Avaliação da tecnologia de membranas na remoção do contaminante emergente Fluoxetina em amostras de água

Abstract

The scientific community has been observing the contamination of water resources with the socalled emerging pollutants, in which medicines are included. These compounds are found in low concentrations in the environment, which can generate adverse and / or synergistic effects in animals and humans. Conventional water and sewage treatment plants are not designed to remove and, consequently, remedy or mitigate water contamination by this type of contaminant. Therefore, advanced treatment technologies are necessary. The membrane separation processes are promising alternatives for removing these micropollutants, and among them, nanofiltration (NF) and reverse osmosis (OI) stand out for the selective separation of these compounds. The objective of this work is the study and evaluation of advanced water treatment technology in the removal of anxiolytic fluoxetine from water, using reverse osmosis and nanofiltration membranes, aiming to improve its quality, as well as life and health, both of the environment and the human population. Three distinct OI membranes and one NF membrane were used. All tests were performed with total recirculation, submitted to the same filtration time. Permeate flows and removal rates were evaluated as responses and different pressure and concentration gradients as variables. The quantification of the drug, in the retained and permeated, was performed by high performance liquid chromatography coupled to a mass spectrometer (LCMS / MS). Both membranes had the expected permeate flow; the pressure and the concentration gradient did not influence the removal rates in the OI membranes. The results demonstrate the removal between 50 and 60% of fluoxetine by the nanofiltration process, indicating the physical-spatial removal, when the concentration was variable; while reverse osmosis removed between 94 and 99%, depending on the filtration module used. The low pressure membrane obtained, in general terms, a higher rate of removal of FLU, varying between 98% and its totality, showing the efficiency of OI treatment of waters contaminated with the psychiatric drug, according to the operational conditions submitted. The mathematical solution-diffusion model explained the removal of FLU by OI, according to a set of variables, indicating that it is a satisfactory physical barrier. In addition, the comparison of the methods was achieved, being able to evaluate the most viable process, highlighting the possibility of using these processes in conventional water treatment.