【摘要】 <正> 火焰原子吸收法测定岩石中痕量银或金时的富集方法,大都采用有机溶剂萃取后喷雾,该法不易操作,稳定性差,文献用泡沫塑料作载体反相萃取富集银和金已有报导;但银于pH6萃取,不适于富集岩石中银。本文研究了三正辛胺(TNOA)用泡沫塑料作载体,于盐酸-溴化物介质中反相萃取富集微量银和金,用小体积硫脲溶液解吸后,火焰原子吸收法测定银和金,该法与有机溶剂更多还原

【Abstract】 For concentration of micro silver and gold by reverse-phase extraction, a piece of polyurethane loaded with tri-n-octylamine(TNOA), diluted with TBP, is soaked in the test solution. After being vibrated for two minutes before it reaches equilibrium, put the polyurethane into a test tube containing 5 or 10 ml of 2% thiourea and heat in a water oath for5 minutes to get full deadsorption. Then Ag and Au in the solution can be determined by flame atomic absorption spectrometry. For Ag, the concentration of chloric acid and that of sodium bromide in the extraction medium should be controlled in the range of 0. 5 to 2% and 0. 04 to 0. 2M respectively. But it is not necessary for Au. This method is superior to that of nebulization with organic solvent in simplicity, rapidity, stability and generating no harmful gases. Satisfactory analytical results have been obtained with detection limit of O. Oxg/T.更多还原