Abstract:The accurate determination of silver in carbon powder is of great significance for its metal balance and trade settlement. The sample was decomposed with nitric acid-sulfuric acid for decarbonizing. The determination method of silver in carbon powder by flame atomic absorption spectrometry (FAAS) was established with air-acetylene flame. The determination medium was 20% hydrochloric acid. The determination wavelengths was 328.1 nm. Under the optimal esperimental conditions, the mass concentration of silver in range of 0.30~3.00 μg/mL showed good linear relationship with the corresponding absorbance. The correlation coefficient was 0.9999. The limit of detection of this method for silver was 0.004 μg/mL. The limit of quantification was 0.013 μg/mL. According to the current situation of domestic, a certain amount of coexisting elements were added into certified reference materials of gold-loaded carbon for the interference tests. The interference tests showed that the coexisting elements had no interference with the determination of silver. The proposed method was applied to the determination of silver in carbon powder samples. The relative standard deviation (RSD, n=7) were between 0.91% and 3.4%. And the results of each sample are consistent with those of the national standard method of GB/T 29509.2-2013 methods for chemical analysis of gold-bearing carbon-part 2: determination of silver content by flame atomic absorption spectrometry. The contents of silver in four certified reference materials of gold-loaded carbon were determined according to the proposed method, and the found results were consistent with the certified values. The accuracy and precision of meet the actual production requirements. The proposed method can be used for the determination of silver in carbon powder.