| 摘要: |
| 1994–1996年间，利用原子吸收光谱仪，对沉积物中有机锡和总锡的石墨炉原子吸收分析方法进行了优化，探讨了分析过程中的仪器条件和改进剂类型。优化后方法的检出限为2.45 μg/L（TPT－锡），特征浓度（相当于产生1%净吸收或0.0044吸光度的待测元素浓度）为4.82 μg/L（TPT－锡）。在这一条件下，采用盐酸酸化－正己烷萃取－氢氧化钠回洗－硝酸氧化的预处理方法，可以使沉积物样品中三苯基氯化锡（Triphenyltin, TPT）的检出限达到41 ng/g（TPT－锡），回收率为106%。应用这一方法对野外模拟实验和黄岛电厂出水口的沉积物样品进行了分析，结果表明，这一方法能够满足对沉积物样品中锡进行分析的要求。 |
| 关键词: 原子吸收光谱法 三苯基氯化锡(TPT) 沉积物 |
| DOI：10.11693/hyhz200003013013 |
| 分类号: |
| 基金项目:国家自然科学基金资助项目，99290600号 |
附件 |
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| ANALYSIS OF ORGANOTIN AND TOTAL TIN IN SEDIMENT WITH ATOMIC ABSORPTION SPECTROMETRY |
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YU Ren-cheng, SONG Xiu-xian, LI Jun, WANG Qi, LIN Qiang, ZHOU Ming-jiang
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Institute of Oceanology, The Chinese Academy of Sciences, Qingdao266071
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| Abstract: |
| A method with Atomic Absorption Spectrometry (AAS) for analysis of organotin and total tin, which were deeply studied in the past two decades, was introduced according to the experiment from 1994 to 1996. Some instrumental conditions, like the ashing and atomizing temperature, modifier, and nitric acid concentration in matrix, were optimized to meet the requirements of analysis.
The experiment showed that, with NH4H2PO4 as a matrix modifier, the absorbance of tin decreased when ashing temperature increased from 350 centigrade to 1000 centigrade, while using K2Cr2O7 as the matrix modifier, the absorbance kept relatively constant. The experiment of atomizing temperature showed that with K2Cr2O7 as the matrix modifier, the absorbance of tin reached the highest value when atomizing temperature was between 1800–2000 centigrade, while for NH4H2PO4, the highest value of absorbance occurred between 2100–2200 centigrade. Since the relatively high absorbance with NH4H2PO4 as the matrix modifier, it was selected for analysis of organotin K2Cr2O7 was selected in total tin analysis because it could reduce the high matrix effect. The difference of nitric acid concentration in matrix from 0.2% to 10% had little effect on absorbance value of tin.
The optimized method had 2σ detection limit of 2.45 μg/L (TPT-tin), and the sensitivity (tin concentration comparable to 0.0044 absorbance) was 4.82 μg/L (TPT-tin). The detection limit for field samples could reach 41 ng/g (TPT-tin) with certain sample pretreatment procedure. The Experiments revealed a relatively high recovery rate of 106%. The method has been applied to analyze triphenyltin (TPT) and total tin in samples collected from a simulation experiment and an effluent discharging site of Huangdao electric power. The results showed that TPT could release from paint to the sediment, and diffused outwards. The higher concentration of total tin compared to TPT revealed the degradation of TPT in sediment. The TPT at the concentration range of detection limit–4000 ng/g could cause variance of benthic community structure and biomass. The analytical result of the sample collected from the site near Huangdao electric power indicates organotin pollution there. |
| Key words: Atomic Absorption Spectrometry (AAS), Triphenyltin (TPT), Sediment |
