水中苯酚的酸性铬蓝K-溴酸钾催化动力学光度测定法

Determination of trace phenol by catalytic-kinetic spectrophotometry with acidic chrome blue K-potassium bromate system

目的建立水中苯酚的酸性铬蓝K-溴酸钾催化动力学光度测定法。方法水样经预处理后加入0.1 g/L酸性铬蓝K、0.1 mol/L溴酸钾溶液、0.2 mol/L硫酸溶液,45℃恒温水浴。以不加水样为空白,于522 nm处测量二者吸光度差值(ΔA),绘制标准曲线,计算检出限。结果当苯酚浓度在0.02~0.8μg/ml时,与ΔA呈良好的线性关系,回归方程为ΔA=0.368 1c+0.030 7,R2=0.995 8,检出限为0.019 4μg/ml。平均回收率为96.6%~101.6%,RSD为0.76%~1.21%。结论该方法操作简单,反应快速,灵敏度和准确度较高,适用于水中苯酚的测定。

Objective To develop a new catalytic spectrophotometric method with acidic chrome blue K-potassium bromate system for the determination of trace phenol. Methods Under the maximum absorption wavelength of 522 nm, the reaction was allowed to run for 25 min in 45 ~C water bath, the content of phenol had a linear relationship with the values of AA in the range of 0.02-0.8 p^g/ml. Results The linear equation was AA=0.368 lc＋0.030 7 （r2=0.995 8）. The detection limit was 0.019 4 p.g/ml, the average recovery rates were 96.6%-101%, and the RSDs were 1.1%-2.8%. Conclusion The method is simple, sensitive, accurate and applicable to the determination of trace phenol in wastewater.