溶剂萃取反萃取原子吸收光谱法测定地质物料中的微量金、铟、碲和镓

Determination of Gold, Indium, Tellurium and Gallium in the Same Sample Digest of Geological Materials by Atomic Absorption Spectroscopy and Solvent Extraction——Antiextraction

用氢氟酸和王水分解样品,在抗坏血酸存在下,在盐酸(35％)和氢溴酸(0.15％)介质中,用甲基异丁基酮(MIBK)萃取样液中的金、铟、碲和镓,然后在环已烷存在下,用硫脲(3.5％)溶液进行反萃取,原子吸收光谱法在水相中连续测定上述四种元素。本法各元素测定的相对标准偏差为4.4—6.3％,回收率为92—109％,适用于岩石、土壤等地质物料中ppm级以上的金、铟、碲和10ppm级以上的镓的同时测定。

A sample is lecomposed with hydrofluoric acid and aqua regia. Gold, indium, telluium and gallium can be extracted from the same sample solution by MIBK at the system of hydrochloric acid (35％), hydrobromic acid(15％) in the presence of ascorbic acid to eliminate iron interference. These elements are antiextracted from MIBK with thiourea solution (3.5％)in the presence of cyclohexane, then they are determined by atomic absorption spectrometry in water phase. The relative standard deviation of these elements is 4.4-6.3％, and the recovery is 92-109％. The method can be used as a determination of gold, ineium thllurium (above the grade of ppm)and gallium (above the grade of 10ppm)in the sample of rocks and soils.