苯酚-溴酸钾-罗丹明6G体系催化光度法测定废水中痕量苯酚

Catalytic spectrophotometric determination of trace phenol in waste water with phenol-potassium bromate-rhodamine 6G system

在0．20mol／L硫酸介质中，苯酚催化溴酸钾氧化罗丹明6G发生褪色反应，生成一种紫红色染料，其最大吸收波长λmax=542nm，据此建立了测定痕量苯酚的催化光度分析方法，并优化了最佳反应备件。在542nm处测定的吸光度增加值AA与苯酚质量浓度在0．02～0．80mg／L范围内呈线性关系，常见的阳、阴离子，间苯二酚和对苯二酚不干扰测定，方法用于废水中痕量苯酚的测定，RSD为2．4％～3．5％，加标回收率为95％～105％。

A rapid and convenient catalytic spectrophotometric method for the determination of trace phenol was established, on the basis of the catalytic effect of phenol on the discoloring reaction of rhodamine 6G and potassium bromate in 0.20 mol/L sulfuric acid medium. A new purple red dye, of which maxmium absorption peak lied at 542 nm was formed in the catalytic reaction and the increase in absorbance, AA was linear with the concentration range of 0.02 - 0.80 mg/L for phenol at 542 nm. The apparent activation energy of catalytic reaction was 112 kJ/mol. Common cations and anions, p-phenol and m-phenol do not interfere with the determination. The method has been applied to the determination of phenol in waste water with satisfactory results.