Quantification of Rhodium in a Series of Inorganic and Organometallic Compounds using Cobalt as Internal Standard

An analytical method for the quantification of rhodium using inductively coupled plasma optical emission spectrometry (ICP-OES) and cobalt as internal standard was developed. Rhodium recovery was determined in different samples, which included a certified reference material (CRM), pure rhodium metal, inorganic RhCl3·3H2O salt as well as different organometallic compounds. Excellent rhodium recoveries of 100, 100, 99.0 and 99.7 % with relative standard deviations (RSD) of 1.0, 1.0, 0.3 and 0.4 % were obtained for the CRM, rhodium metal sample, RhCl3·3H2O and [Rh(cupf)(PPh3)(CO)(CH3)(I)], respectively. The accurate recovery of rhodium was, however, affected by the presence of easily ionized elements (EIE) and unmatched acid matrixes with a decrease in rhodium recovery of up to 16%.Validation parameters such as accuracy, precision, specificity, limit of detection (LOD) and robustness were all investigated to confirm the suitability of this newly developed analytical procedure for rhodium determination.KEY WORDS Rhodium, ICP-OES, cobalt internal standard, quantification