Desenvolvimento de metodologia eletroanalítica para determinação simultânea de benzeno, tolueno e xileno (BTX) em matrizes aquosas usando eletrodo de diamante dopado com boro.

Abstract

In gasoline, among other components, the benzene, toluene and xylene compounds (whose BTX initials will be used throughout this work instead of full names) are present. Such substances are harmful to human health and may even lead to the appearance of tumors. Therefore, the monitoring of BTX in aqueous matrices through the development of an electroanalytical methodology constitutes a work with a broad meaning. In this context, the techniques of cyclic voltammetry and square wave were used for the detection and quantification of BTX in water. The working electrode was boron doped diamond (8,000 ppm). The BTX were shown to be electroactive on the DDB in different potentials in H2SO4 medium (0.1 M), where it was possible to perform the individual analysis of benzene, toluene and xylene, as well as to perform simultaneous determinations in a ternary mixture. The recovery tests in ternary mixtures presented values equal to 98.9% for benzene, 99.2% for toluene and 99.8% for xylene. The limits of detection and quantification for analysis in the ternary mixture were: 23L-1 and 78L-1 for benzene, 73L-1 and 249L-1 for toluene, 96L-1 and 318L-1 for xylene. The results show that the developed electroanalytical methodology allowed to detect and quantify BTX individually and in a mixture with excellent limits of detection and quantification.