壳聚糖衍生物修饰电极测定水中NO_2^-的研究

Determination of Nitrite Ion in Wastewater at Schiff's Base Derivative of Chitosan Modified Glass Carbon Electrode

利用水杨醛对壳聚糖进行改性,合成壳聚糖席夫碱类衍生物(S-CTS),将其滴涂在玻碳电极表面成膜。用循环伏安法研究了该修饰电极对NO2-的电催化作用。实验结果表明,以0.1mol/LpH4.0的B-R缓冲溶液为底液,还原峰电流与NO2-浓度在1.8×10-1～70mg/L范围内呈良好的线性关系,相关系数为0.9915,检出下限达4.6×10-3mg/L。用于水样测定,结果满意。

A polymer product S-CTS was prepared by modifying chitosan with salicyclaldehyde.Glass carbon electrode was modified with S-CTS by drop-coating method,and its electrocatalysis effect on reduction of nitrite by films of S-CTS was investigated.Results showed that S-CTS modified electrode could reduce oxidation overpotential of nitrite in B-R buffer solution of pH 4.0,the peak current of reduction was proportional to the concentration of nitrite and a good linear relation from 2.0×10-6 to 1.0×10-3mol/L with a detection limit of 2.3×10-7mol/L was obtained.The method is satisfactory to determining nitrite in wastewater.