Determination of Copper, Iron, Calcium and Magnesium in Gold-Loaded Carbon by Inductively Coupled Plasma-Atomic Emission Spectrometry

This article introduces a method of Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES) for the determination of copper, iron, calcium and magnesium in gold-loaded carbon. After incineration, the residua of the sample were dissolved by HCl and HNO₃, and then the solution in diluted aqua regia was determined by ICP-AES. Factors such as sample drying temperature, the material of the crucible, incineration temperature, incineration time, and media for testing and the interference of the coexisting elements was studied in detail on how they influence the result. The results show that the proper sample drying temperature for the gold-loaded carbon was 150℃. The inoxidability of the quartz pot is higher than that of ceramic crucible, and it also has a lower blank, and stable results. Through an interference test, the coexisting elements in the gold-loaded carbon did not interfere with the determination of copper, iron, calcium and magnesium. This method was applied to the analysis of samples with the relative standard deviations (RSDs) for Cu, Fe, Ca and Mg in the range of 0.84%-1.45%, 0.80%-1.44%, 0.78%-2.69% and 0.96%-2.61%, respectively. Standard addition recoveries for Cu, Fe, Ca and Mg were in the range of 98.5%-100.9%, 99.4%-102.0%, 97.1%-102.5% and 100.7%-104.5%, repectively. The method was simple, and suitable for simultaneous determination of multiple elements.