Abstract:

The determination of gold in ore samples was sealed dissolved by aqua regia and extracted by thiourea solution after foam enrichment,and then was measured by FAAS.The main influencing factors were discussed,such as the acidity of foam enrichment,temperature of enrichment,time of enrichment and the concentration of thiourea solution,time of disengagement etc.The best conditions was obtained through the experiment.The foam enrichment was compared with activated carbon enrichment,and sealed dissolution was compared with opened dissolution.The sealed dissolution-foam enrichment is convenient,fast,low-cost,easy to operate and the result is accurate,the interference element is fewer.The detection limit of this method is 0.02 mg/L,RSD is in the range of 0.80%～ 4.71% and the recovery of standard addition is 98.6%～101.8%.The method was applied to the determination of national standard reference materials and the results are in agreement with the certified values.

Key words: Foam enrichment, Sealed dissolution, Flame Atomic Absorption Spectrometry （FAAS）, Gold