Determination of Nitrophenols in Drinking and River Water by Differential Pulse Voltammetry at Boron-Doped Diamond Film Electrode

A differential pulse voltammetric method was developed for the determination of 2-nitrophenol, 4-nitrophenol and 2,4-dinitrophenol at a boron-doped diamond film electrode using electrochemical reduction and of 4-nitrophenol and 2,4-dinitrophenol using electrochemical oxidation. The method was successfully applied for the direct determination of these compounds in drinking and river water in the concentration range from 4 x 10(-7) to 2 x 10(-5) mol L(-1). To improve the limit of quantification, a preconcentration by solid phase extraction from 100 mL and 1000 mL of water samples was used with limit of determination around 2 x 10(-8) and 2 x 10(-7) mol L(-1), respectively.