Determination of Rhodium in Waste Rhodium-Loaded Carbon Catalyst Samples Using Teflon Pressure Vessel-Assisted Sample Digestion and ICP-AES

Abstract

A novel method for the determination of rhodium in waste rhodium-loaded carbon catalyst samples was established by inductively coupled plasma atomic emission spectrometry after samples digested by Teflon pressure digestion vessel with aqua regia. Such experiment conditions were investigated as the influence of sample dissolution methods, digestion time, digestion temperature and interfering ions on the determination. The results indicated that the digestion effect was optimum with samples digested 8 hour at 180 °C. Al, Fe, Mg, Ca and Si in samples had no effect on the determination of rhodium. Experiment indicated rhodium concentration within the range of 0 ~ 150 mg L-1 had a linear relation with emission intensity. The recovery was 99.20% ~ 100.73 %, and the relative standard deviation was 1.8 %. A satisfactory result was obtained when applying the proposed method in the practical sample.