阻抑乙基橙褪色动力学光度法测定痕量苯酚

摘要

在稀盐酸介质中,苯酚的存在对溴酸钾氧化乙基橙褪色反应有很强的抑制作用。本文利用光度法监测反应过程中乙基橙浓度的变化,并建立了苯酚-溴酸钾-乙基橙体系阻抑动力学光度法测定苯酚含量的方法。在选定条件下,方法的线性范围是0．008μg·mL-1~0．28μg·mL-1,检出限为0．00019μg·mL-1．%In a dilute hydrochloric acid medium,trace phenol showed strong inhibitory effect on the fading reaction of ethyl orange oxidized by potassium bromate. In this paper,the change of ethyl orange concentration in inhibitory reaction was monitored by spec-trophotometry,and based on this a new method for the determination of trace phenol by inhibitory kinetics spectrophotometry in phe-nol-KBrO3-ethyl orange system was established. The detection limit was 0. 00019 μg·mL-1 and the linear range was 0. 008~0. 28μg·mL-1 .