Search Results (1,031)

This study explores the effectiveness of ultraviolet (UV) irradiation, ozonation (O₃), granular activated carbon (GAC) adsorption, and their combinations (UV/GAC, O₃/GAC) in removing selected pharmaceuticals and common wastewater micropollutants under controlled laboratory-scale conditions. Eight target compounds—candesartan, irbesartan, valsartan, metoprolol, diclofenac, metformin, sucralose, and caffeine—were identified and quantified in real wastewater samples collected from a municipal wastewater treatment plant. Ozonation proved to be the most effective standalone method, achieving complete removal (100%) of five pharmaceuticals and partial removal of sucralose (~60%) and metformin (~17%). The combined O₃/GAC treatment further enhanced overall removal efficiency. In contrast, UV irradiation alone showed limited effectiveness. Importantly, all substances except metformin were fully removed by at least one of the tested methods. These findings underscore the potential of advanced and hybrid treatment technologies—validated here at the laboratory scale—for improving pharmaceutical removal from wastewater and mitigating their environmental impact. Full article

This study presents a sustainable and efficient strategy for removing contaminants of emerging concern (CECs) from wastewater using non-metal-doped pyrochar catalysts synthesized via a green, one-step pyrolytic process from pinewood sawdust, urea, and boric acid. The resulting N- and B-doped pyrochars were evaluated for their ability to activate peroxydisulfate (PDS) and degrade a mixture of 25 CECs (15 pesticides and 10 pharmaceuticals). B-doped pyrochar exhibited superior bifunctional performance, combining high adsorption capacity with efficient catalytic PDS activation. Structural characterization confirmed the incorporation of boron into the carbon matrix, generating electron-deficient Lewis acid sites and enhancing the affinity toward PDS and CECs. Quenching and adsorption–degradation analyses revealed a synergistic combination of radical and non-radical pathways, supported by π–π interactions, hydrogen bonding, and Lewis acid–base interactions. Reusability tests confirmed long-term stability and high degradation efficiency over four cycles. These findings demonstrate the potential of B-doped pyrochar as a cost-effective, stable, and environmentally friendly catalyst for practical wastewater treatment. Full article

This paper deals with the removal of selected micropollutants from water in the laboratory, namely the removal of pharmaceuticals using the sorption materials Filtrasorb F100 and Filtrasorb F400. A group of well-known and available pharmaceuticals was selected for the experiment, which were the over-the-counter analgesics Ibuprofen, Diclofenac, Naproxen and Paracetamol. The model water was created by mixing drinking water from the water supply system of the city of Brno and standards of these pharmaceuticals prepared in the accredited laboratory of ALS Czech Republic. Water filtration was carried out through two filter columns, each filled with a different type of Filtrasorb sorbent. The filtered water was collected at selected time intervals (1, 2, 4 and 6 min) for analysis. The measurements showed that Filtrasorb F100 and Filtrasorb F400 activated carbons have comparable efficiency for the removal for Ibuprofen, Diclofenac, Naproxen and Paracetamol (around 83%). Both activated carbons have proven to be reliable sorbents for the removal of selected micropollutants from water. Full article

This study reports the development of an optimized tight ultrafiltration (UF) membrane prepared from recycled acrylic fiber (polyacrylonitrile, PAN) waste for the efficient removal of organic pollutants from water. Membranes were fabricated using different concentrations of acrylic fiber waste to examine the influence of polymer content on their morphology and performance. The prepared membranes were characterized using scanning electron microscopy (SEM), porosity measurements, contact angle analysis, and mechanical strength testing to evaluate their structural and physicochemical properties. Among the tested formulations, membrane M4, containing 22.5 wt.% acrylic fiber waste, shows the most balanced performance, high mechanical integrity, and good surface hydrophilicity, with a contact angle of about 52° and porosity of 27%. The optimized M4 membrane demonstrates excellent pure water flux of 65 LMH. M4 achieves a flux recovery ratio (FRR) above 80%. Its performance was further evaluated for the removal of humic acid (HA) and paracetamol as a model of organic contaminants. The results also demonstrate strong chemical stability under acidic and basic conditions, highlighting the potential of recycled acrylic fiber waste as a sustainable polymer source for high-performance tight UF membranes. This approach offers an environmentally friendly and cost-effective solution for water purification and pharmaceutical contaminant removal. Full article

Pharmaceutically active compounds (PhACs), pesticides, and poly- and perfluoroalkyl substances (PFAS) are increasingly detected in surface waters at trace concentrations, raising concerns for both aquatic systems and, consequently, human health. Conventional solutions are insufficient to achieve complete removal at trace compound concentrations, highlighting the need for advanced separation technologies. This study aims to comprehensively analyze rejection and removal mechanisms of selected PhACs, pesticides, and PFAS present in water solutions at reported environmentally relevant concentrations (300 ng L⁻¹), using two nanofiltration (NF) and one reverse osmosis (RO) polyamide membrane. PhACs, pesticides, and PFAS were selected to cover a broad range of physicochemical properties, specifically molecular mass (MM), dissociation constant (pKa), and octanol–water partition coefficient (logK_o/w). Rejection values ranged from 42.1% (acetaminophen) to apparent 100% (for multiple compounds), depending on water pH, solute properties, and membrane characteristics. Size exclusion and electrostatic interactions were identified as the primary removal mechanisms, with hydrophobic interactions having a lower impact, particularly for carbamazepine, bezafibrate, and perfluorooctane sulfonic acid (PFOS). Addition of sodium chloride (3 g L⁻¹) decreased rejection of most negatively charged compounds due to suppression of membrane surface charge, although clarithromycin and ofloxacin exhibited improved rejection. Presented results provide fundamental insight into compound-specific membrane rejection and highlight the importance of membrane–solute interactions under environmentally realistic conditions. The results support further optimization of NF and RO for targeted compound rejection and provide a baseline for data-driven membrane process modeling. Full article

Microchannel reactors are among the most important tools used for high-performance continuous-flow synthesis. However, most microchannel reactors manufactured with conventional micromachining techniques are limited to two-dimensional (2D) planar geometries, which pose significant challenges for the custom production of three-dimensional (3D) architectures that offer superior microchemical performance. Using unique nonlinear optical effects of ultrafast lasers, hollow microchannel structures with 3D configurations can be flexibly created within transparent glass materials through either direct removal or subsequent chemical etching methods. This review provides an overview of typical fabrication techniques for 3D glass microchannel reactors based on ultrafast laser microfabrication, as well as their state-of-the-art advancements, including large-scale and high-precision manufacture of all-glass microchannels and the facile integration of online monitoring modules. Moreover, the applications of these fabricated microchannel reactors for various continuous-flow microchemical reactions are introduced. Ultrafast laser-enabled 3D glass microchannel reactors hold great potential for developing innovative and industrial-scale continuous-flow manufacturing processes in chemical engineering and pharmaceutical production. Full article

This study investigates the adsorption of paracetamol from aqueous solutions using natural clinoptilolite and its modified forms. The raw zeolite (p-CLI) was converted into its protonic (H-CLI) and organo-modified (o-CLI) counterparts through ammonium exchange and calcination, and treatment with hexadecyltrimethylammonium bromide (HDTMA-Br), respectively. The materials were characterized by XRD, FT-IR, and SEM analyses. XRD confirmed that the clinoptilolite crystalline framework was preserved after both modifications, while FT-IR and SEM revealed partial removal of exchangeable cations in H-CLI and the formation of an HDTMA-derived organic layer on the external surface of o-CLI. Adsorption experiments were carried out under batch conditions at initial paracetamol concentrations of 0.5–10 mg/L, and equilibrium paracetamol concentrations were determined using differential pulse voltammetry (DPV). The raw clinoptilolite exhibited negligible adsorption capacity (<0.10 mg/g) due to its hydrophilic surface and microporous framework, which limit interaction with neutral organic molecules. Conversion to the protonic form slightly enhanced the adsorption performance (~0.15 mg/g), while HDTMA modification resulted in a modest additional increase (~0.25 mg/g), attributed to the formation of hydrophobic and organophilic surface sites. Overall, the results indicate that surface functionalization can improve the affinity of clinoptilolite toward weakly polar pharmaceuticals; however, the adsorption capacities remain limited. The novelty of this work lies in combining voltametric quantification with a direct comparison of proton-exchanged and surfactant-modified clinoptilolite to elucidate how specific structural and surface changes influence paracetamol uptake. Full article

A sensitive and cost-effective voltammetric sensor using a carbon-containing electrode (CCE) with a renewable surface modified with multi-walled carbon nanotubes (MWCNTs) was developed for the determination of prednisolone in pharmaceuticals and blood serum. The morphological effects of the functionalization process on the MWCNTs were investigated by transmission electron microscopy (TEM). Analysis of the micrographs indicated that the functionalized nanotubes exhibited a higher density of surface defects and a reduced tendency to form bundles compared to their pristine counterparts. Energy dispersive spectrometry (EDS) confirmed that residual iron particles were removed from the MWCNTs during acid functionalization, demonstrating their intrinsic conductivity. The MWCNTs/CCE was characterized by electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). The electrochemical behavior of prednisolone in Britton–Robinson buffer at the MWCNTs/CCE was investigated by linear sweep cathodic voltammetry, while the quantitative determination was performed by differential pulse voltammetry (DPV). Under optimal conditions, the sensor exhibited a linear concentration range from 0.04 to 0.6 μM with a detection limit of 8 nM. The proposed method was successfully applied in the determination of prednisolone in pharmaceutical formulations and blood serum. Full article

The widespread presence of pharmaceutical active compounds (PhACs) in aquatic environments raises significant environmental and public health concerns, particularly through their accumulation in marine biota and potential transfer to humans via seafood. In aquaculture, fish feed is essential for production but may also act as a pathway for contaminants in the marine environment. This study aimed to develop and validate an analytical method for the extraction and quantification of 14 antibiotics and ethoxyquin antioxidant in fish tissue and feed. Two QuEChERS-based extraction protocols were compared: the AOAC 2007.01 method (Method A) using Z-Sep⁺ as clean-up, and the original QuEChERS method (Method B) employing Enhanced Matrix Removal (EMR)-lipid. Ultra-performance liquid chromatography coupled with Orbitrap mass spectrometry using electrospray ionization in positive and negative mode was applied for identification and quantification. Validation included assessment of recovery, linearity, precision, limits of detection and quantification, uncertainty, matrix effects, and process efficiency. Both methods showed good linearity (R² > 0.9899) and precision (<19.7%). Method B achieved superior recoveries for most analytes in both fish tissue (70–110%) and feed (69–119%), with lower uncertainties (<18.4%) compared to Method A. Overall, the original QuEChERS method demonstrated better analytical performance, supporting its application as a green, robust tool for monitoring emerging contaminants in aquaculture products. Full article

Due to industrialization and globalization, water sources are increasingly contaminated with drugs. Among the various methods available, adsorption remains one of the most widely used techniques for drug removal. This work was to develop polysulfone (PSF) membranes integrated with montmorillonite (MMT) clay. The fabricated membranes were subsequently evaluated for their performance in removing diclofenac (DCF) from aqueous solutions. The membranes were characterized using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), Fourier transform infrared spectroscopy (FTIR), contact angle measurements, as well as chemical and mechanical tests. Adding MMT at 1.5 and 2 wt% improved both hydrophilicity and mechanical strength. The natural hydrophilicity of MMT also accelerates the non-solvent/solvent exchange during phase inversion, resulting in higher porosity. These structural and surface modifications increased water permeability (16.36 L·m⁻²·h⁻¹·bar⁻¹), achieved 79% DCF removal, and enhanced antifouling properties. However, increasing the MMT clay content to 2.5 wt% caused particle aggregation, which reduced membrane performance. Fouling resistance tests with bovine serum albumin (BSA) as a model foulant showed a rejection rate of 89% and a flux recovery ratio (FRR) above 82% using an optimized membrane. These findings demonstrate that PSF/MMT membranes can serve as promising candidates for sustainable pharmaceutical wastewater treatment. Full article

Pharmaceutical residues, including a wide range of therapeutic drugs, have been increasingly reported in drinking water sources worldwide, raising environmental concerns due to their potential impact on aquatic ecosystems. Among the available treatment approaches, adsorption has emerged as one of the most reliable methods for eliminating these pollutants. In the present study, metformin was effectively removed from water using a nanocomposite adsorbent consisting of copper nanoparticles anchored onto magnetic chitosan (Cu@MCS). The removal of metformin by Cu@MCS was governed by several mechanisms: surface complexation with copper species, electrostatic interactions, hydrophobic associations between the drug’s methyl groups and magnetite, and hydrogen bonding between metformin’s amino groups and oxygenated functional groups of chitosan. The structural and surface properties of the nanocomposite were characterized through FTIR, XPS, XRD, SEM, and HRTEM analyses. Key experimental factors, such as initial drug concentration, contact time, pH, and ionic strength, were systematically optimized to maximize adsorption efficiency. Adsorption data closely followed the Langmuir isotherm model, with a maximum capacity (q_m;) of 52.91 mg·g⁻¹ at 298 K. Regeneration tests demonstrated excellent reusability, showing only a 3.7% decline in performance after six adsorption–desorption cycles. The Cu@MCS material also proved effective in removing metformin from diverse real water samples, including river water, wastewater, bottled water, and tap water. A notable advantage of this nanosorbent is its magnetic separability, which enables straightforward recovery from solution, even at low contaminant levels and with large sample volumes. These results underline the potential of magnetic chitosan-based nanocomposites as fast, efficient, and reusable adsorbents for the removal of pharmaceutical contaminants from aquatic systems. Full article

Wastewater treatment plants (WWTPs) can still be considered point sources of contamination into receiving aquatic ecosystems, especially for many emerging contaminants, which require additional treatments for their removal. In this study, the impact of a WWTP on the water quality of a river located in the metropolitan area of Milan, Northern Italy, was investigated. A wide range of emerging contaminants (i.e., perfluorinated compounds, pharmaceuticals, and synthetic fragrances) and traditional contaminants (i.e., heavy metals, nutrients, and microbiological parameters) were analyzed, both in the river water and in the wastewater at the inlet and outlet of the WWTP, with the aim of evaluating removal efficiency and the risk for the riverine ecosystem. The results showed that wastewater treatment acts differently on the analyzed compounds, effectively removing nutrients, bacteria, few pharmaceuticals, and most heavy metals, but leaving others unchanged such as perfluorinated compounds and synthetic fragrances, that are thus discharged into the receiving river, especially during rain events due to the activation of sewer overflows. The calculation of the Risk Quotient for organic compounds confirmed the negative impact of the WWTP effluent on the chemical quality of the river water, with a consequent potential ecological risk for riverine biota. This study also verified that certain traditional contaminants (i.e., total nitrogen (TN), total phosphorous (TP), thermotolerant coliforms, Escherichia coli), and contamination tracer (i.e., chloride (Cl), boron (B), and MBAS (Methylene Blue Active Substances) could be effectively measured in real time rather than through classical laboratory analysis and could support timely risk assessment. Full article

Hydroxypropyl cellulose (HPC) is a versatile cellulose ether with two standardized forms: highly substituted (H-HPC), which is water-soluble and thermoresponsive, and low-substituted (L-HPC), which is insoluble but swellable. This systematic review with bibliometric analysis aimed to map the global HPC research landscape (2005–2024), focusing on publication trends, research impact, and thematic directions. Original research articles and conference proceedings indexed in Scopus were included, while reviews and non-research items were excluded. The database was searched on 7 July 2025 using predefined strategies and analyzed using Excel for descriptive statistics and VOSviewer for network visualization. Risk of bias assessment was not applicable; data accuracy was ensured through duplicate removal and the use of standardized bibliometric indicators. A total of 1273 H-HPC and 92 L-HPC publications were analyzed. H-HPC research dominates multidisciplinary applications in drug delivery, 3D printing, thermochromic, and energy materials, whereas L-HPC remains focused on pharmaceutical disintegration and binding. Nevertheless, the field is constrained by reliance on commercial grades and a narrow application focus, leaving broader material innovations underexplored. HPC is positioned as a strategic polysaccharide derivative with expanding translational potential. Future studies should emphasize greener synthesis, advanced functionalization, and industrial scale-up. Funding: Supported by BRIN. Systematic review registration: INPLASY202590019. Full article

Pharmaceuticals such as ibuprofen, paracetamol, and caffeine are commonly found in wastewater due to incomplete removal in conventional treatment systems. This study evaluated three vertical constructed wetland (V-CW) configurations: V1 (gravel–sand with vegetation), V2 (biochar–zeolite with vegetation), and V3 (biochar–zeolite without vegetation). All systems achieved high removal efficiencies for organic matter (Chemical Oxygen Demand (COD): 89.4–91.7%, Biochemical Oxygen Demand over 5 days (BOD₅): 93.3–93.8%, Total Suspended Solids (TSS): 94.5–96.6%) and pharmaceuticals (ibuprofen: 81.8–91.5%, paracetamol: 90.0–94.3%, caffeine: 93.1–97.2%). Statistical analysis showed that substrate type significantly influenced ibuprofen (p = 0.0035) and caffeine (p = 0.0436) removal, while vegetation had no significant effect (p > 0.266). The enhanced performance of biochar and zeolite can be attributed to their high adsorption capacity and microbial support, with adsorption and biodegradation identified as dominant removal mechanisms, as reported in previous research. These findings highlight the importance of engineered substrates in optimizing constructed wetlands for wastewater treatment to improve the removal of emerging contaminants. Future research should focus on long-term substrate performance, cost-effectiveness, and field-scale validation, particularly in regions with vulnerable groundwater systems such as the Yucatán Peninsula. Full article

β-blockers are among the most widely prescribed cardiovascular drugs and are increasingly recognised as emerging pollutants due to their persistence, continuous release into aquatic environments, and potential toxicological effects on aquatic organisms. Their removal in conventional wastewater treatment plants is often inefficient, highlighting the need for biological remediation strategies. This study aimed to identify bacterial strains with the highest potential for the biotransformation of β-blockers. Therefore, we isolated and characterised bacterial strains capable of transforming two commonly used β-blockers—propranolol and metoprolol. The strains BB2 and BB3, which were able to transform propranolol and metoprolol, respectively, were identified as Raoultella terrigena and Stenotrophomonas terrae, respectively. BB2 showed broad metabolic versatility, utilising a wide range of carbon sources, whereas BB3 exhibited limited substrate utilisation. Antibiotic resistance profiling further distinguished the strains, with BB2 resistant across multiple antibiotic classes and BB3 largely sensitive. Co-metabolic assays demonstrated that supplementation with specific carbon and nitrogen sources markedly enhanced β-blocker removal, increasing propranolol biotransformation from 5% to 50% and metoprolol from 4% to 36%. These findings demonstrate the bioremediation potential of newly isolated strains and emphasise the importance of aligning microbial metabolic traits with nutrient conditions to improve pharmaceutical removal in wastewater treatment systems. Full article