CTAB-蒙脱石修饰碳糊电极伏安法测定废水中的苯酚

Voltammetric Determination of Phenol in Waste Water by CTAB-Montmorillonite-modified Carbon Paste Electrode

用十六烷基三甲基溴化铵（CTAB）和蒙脱石修饰碳糊电极，在pH=6的缓冲溶液中，苯酚在0.686V（vs．Ag／AgCl）出现灵敏的氧化峰，苯酚浓度在10^-3 - 10^-5mol，L以范围内与氧化峰电流呈线性相关。石墨碳基质经表面氧化处理，有效增大了氧化峰电流。以KH2PO4-NaAC（pH=6．0）作电解质底液，扫速100mV／s，用所制备的CTAB-蒙脱石修饰碳糊电极测定苯酚，检测限为1．2×10^-2mol．L^-1，平均回收率101．1％，RSD（n=5）6．22％。所建立的方法用于废水中苯酚的测定，能获得良好结果。

Phenol at carbon paste electrode modified by cetyhrimethyl ammonium bromide （CTAB） and montmorillonite produce a sensitive oxidation peak at 0. 686 V （ vs. Ag/AgCl）, and the oxidation peak current is linear correlated with the phenol content ranged from 10^-3 to 10^ -5mol. L^-1. It is discovered that the treatment of surface oxidation of graphite powder can increase the value of ip. The optimum condition for measurement is that 0.1 mol. L^-1 KH2PO4 - NaAC （ pH = 6.0） acted as the supporting electrolyte, and the scanning speed is 100 mV. s^-1. In present method, the detection limit is 1.2 × 10^-7 mol. L^-1, and the average recovery rate is 101. 1% with RSD （n = 5） 6.22%. Established method is applied to the determination of phenol in waste water and a satisfactory result is obtained.