Project Portugal 2030

Summary

Based on our large expertise as researchers, in this proposal we will address the dominant aspects in the present research on AGS for the treatment of PhACs coupled with photocatalysis catalysed by novel NM, advancing the scientific understanding, and obtaining new technical improvements with their application simultaneously to remove PhACs and reduce the presence of PMO. The main objectives of the work are: -To full characterize the AGS biomass, in terms of microbial diversity and structure, to follow the variations and to assess the ecological toxicity along the assay. Assays will be performed aiming to determine the toxicological effect of PhACs into the AGS. The results of these studies will allow to establish the range of PhACs concentration where the AGS can be used. Different microbial adaptation strategies will be assayed, increasing wastewater PhACs removal abilities. -To optimize the operational parameters of the AGS reactors aiming to achieve the maximum removal efficiency for both, single and multicomponent contaminated solutions. Parameters as organic load, SRT, HRT and pH will be varied aiming to optimize the removal of contaminants. -To investigate the contribution of each mechanism, biodegradation, and adsorption, for the removal of PhACs. In fact, it is most likely that both mechanisms interact in the bioreactor, but which plays the predominant role in the elimination of PhACs from the water remains unclear. -To synthesize and characterize different nanoparticles aiming at efficient photocatalytic potential in the presence of visible light for PMO disinfection/degradation recalcitrant PhACs. There are multiple choices for different NM to be applied as efficient photocatalytic and antibacterial agents. Ferrite-based and bismuth-based NM are good candidates due to their narrow bandgaps, allowing visible light absorption, and a good base of studies regarding their efficiency as photocatalysts and anti-bactericidal, physicochemical stability, possible magnetic properties, and biocompatibility. For disinfection of water, the best mechanism is the generation of reactive species, that can interact with cell membranes, damaging it, and leading to the death of PMO. -Screening for the best NM by testing their efficiency on photocatalysis under visible light, first by using E. coli and later the others PMO in a small reactor. -The nanoparticles will be immobilized, to prevent them from being dragged by the flow and contaminating the water, in a porous polymer material membrane, Poly Methyl Methacrylate (PMMA), and the scalability of the developed photocatalysts will be performed, using a higher scale photoreactor. -Test the combination of AGS and photocatalysis catalysed by novel NM disinfection technologies for the removal of PhACs and PMO disinfection aiming to obtain a safe, chemically, and microbiologically, water for irrigation purposes. -To develop accurate flow cytometry (FCM) methods for the identification of bacteria, viruses, and other PMO. FCM is a relatively new but promising approach for routine microbial water quality assessment. Quantitative Polymerase Chain Reaction (qPCR) will also be used to complement the analysis. -Bioassays using Vibrio Fischeri will be conducted to assess the potential toxicity of model wastewaters, before and after treatment, attempting to evaluate their detoxification. Toxicity will be correlated with the main products generated during treatment, which identification is also intended.