催化褪色光度法测定粉煤灰中痕量钼(Ⅵ)
来源期刊：冶金分析2010年第7期
论文作者：罗道成 刘俊峰
文章页码：62 - 64
关键词：催化光度法； 乙基紫； 钼(Ⅵ)； 过氧化氢； 粉煤灰
Key words：catalytic spectrophotometry； ethyl violet； molybdenum (Ⅵ)； hydrogen peroxide； fly ash
摘 要：在0.01 mol/L H2SO4介质中,痕量钼(Ⅵ)对过氧化氢氧化乙基紫(EV)的褪色反应具有强烈的催化作用,据此建立了测定痕量钼(Ⅵ)的催化光度新方法。对反应介质、试剂用量、反应温度、反应时间及干扰离子的影响等进行了探讨,并确定了最佳反应条件。研究表明,体系的最大吸收波长为590 nm,钼(Ⅵ)质量浓度在0~500μg/L内符合比尔定律,方法的检出限为0.11μg/L。方法可直接用于粉煤灰中钼(Ⅵ)的测定,结果与分光光度法相符,6次测定值的RSD<3%。
Abstract: A new catalytic spectrophotometric method was established for the determination of trace molybdenum(Ⅵ),based on the catalytic effect of trace molybdenum(Ⅵ) on the oxidative discolouration of ethyl violet(EV) by hydrogen peroxide in the medium of 0.01 mol/L sulfuric acid.The effects of reaction medium,reagent dosage,reaction temperature,reaction time and interference ions on the determination had been discussed,and the optimal reaction conditions had been estabilished.The results showed that the maximum absorption wavelength of the system was 590 nm and the detection limit was 0.11 μg/L.Beer’s law was obeyed in the range of 0-500 μg/L for molybdenum(Ⅵ).The proposed method has been applied to the determination of trace molybdenum(Ⅵ) in fly ash,and the results were in good agreement with those obtained by spectrophotometric method with the relative standard deviation of smaller than 3%(n=6).
