火试金富集-重量法测定冰铜中金

研究了采用火试金法直接测定冰铜中的金的含量，确定了最佳实验条件。在氧化铅加入量达到铜量的35倍、硼砂加入量为15 g、溶剂样品与Na₂CO₃比为1∶0.7的条件下，且熔融温度为1 100 ℃、恒温温度为1 200 ℃、恒温时间为30 min时样品富集分离熔融制备的铅扣效果最好。分析了5个冰铜实际样品，并与原子吸收光谱法进行对比，研究结果表明：方法分析冰铜中的金含量时，分析结果与原子吸收光谱法分析值相吻合，加标回收率为90%~107%。方法的相对标准偏差为2.4%~4.9%。

Determination of gold in matte by fire assaying enrichment-gravimetric method

The direct determination of gold content in matte by fire assaying was studied. The optimal experiment conditions were obtained. When the added amount of lead oxide was 35 times of copper, the added amount of sodium borate was 15 g, the ratio of solvent sample and Na₂CO₃ was 1:0.7, the melting temperature was 1 100 ℃, the constant temperature was 1 200 ℃, and the constant temperature time was 30 min, the sample enrichment, separation and prepared lead button by melting were best. Five actual matte samples were analyzed. The results were compared with those obtained by atomic absorption spectrometry. It was found that, the analysis results of gold content in matte by this method were consistent with those obtained by atomic absorption spectrometry. The recoveries of standard addition were90%-107%. The relative standard deviation (RSD) was 2.4 %-4.9 %.