%,respectively.The results were consistent with the confirmed values of standard samples and met the reliability evaluation criteria.Compared with the common methods such as alkali melting,atmospheric acid dissolution,closed digestion,and microwave di-gestion combined with tellurium co-precipitation,this method greatly reduces the digestion time,reduces the process of tellurium co-precipitation separation and enrichment of precious metals,and improves the determination efficiency of on-board catalysts.The establishment of this method can realize more efficient and rapid digestion of on-board catalysts,and accurately determine and evaluate Pd and Rh contents by ICP-AES,which provides a reference for the evaluation of Pd and Rh in on-board catalysts and related samples.
super microwave digesterinductively coupled plasma emission spectroscopypalladiumrhodiumdiscarded on-board catalyst