Pre-concentration of CECs and AMR bacteria by ultra-nano filtration and abatement by thermocatalytic nano-powders, implementing circular economy solution


Scheme (a) and photo (b) of the pilot plant realized in the frame of NanoTheC-Aba project and devoted to the simultaneous filtration of water, detoxification and abatement of water contaminants (Photo credit: Maria Cristina Paganini)

9 March, 2023

The project goal was to deliver a new energy-efficient integrated prototype system for water purification composed of the first-to-be-realised ultra-stable silicon carbide (SiC) ultrafiltration/nanofiltration (UF/NF) membrane, an innovative nano-enabled thermocatalytic energy efficient Packed-Bed Reactor (TPBR), and a nano-enabled antimicrobial microfiltration (MF) membrane. The TPBR beads were obtained by recycling SiC membranes scraps deriving from the ordinary production process and will be coated with thermocatalytic perovskite-nanopowders allowing the full abatement of CECs and of AMR pathogens at mild temperatures without the need for chemicals and light sources. The MF membrane was coated with antibacterial titania-silica-core shell nanoparticles to inactivate AMR bacteria while removing suspended solids. The UF/NF membrane separates the clean permeate stream, ready to be recycled or reused, from the toxic concentrate, which is purified by the TPBR, thus preventing the discharge of CECs and pathogens in rivers and oceans. The new system is compact, amenable to scale-up, and ease to integrate in mariculture, aquaculture, tannery, hospital, and other industrial wastewater treatment facilities, providing safe and efficient operation. The integration of the three components allows the optimization of each system unit both alone and in combination, boosting the efficiency of the process and ensuring high water quality and safety by enabling a water and SiC recycling multi-circular model.

In the project's first 15 months, NanoTheC-Aba prepared an integrated system made of a prefiltering unit with antibacterial functionality (AM-MF), an ultra/nanofiltration membrane (UF/NF) for the pre-concentration of the CECs contaminated water and a thermocatalytic packed bed reactor for the generation of OH radicals able to abate CECs and residues of AMR bacteria via an Advanced Oxidation Process (AOP). We started with the generation of antibacterial SIC membranes for abating AMR pathogens. The role of silica as active support has been studied. Moreover perovskite compounds modified with iron have been prepared to test their stability and especially their thermoelectric properties.