Electrochemical Technologies for Detecting and Degrading Benzoquinone Using Diamond Films

Abstract

In this work, the detection and quantification of p-benzoquinone (BQ) was performed by differential pulse voltammetry (DPV) with a diamond film sensor. The calibration curve and the limits of detection and quantification for BQ were estimated. DPV was compared to high-performance liquid chromatography (HPLC) analysis, leading to a satisfactory result in terms of stability and sensitive response. As a novel aim, a combined electrochemical method for environmental application has been developed to oxidize and detect BQ using diamond films. A set of galvanostatic electrochemical oxidation experiments with 130 mL of BQ solution were accomplished in order to understand the effect of current density, the concentration of the pollutant and the initial pH using different electrolytes with similar conductivity. The optimal operating conditions were achieved at 33.3 mA cm−2, 100 mg L−1 of BQ at pH 5.0 with 50 mM Na2SO4. Additionally, the evolution of short-chain carboxylic acids of that test was followed over time in order to suggest a possible degradation route. The results were described and discussed in the light of the existing literature.