Determinação de hidrocarbonetos policíclicos aromáticos e seus derivados utilizando cromatografia líquida acoplada à espectrometria de massas

Abstract

In this study analytical methods using liquid chromatography coupled to mass spectrometry with atmospheric pressure chemical ionization (LC-APCI-MS) were developed for the determination of polycyclic aromatic hydrocarbons in asphalt fractions. Fourteen polycyclic aromatic hydrocarbons (PAHs) 7 nitrogenated derivatives (NHPAs) and 5 oxygenated derivatives (OHPAs) were determined. These compounds are characterized by having two or more condensed aromatic rings, they have mutagenic and carcinogenic activity, and are widely distributed as constituents of complex mixtures in many environments. APCI interface parameters were optimized in order to obtain the highest sensitivity for all compounds. The detection limits of the methods ranged from 0,5 to 346,5 μg L-1 -1 for PAHs, from 0.1 to 57.3 μgL-1 for NHPAs and 0.1 to 6.6 μgL-1 for OHPAs. The limits of quantification were in the range from 1.7 to 1550 μg L-1 for PAHs, from 4.6 to 191 μg L-1 for NHPAs and finally 0.3 to 8.9 μg L-1 for OHPAs. The analytical methods developed were applied to brazilian asphalt samples after their fractionation according to ASTM D4124 and Green method. The concentration of PAHs in this sample ranged from 0.86 to 647 mg kg-1, and NHPAs were 9.26 to 2146 mg kg-1, the OPAHs were not detected.