催化分光光度法测定碳酸盐岩中锇、钌

Determination of Osmium and Ruthenium in Carbonate Rocks by Catalytic Spectro-photometry

对碱熔-催化光度法测定碳酸盐岩中的Os、Ru进行了研究。结果表明,在过氧化钠熔融物料时,加入酸性熔剂硼砂和二氧化硅,可以增加熔融体的流动性,消耗过量的过氧化钠,避免了熔融物在后续硫酸酸化时产生大量过氧化氢,使蒸馏氧化剂K2Cr2O7被还原而失去氧化性,有利于溶液中Os、Ru的完全氧化蒸馏分离。解决了催化光度法测定碳酸盐岩中Os、Ru测定结果偏低、不准确的问题。测定Os、Ru检出限(3σ)分别达到0.0192、0.0194 ng/g,精密度(RSD,n=12)分别为4.75%~15.2%、4.22%~13.9%,准确度(RE)分别为-3.12%^+3.33%、-8.45%^+4.54%。方法可满足地球化学调查样品分析质量要求。

The determination of osmium and ruthenium in carbonate rocks was investigated by the alkali fusion-catalytic spectrophotometry. The results showed that the addition of acidic rholite like borax and silicon dioxide when carbonate material was being melted by sodium peroxide could increase the mobility of the molten body, facilitate the consumption of an excessive amount of sodium peroxide and avoid large amounts of hydrogen peroxide produced by the melt after acidification with sulfuric acid. With the addition of acidic rholite, K2Cr2O7 was reduced and lost the oxidizing potency, so that osmium and ruthenium in the solution could be fully oxidized, distilled and separated. The detection limit （3σ） was 0.0192 ng/g for Os and 0.0194 ng/g for Ru. The precision RSD （n=12） was 4.75%-15.2% for Os and 4.75%-13.9% for Ru. The accuracy （RE） was -3.12%--＋3.33% for Os and -8.45%-＋4.54% for Ru. The method can be applied to analysis of the samples from the geochemical survey.