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为了用原子吸收光谱法测定地质试料中的锡,研究了一种迅速而灵敏的方法。该方法是把生成氢化物和加热石英原子化结合使用,或把溶剂萃取和碳管原子化结合使用。普通硅酸盐岩石和沉积物是用高氯酸、硝酸和氢氟酸的混合物分解,并用稀盐酸和草酸溶解。氢化锡是与1％的四硼酸钠和0.6M盐酸在一种自动氢化物发生器中反应生成的,并将其输送至石英原子化器中。溶剂萃取和碳管原子化器相结合的方法可适用大量干扰元素和(或)耐熔锡矿物的试样。在这种情况下,试样用混合酸分解或用碳酸钠和硼酸熔融。用醋酸丁酯生成锡三辛磷氢化物(TOPO)的络合物的方法,可将锡从含40mg氯化铝,浓度为2.4M的盐酸溶液中萃取出来。有机溶剂中的锡则用碳管原子化器测定。在锡的检测中,利用生成氢化物和石英槽原子化器时其检测极限为0.1ppm;利用碳管原子化器和溶剂萃取时,其检测极限为0.4ppm(即试样的0.5g)。锡含量高于0.5ppm时,其相对标准偏差低于14％。上述方法可满意地应用于大量地质参照试样的分析。
In order to determine tin in geological samples by atomic absorption spectroscopy, a rapid and sensitive method was studied. In this method, the formed hydride is used in combination with heated quartz atomization, or the solvent extraction and carbon nanotube atomization are used in combination. Ordinary silicate rocks and sediments are decomposed with a mixture of perchloric acid, nitric acid and hydrofluoric acid and dissolved with dilute hydrochloric acid and oxalic acid. Tin hydride is formed by the reaction of 1% sodium tetraborate and 0.6 M hydrochloric acid in an automatic hydride generator and delivers it to the quartz atomizer. Solvent extraction and carbon tube atomizer combination of methods applicable to a large number of interfering elements and (or) refractory tin mineral sample. In this case, the sample is decomposed with a mixed acid or with sodium carbonate and boric acid. Tin can be used to generate tin trioctyl phosphine hydride (TOPO) complex method, the tin can be extracted from 40mg aluminum chloride, a concentration of 2.4M hydrochloric acid solution. Tin in organic solvents is measured using a carbon nanotube atomizer. In the detection of tin, the detection limit is 0.1ppm when using hydride generation and quartz cell atomizer, and 0.4ppm (0.5g of sample) when using carbon tube atomizer and solvent extraction. When the tin content is higher than 0.5ppm, the relative standard deviation is less than 14%. The above method can be satisfactorily applied to the analysis of a large number of geo-referenced samples.