Análises de compostos orgânicos não específicos no esgoto sanitário doméstico através das técnicas RMNq e HPLC-(UV/MS)-SPE-ASS-NMR

Abstract

The growth of industrial deployment and urbanization play a major role in the degradation of global environmental and resource depletion mainly in countries in development such as Brazil. The problems regarding water pollution in Latin America have been well-documented, and there is no evidence of substantive effort to change the situation. There are a large number of organic pollutants that leads several damages to the ecosystem, threatening human health and are flushed to wastewater treatment plants (WWTPs). The WWTPs are responsible for the removal of natural and anthropogenic pollutants from the sewage and, for this, play an important role in protection of human health and the environment. Due to the varying operational conditions, process and quality, the wastewater treatments need to be monitored continuously to ensure a reliable and efficient operation. Therefore, the NMR analyses are widely used in the study of different components of wastewater such as complex organic matter (fulvic and humic acids), sludge and organic contaminants. In the present work, we employed two methods to study wastewater samples: non-targeted 1D (13C and 1H) and 2D NMR spectroscopy analyses to characterize the largest possible number of compounds in urban wastewater; and analysis by HPLC-(UV/MS)-SPE-ASS-NMR to detect and elucidate the non-specific recalcitrant in treated wastewater, sparing the common use of standards. In the non-targeted 1D NMR analysis, we employed also a method to study wastewater samples by chemometric and quantitative analyses to monitor the seasonal variations and identify anomalous discharges in urban wastewater system. The set of data were constituted of several compounds on which the concentration ranges considerably with treatment and seasonality. An anomalous discharge, the influence of storm water on the wastewater composition and recalcitrant compounds (LAS surfactant homologues) in the effluent were further identified. The seasonal variations and abnormality in the composition of organic compounds in sewage indicated that the employed procedure can be useful to identify the pollution source, to follow up the efficiency of WWTPs plants to design preventive actions in order to protect equipment and preserve the environment.