【摘要】 基于0.08mol/LH2SO4介质中,痕量铊(Ⅲ)催化溴酸钾氧化偶氮胂M(AsAM)的褪色反应,建立了测定痕量铊(Ⅲ)的催化光度法。讨论了酸度、反应物浓度、反应温度、时间、干扰离子等因素的影响。研究了反应的最佳条件,并测定了一些动力学参数,催化反应的表观活化能为70.12kJ/mol。方法检出限为0.17μg/L,线性范围为0～20μg/L。在25mL溶液中,测定0.5μg铊(Ⅲ)的相对标准偏差为3.4%(n=11)。结合溶剂萃取分离技术,用于测定废水及土壤样品中痕量铊(Ⅲ),回收率为97.0%～103.0%。更多还原

【Abstract】 Based on the catalytic effect of trace thallium(Ⅲ) on discoloring reaction of arsenazo M with potassium bromate in 0.08 mol/L sulphuric acid solution,a method for the determination of trace thallium(Ⅲ) by kinetic spectrophotometry was established.The factors such as acidity,concentration of reactants,reactive time,temperature,influence of coexisting ions on the reaction and the optimum conditions of reaction and some kinetic parameters were determined. The apparent activation energy of the reaction is 70.12 kJ/mol .The detection limit is 0.17 μg/L and the linear range of determination is 0-20 μg/L for thallium(Ⅲ).The relative standard deviation for the determination of 0.5 μg thallium(Ⅲ) in 25 mL solution is calculated to be 3.4%(n=11).Combined with solvent extraction separation,the method has been applied to the determination of trace thallium(Ⅲ)in waste water and soil samples with the recovery of 97.0%-103.0%.更多还原