Reusable passive sampler with carbon nanotubes for monitoring contaminants in wastewater: Application, regeneration and reuse

A POCIS-based approach for the monitoring of pharmaceuticals in wastewater treatment plants: Calibration and deployment challenges

The impact of pharmaceuticals in aquatic environments requires complementary monitoring techniques to the more conventional grab sampling approach for an improved sample representativity. This study explores the application of Polar Organic Chemical Integrative Samplers (POCIS) in the analysis of a wide range of pharmaceutical residues in wastewater effluent, highlighting its advantages over grab sampling. Passive sampling techniques, extending sampling duration several days or weeks, provide continuous and representative data, improving the punctual nature of grab sampling. Despite their advantages, achieving quantitative results remains a challenge. Calibration through precise determination of sampling rates (RS) is recommended to convert the accumulated contaminant mass on the adsorbent to water concentrations. In the present work, 78 pharmaceuticals were preselected for stability suitability for POCIS passive sampling. RS were experimentally determined for 49 stable compounds: 33 of them had not been previously reported and most the other 16 agree with previous published literature. These RS were used to determine the concentration of pharmaceuticals in a wastewater treatment plant (WWTP) near to Barcelona, Spain over 3 weeks. High concentrations of 1,7-dimethylxanthine (2897 ng L-1), 4-acetamidoantipyrine (191 ng L-1), acetaminophen (165 ng L-1) and rasagiline (152 ng L-1) were found. This study examines POCIS deployment strategies, calibration, and analysis methods for 49 pharmaceutical compounds in an WWTP effluent. This research establishes a robust methodology for quantitative passive sampling of pharmaceuticals in aquatic environments, providing critical insights for more accurate monitoring of pharmaceuticals of environmental concern.

Assessment of the application of selected metal-organic frameworks as advanced sorbents in passive extraction used in the monitoring of contaminants of emerging concern in surface waters

Water pollution has become a critical global concern requiring effective monitoring techniques and robust protection strategies. Contaminants of emerging concern (CECs) are increasingly detected in various water sources, with their harmful effects on humans and ecosystems continually evolving. Based on literature reports highlighting the promising sorption properties of metal-organic frameworks (MOFs), the aim of this study was to evaluate the suitability of NH2-MIL-125 (Ti) and UiO-66 (Ce) as sorbents in passive sampling devices (MOFs-PSDs) for the collection and extraction of a wide group of CECs. Solvothermal methods were used to synthesize MOFs, and the characterization of the obtained materials was performed using field-emission scanning electron microscopy (FE-SEM), powder X-ray diffractometry (pXRD) and Fourier-transform infrared (FTIR) spectroscopy. The research demonstrated the sorption capabilities of the tested MOFs, the ease and rapidity of their chemical regeneration and the possibility of reuse as sorbents. Using chemometric analysis, the structural properties of CECs determining the sorption efficiency on the surface of NH2-MIL-125 (Ti) were identified. The MOFs-PSDs were lab-calibrated to examine the kinetics of analytes sorption and determine the sampling rates (Rs). MOFs-PSDs and CNTs-PSDs (PSDs containing carbon nanotubes as a sorbent) were then placed in the Elbląg River and the Vistula Lagoon to sampling and extraction of the target compounds from the water. CNTs-PSDs were selected, based on our previous research, for the comparison of the effectiveness of the MOFs-PSDs in environmental monitoring. MOFs-PSDs were successfully used in monitoring of CECs in water. The time-weighted average concentrations (CTWA) of 2-hydroxycarbamazepine, carbamazepine-10,11-epoxide, p-nitrophenol, 3,5-dichlorophenol and caffeine were determined in the Elbląg River and CTWA of metoprolol, diclofenac, 2-hydroxycarbamazepine, carbamazepine-10,11-epoxide, p-nitrophenol, 3,5-dichlorophenol and caffeine were determine in the Vistula Lagoon using MOFs-PSDs and a high-performance liquid chromatography coupled with triple quadrupole mass spectrometer.

Carbon nanotube-wastewater treatment nexus: Where are we heading to?

Water treatment is crucial in solving the rising people's appetite for water and global water shortages. Carbon nanotubes (CNTs) have considerable promise for water treatment because of their adjustable and distinctive arbitrary, physical, as well as chemical characteristics. This illustrates the benefits and risks of integrating CNT into the traditional water treatment resource. Due to their outstanding adsorbent ability and chemical and mechanical properties, CNTs have gained global consideration in environmental applications. The desalination and extraction capability of CNT were improved due to chemical or physical modifications in pure CNTs by various functional groups. The CNT-based composites have many benefits, such as antifouling performance, high selectivity, and increased water permeability. Nevertheless, their full-scale implementations are still constrained by their high costs. Functionalized CNTs and their promising nanocomposites to eliminate contaminants are advised for marketing and extensive water/wastewater treatment.