电感耦合等离子体原子发射光谱(ICP-OES)法测定含碘附银硅胶中的高含量银OA

Silver-loaded silica gel with iodine is a solid waste formed from the reaction of silver-loaded silica gel and radioactive iodine.The accurate determination of silver content is of great significance for studying its adsorption performance and radioactive iodine purification.Silver in silver-loaded silica gel with iodine mainly exists in the form of silver iodide,which is of high content and poorly soluble,making the accurate determination of silver quite challenging.This study aims to establish a reliable analytical method for the determination of high silver content in silver-loaded silica gel with iodine.Samples were digested using a nitric acid-hydrofluoric acid system,where nitric acid oxidizes iodide ions to iodine,which volatilizes upon heating to promote the decomposition of silver iodide,while hydrofluoric acid removes the silica gel matrix.After digestion,silver was extracted in a hydrochloric acid-thiourea medium and determined by inductively coupled plasma atomic emission spectrometry(ICP-OES).The effects of nitric acid and hydrofluoric acid dosage,hydrochloric acid concentration,and thiourea volume on the determination results were investigated.The results show that the dosage of nitric acid and hydrofluoric acid had little effect on digestion efficiency,while hydrochloric acid concentration and thiourea volume were the key factors affecting silver content.An appropriate amount of thiourea can effectively enhance silver solubility under acidic conditions.Precision and accuracy experiments were conducted on samples,with relative standard deviations(RSD)below 5%and spiked recoveries ranging from 95.8%to 104.0%.The results show that the method has good repeatability and accuracy.In conclusion,this method is suitable for the determination of high silver content in silver-loaded silica gel with iodine and provides an effective technical means for the analysis of silver in such complex matrices.