Engineered biomass-derived activated carbons for microcystins removal in drinking water treatment

Abstract

Drinking water treatment improvement is mandatory to face current water quality challenges, such as the need to control micropollutants present in natural waters sources, such as pharmaceutical compounds (PhCs), and cyanotoxins (naturally produced by cyanobacteria in drinking water source reservoirs under specific conditions) as well as natural organic matter (major precursor of undesirable disinfection by products). . In the frame of EMPOWER+ project, PACs were prepared by physical (steam or CO2) activation of carbonized pine nut shells (PNS, a by-product of food industry, Grupo Cecílio, PT) with particles <150 μm. ll PAC fractions were characterized regarding their textural properties, density, moisture content and pHPZC. The morphology and particle size distribution of the PAC samples of distinct fractions was analysed by Scanning Electronic Spectroscopy (SEM) and Laser Diffraction Spectrometry (LDS). The potential of selected PNS-derived PACs and of a commercial PAC for microcystin-LR (MC-LR) and natural organic matter (NOM) removal is being explored in distinct processes: PAC<20 μm for PAC/Microfiltration (MF) and PAC_20_75 μm for PAC/Coagulation/Flocculation/Sedimentation (CFS). The similar performance of the lab-made materials S2 and C3 when compared to the commercial carbon NORIT SAUF highlights the potential of these biomass-derived materials for drinking water treatment technologies.