Emerging contaminants are increasingly recognized as persistent soil pollutants with often-unknown environmental effects, yet Mediterranean monitoring data remain scarce. This study compared three established sample preparation approaches and subsequently validated and applied the best-performing QuEChERS-based procedure coupled to LC–HRMS for the simultaneous determination of 29 pesticides and 7 pharmaceuticals in soil. The modified EN 15662:2018 QuEChERS approach exhibited the best overall analytical performance. Validation following SANTE 11312/2021 (v2026) guidelines showcased good linearity (R2 > 0.992), acceptable recoveries (86% within 70–120%), precision (RSDs ≤ 18.1%), and sensitivity (LOQs: 0.01–2.5 ng/g). Negligible matrix effects were observed for 78% of compounds, while measurement uncertainty remained below 50%. Preliminary application to pear samples demonstrated potential method applicability to fruit matrices, although further matrix-specific validation is required. Analysis of 16 samples from northeastern Greece revealed 15/36 compounds in 62.5% of samples, with carbamazepine and imidacloprid as the dominant residues and fungicides as the most prevalent class. Importantly, 27% of the detected compounds were no longer approved in the EU. Ecological risk assessment using toxicity exposure ratios (TERs) and risk quotients (RQs) identified imidacloprid, carbamazepine, and terbuthylazine as medium risks. This workflow supports soil monitoring under the EU Soil Monitoring Law and One Health strategy.
Multifunctional hybrid spheres were developed via ionic gelation, using sodium alginate as an encapsulating matrix to integrate TiO2, Fe3O4, activated carbon, hypochlorite-impregnated clinoptilolite zeolite, and metallic copper, followed by chitosan coating and glutaraldehyde cross-linking to enhance mechanical stability. The material combines photocatalytic, adsorbent, antimicrobial, and magnetic functions in a single system, expected to support partial treatment of contaminated water. X-ray diffraction confirmed the expected crystalline phases with no impurities. Physicochemical evaluation showed reductions in turbidity (1.8 to 0.7 NTU), total hardness (306 to 150 mg/L), iron (0.4 to 0.01 mg/L), and lead (<0.001 mg/L), while free residual chlorine remained within permissible limits. Microbiologically, fecal coliforms decreased from 83 to <1.5 CFU/100 mL and total coliforms from 839 to 19 CFU/100 mL. Photocatalytic activity, evaluated using methylene blue, showed an absorbance decrease from 0.38 to 0.17 A.U. over 4 h, corresponding to a blank-corrected removal of 95.5% relative to clean water, fitted to a pseudo-first-order kinetic model (R2 = 0.8868). These results demonstrate a synergistic effect among adsorption, photocatalysis, disinfection, and magnetic recovery, positioning the hybrid spheres as a promising alternative for sustainable water treatment technologies.
This study reports the development, optimization and mechanistic evaluation of bio-based cellulose/lignin–tannin membrane adsorbents for the removal of representative inorganic and organic water pollutants: Cr(VI), Pb2+, difenoconazole (DFC) and bisphenol A (BPA). Waste cellulose fibers (wCF) from cigarette-package paperboard were converted into reactive membrane constituents by amino/ester and epoxy functionalization and subsequently cross-linked with epoxy-modified kraft lignin (EpKL), with or without tannic acid (TA), yielding wCF/EpKL and wCF/EpKL/TA membranes. Response surface methodology was used to optimize formulation parameters, while structural, morphological, and physicochemical analyses supported successful functionalization, cross-linking, and formation of porous, structurally modified surfaces. At 298 K, the Langmuir adsorption capacities of wCF/EpKL/wCF/EpKL/TA reached 85.37/88.78 mg g−1 for Cr(VI), 155.6/163.9 mg g−1 for Pb2+, 51.80/84.49 mg g−1 for DFC, and 194.4/195.4 mg g−1 for BPA, respectively. Isotherm, kinetic, and thermodynamic analyses indicated favorable, heterogeneous, and spontaneous adsorption involving specific surface interactions and diffusion-related contributions. Spectroscopy-supported mechanistic interpretation suggested that metal species are retained mainly through complexation with amino, phenolic, and oxygen-containing groups, together with electrostatic interactions, whereas DFC and BPA adsorption involves hydrogen bonding, hydrophobic interactions, and π–π interactions with lignin/tannin aromatic domains. Fixed-bed experiments confirmed the applicability of the membranes under continuous-flow conditions, while regeneration, stabilization/degradation, and soil-burial tests supported their potential within a more sustainable water treatment cycle. Overall, the results demonstrate that waste-derived cellulose/lignin–tannin membranes are promising regenerable sorbents for the adsorption of chemically diverse inorganic and organic pollutants.
Currently, approximately 80% of the energy used worldwide comes from fossil fuels. The production of bioethanol from agro-industrial waste requires pretreatment due to the latter’s rigid structure and resistance to degradation. In this work orange peel (OP) was pretreated with deep eutectic solvents (DESs), varying the molar ratio of the mixture to delignify the OP, exposing cellulose and hemicellulose, in order to improve the yield in the acid hydrolysis process with H3PO4 to produce reduced sugars. SEM, FTIR, and XRD were used to evaluate the structural changes in OP with and without pretreatment. Optimal pretreatment was achieved using ChCl/U at a 1:4 molar ratio, yielding 31.58 g of reducing sugars per 100 g of pretreated OP after 150 min, compared with 12.09 g of reducing sugars per 100 g of untreated OP after 300 min. The holocellulose content after pretreatment increased by 28%. Significant differences were found in the reducing-sugar yield and the structure of OP with and without pretreatment; DESs are useful for biomass delignification, thus enabling increased reducing-sugar production through acid hydrolysis.
Expanded polystyrene (EPS) is costly to reprocess, occupies substantial landfill space, and presents significant challenges for reuse. The development of innovative methods for EPS recycling is therefore a promising area of research. This study explores the possibility of fabricating a dense foamed matrix from EPS and using it to produce strong acid cation (SAC) exchange resins for water purification. As an alternative to dissolution-based recycling, we propose a physical, environmentally friendly method involving the saturation of the pristine EPS matrix with CO2 and its mixtures (modifying agents) under pressure. This approach enables the formation of a dense porous system while eliminating the need for subsequent solvent removal and cleaning. The modified EPS demonstrates a several-fold increase in density compared to the initial material and an SSA = 50–60 m2/g according to CO2 sorption measurements. The ability to tailor pore size and density simply by varying the modifying agent, pressure, and exposure time was investigated. Structural analysis via SEM as well as N2 and CO2 sorption measurements revealed that the modification process critically dictates the pore architecture: treatment with pure CO2 and a CO2 + H2 mixture resulted in the formation of meso- and macropores while preserving the presence of micropores in the material. FTIR spectroscopy and EDS analysis were employed to study the sulfonation of EPS and its resulting cation-exchange capacity. The kinetics of cations’ sorption was studied using capillary electrophoresis, and the static equilibrium ion exchange capacities were determined for both unmodified sulfonated EPS and modified sulfonated EPS towards Na+ and Ca2+ ions at various salinities of the model solutions. The resulting resins exhibited high sorption capacities, achieving 0.7–1.4 eq L−1 for Na+ and 0.3–1.0 eq L−1 for Ca2+ ions, while the sulfonated sample treated with the CO2 + H2 mixture exhibited the highest equilibrium capacity. The proposed methodology is relevant to both water purification and plastic waste recycling.
