降低氯化银沉淀对铋吸附的研究

Study on reducing adsorption of bismuth by AgCl

足银样品用硝酸溶解后,直接加入盐酸沉淀分离银基体,用电感耦合等离子体发射光谱法(ICP-OES)测定铋含量,计算加标回收率和相对标准偏差(RSD),发现氯化银沉淀对于铋吸附能力较强,回收率低,达不到检测要求。用盐酸沉淀加入EDTA络合剂和硫氰化钾沉淀去除银基体,都能降低氯化银沉淀对铋的吸附,加标回收率达到85%~99%。

The sample was dissolved by nitric acid.Then the silver matrix was separated by hydrochloric acid.The contents of bismuth in sterling silver were determined by inductively coupled plasma atomic emission spectrometry(ICP-OES),calculating recovery rates and relative standard deviation.It was found that the adsorption capacity of silver chloride has strong adsorption capacity for bismuth,unable to meet the requirements of accurate detection.Using hydrochloric acid to add EDTA and potassium thiocyanate to remove silver matrix,can reduce the adsorption of bismuth by AgCl.Recovery is in the range of 85%~99%.