Search Results (151)

Water represents the fundamental source of life for all human and animal populations; however, its consumption has become increasingly hazardous due to high levels of pollution. Modern agricultural practices rely heavily on pesticides, which significantly contribute to water contamination and imbalances in aquatic ecosystems. Moreover, another critical category of pollutants consists of pathogenic bacteria that proliferate in aquatic environments, mainly originating from hospital and urban wastewater because of human activity. Considering these major environmental and health challenges, the present study aims to develop an optimized method for water treatment by synthesizing magnetic silica-based aerogels using a microfluidic vortex chip and systematically varying synthesis parameters to enhance material performance. The physicochemical properties of the aerogels were characterized using XRD, FTIR, SEM, EDS, and BET. The pesticide adsorption capacity of the materials was evaluated using FT-ICR HR-MS analysis, which demonstrated the high efficiency of the aerogels in removing a complex mixture of pesticides. In parallel, antimicrobial efficacy was assessed against E. faecalis, E. coli, and P. aeruginosa isolated from surface water, hospital wastewater, and the influent of a well-known wastewater treatment plant in Bucharest, as well as against ATCC reference strains. Additionally, the study investigated the biocompatibility and biological responses of magnetic aerogels using MTT assays, nitric oxide production, lactate dehydrogenase release, intracellular ROS levels, and quantification of total protein, malondialdehyde, and reduced glutathione in HaCaT and HEK293 cell lines. The results confirm the efficiency and application potential of the developed materials and emphasize the importance of optimizing synthesis to achieve high-performance aerogels for effective decontamination of polluted waters. Full article

Contamination of water and soil with a wide range of pollutants, including pesticides, pharmaceuticals, and industrial chemicals, remains a significant environmental challenge. Carbon-based materials are widely recognized for their high adsorption capacity, chemical stability, and the possibility to tailor their surface and structural properties. In recent years, ionic liquids (ILs) have been explored as useful media and functionalization agents in the preparation of such materials. Their unique physicochemical properties can facilitate activation, influence pore structure, and introduce specific functional groups that improve interactions with target contaminants. This review summarizes recent developments in the use of ILs for the synthesis, modification, and regeneration of carbonaceous adsorbents. Particular attention is given to IL-assisted activation techniques, surface functionalization strategies, and reported improvements in adsorption performance. Key challenges, such as the environmental impact and cost of ILs, as well as prospects for developing more sustainable IL-based processes, are also discussed. Taken together, these findings highlight the relevance of IL-enabled carbon materials for practical adsorption processes, including water and wastewater treatment, selective pollutant removal, and regeneration-driven purification systems. Full article

This study optimized a homogeneous photo-Fenton process for the simultaneous degradation of the emerging pesticides atrazine and methomyl in water using Response Surface Methodology (RSM). A synthetic agricultural effluent containing 2.0 mg L⁻¹ of each pesticide (COD = 103.2 mg O₂ L⁻¹; TOC = 26.1 mg C L⁻¹; BOD₅ = 45.8 mg O₂ L⁻¹) was treated in a recirculating UV–H₂O₂/Fe²⁺ reactor. A 2³ factorial design with replication and five central points identified the H₂O₂/Fe²⁺ ratio and irradiation time as the main factors controlling mineralization, achieving up to 88.9% COD removal in the best screening run. Steepest-ascent experiments were then performed to approach the region of maximum response, followed by a rotatable Central Composite Design (20 runs). The resulting quadratic model explained 98.14% of the COD variance (R² = 0.9814; adjusted R² = 0.9646; predicted R² = 0.8591; CV = 0.2736%) and predicted a maximum COD removal of 94.5% at a volumetric flow rate of 0.466 L min⁻¹, a Fenton ratio of 12.713 mg mg⁻¹, and a treatment time of 71.0 min. Experimental validation under these optimized conditions yielded highly reproducible removals of 94.2 ± 0.04% COD and 81% TOC, confirming the predictive capability of the RSM model and demonstrating a high degree of organic mineralization. The response surfaces revealed that increasing the Fenton ratio enhances oxidation up to an optimum, beyond which hydroxyl-radical self-scavenging slightly decreases efficiency. Overall, the integration of multivariable experimental design and RSM provided a robust framework to maximize photo-Fenton performance with moderate reagent consumption and operating time, consolidating this process as a viable alternative for the mitigation of pesticide-laden agricultural wastewaters. Full article

In this study, a novel Bi₂O₃/BiOBr_0.9I_0.1 (BO0.9−BBI0.1) composite photocatalyst was successfully synthesized via a single-pot solvothermal method for the efficient degradation of 2,4-dichlorophenoxyacetic acid (2,4-D) under visible light. The structure, morphology, and optical properties of the photocatalyst were characterized through X-ray diffraction (XRD), Scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), UV–vis diffuse reflectance spectra (DRS), Steady-state photoluminescence (PL), and Electrochemical Impedance Spectroscopy (EIS). The composite exhibits a 3D hierarchical morphology with increased specific surface area and optimized pore structure, enhancing pollutant adsorption and providing more active sites. Under visible light irradiation, BO0.9−BBI0.1 achieved a 92.4% removal rate of 2,4-D within 2 h, with a reaction rate constant 5.3 and 4.6 times higher than that of pure BiOBr and BiOI, respectively. Mechanism studies confirm that photogenerated holes (h⁺) and superoxide radicals (·O₂⁻) are the primary active species, and the Z-scheme charge transfer pathway significantly promotes the separation of electron-hole pairs while maintaining strong redox capacity. The catalyst also demonstrated good stability over multiple cycles. This work provides a feasible dual-modification strategy for designing efficient bismuth-based photocatalysts for pesticide wastewater treatment. Full article

Hetero-multicomponent metal oxide catalysts are attracting increasing attention for wastewater remediation due to their tunable band structures, synergistic redox activity, and enhanced stability. This review thoroughly evaluates recent progress in the synthesis and application of such catalysts, highlighting Ti–Cu–Zn nanostructures as a representative case study. We examine synthesis approaches—including hydrothermal, biosynthesis, precipitation, and spray-based methods, with additional insight into sol–gel and other less commonly applied techniques—with emphasis on their suitability for constructing layered and multicomponent heterostructures. Mechanistic aspects of photocatalysis, Fenton and Fenton-like processes, adsorption, and electrochemical routes are discussed, with particular focus on charge separation, reactive oxygen species (ROS) generation, and pollutant-specific degradation pathways. Comparative performance metrics against antibiotics, pesticides, dyes, and fertilizers are analyzed, alongside considerations of leaching, reusability, and scale-up potential. Importantly, while significant progress has been made for organic micropollutants, applications in heavy metal remediation remain scarce, highlighting an urgent research gap. By situating Ti–Cu–Zn systems within the broader class of multicomponent catalysts, this review not only synthesizes current advances but also identifies opportunities to expand their role in sustainable wastewater management, including field deployment, regulatory compliance, and integration into decentralized treatment systems. Full article

The present study targets key limitation ‘separation after the process’ that is responsible for the loss of the photocatalyst in water treatment during heterogeneous photocatalysis. Therefore, eco-friendly nanostructured ZnO coatings were engineered by the doctor blade technique through the immobilization of green ZnO nanomaterials onto alumina substrate. ZnO/BPE 30 and ZnO/BPE 60 coatings were obtained from banana peel extract-based ZnO powder (ZnO/BPE). Likewise, ZnO/GTE 30 and ZnO/GTE 60 were prepared using green tea extract-based ZnO powder (ZnO/GTE). XRD characterization verified hexagonal wurtzite ZnO phase, while HRSEM analysis revealed that the flat surface of ZnO/BPE had rod-like nanostructures below 120 nm, and ZnO/GTE had spherical, porous nanoparticle networks with less than 70 nm. According to UV–vis spectrometry, all four coatings have bandgaps of ~5 eV. The highest efficiency for the solar-driven photocatalytic degradation of emerging organic pollutants was for ciprofloxacin (among pesticides clomazone and tembotrione; pharmaceuticals ciprofloxacin and 17α-ethinylestradiol; and mycotoxin zearalenone) in ultrapure water with the presence of all studied ZnO-based coatings, after 60 min of simulated solar irradiation. Its highest removal (89.1%) was achieved with ZnO/GTE 30, also having good reusability across three consecutive cycles in river water, thus supporting the application of eco-friendly, immobilized ZnO nanomaterials for wastewater treatment and environmental remediation. Full article

Wastewater treatment plants (WWTPs) have been identified as the major sources of contaminants of emerging concern (CECs) in water bodies, as they are not designed to remove organic micropollutants efficiently. Consequently, many technologies have been explored for WWTP upgrading, including activated carbon adsorption. However, the high production cost and environmental challenges associated with activated carbon production limit its application in industrial settings. Therefore, a wide range of alternative materials has been investigated as potential replacements. In this study, biochar produced from waste raspberry biomass was evaluated as an adsorbent for the removal of pharmaceuticals and pesticides quantified in the secondary effluent of municipal WWTP. The results showed that the biochar efficiently removed almost all detected compounds, except for three compounds (clarithromycin, propranolol, and linuron). The wastewater pH (6–8) did not significantly affect removal efficiency significantly, and kinetic tests demonstrated rapid adsorption. The potential for biochar reuse was confirmed through three consecutive batch adsorption cycles. A comparative study between biochar and powdered activated carbon (PAC) revealed some differences in efficiency, primarily attributed to the larger surface area of PAC. π-π interactions, hydrogen bonding, and pore-filling were proposed as possible adsorption mechanisms based on the adsorption efficiency and biochar characterization. Full article

This study investigates the potential of corn cob-derived biochars produced at 400 °C (BC400) and 700 °C (BC700) as heterogeneous catalysts for the degradation of organochlorine pesticides, lindane and β-endosulfan, through persulfate-based advanced oxidation processes (AOPs). BC700 exhibited enhanced degradation performance compared to BC400, likely due to its greater surface area, higher aromaticity, and lower surface polarity. Under optimized conditions (3.0 mM persulfate, pH 7.02, 0.2 g/L biochar), BC700 enabled the removal of up to 94% of β-endosulfan and 82% of lindane within four hours. Quenching experiments suggested different dominant degradation pathways: singlet oxygen (¹O₂) appeared to play a key role in lindane degradation, while β-endosulfan degradation likely involved both radical (SO₄^•−, HO^•) and non-radical mechanisms. Reusability tests indicated that BC700 retained catalytic activity for β-endosulfan across multiple cycles, whereas lindane degradation efficiency decreased, possibly due to surface fouling or catalyst deactivation. Experiments conducted in real surface water highlighted the influence of matrix components, with partial inhibition observed for β-endosulfan and an unexpected improvement in lindane removal. These results point to the promise of high-temperature corn cob biochar as a selective and potentially reusable catalyst for AOPs in water treatment, warranting further investigation into regeneration strategies and matrix-specific effects. Full article

Currently, continuous population growth and unsustainable industrialization have caused ongoing water pollution, with harmful consequences for human health and the environment. Persistent organic pollutants (dyes, active pharmaceutical compounds, pesticides, etc.) are discharged into water from various industrial, agricultural, and domestic activities. Therefore, wastewater treatment through sustainable technologies is imperative, representing a great and real challenge for worldwide research. Photocatalysis, an innovative and green technology, uses advanced oxidation processes in the presence of a photocatalyst, usually a semiconductor with expanded light absorption ability and high conductivity for photogenerated charge carriers. Molybdenum disulfide (MoS₂) is an n-type semiconductor with different morphologies, variable bandgap energies (Eg = 1.1–2.63 eV), and numerous applications. Although pristine MoS₂ exhibits special structural and optoelectronic properties, its photocatalytic activity can be further improved through various strategies, and constructions with the heterojunctions construction with other semiconductors being frequently pursued. This review extensively studies the recent research (the last 4 years) on MoS₂ and MoS₂-based heterojunction (I-type, II-type, Z-scheme, S-scheme) photocatalysts for degrading organic contaminants under simulated and sunlight irradiation in wastewater treatment. Even if in a relatively short time (a few years) valuable studies have been reported on this topic, there are still numerous challenges facing future research. Full article

Wastewater-derived microplastics (WW-MPs) are increasingly recognised as reactive vectors for aromatic organic contaminants (AOCs), yet their role in contaminant fate remains insufficiently constrained. This review synthesises current knowledge on the transformation of microplastics in wastewater treatment plants, including fragmentation, oxidative ageing, additive leaching, and biofilm formation, and links these processes to changes in sorption capacity toward phenols, PAHs and their derivatives, and organochlorine pesticides (OCPs). We summarise the dominant adsorption mechanisms-hydrophobic partitioning, π-π interactions, hydrogen bonding, and electrostatic and, in some cases, halogen bonding-and critically evaluate how wastewater-relevant parameters (pH, ionic strength, dissolved organic matter, temperature, and biofilms) can modulate these interactions. Evidence in the literature consistently shows that ageing and biofouling enhance WW-MP affinity for many AOCs, reinforcing their function as mobile carriers. However, major gaps persist, including limited data on real wastewater-aged MPs, lack of methodological standardisation, and incomplete representation of ageing, competitive sorption, and non-equilibrium diffusion in existing isotherm and kinetic models. We propose key descriptors that should be incorporated into future sorption and fate frameworks and discuss how WW-MP-AOC interactions may influence ecological exposure, bioavailability, and risk assessment. This critical analysis supports more realistic predictions of AOC behaviour in wastewater environments. Full article

This review presents a comprehensive overview of electrochemical-based technologies as emerging and sustainable methods for treating pesticide-contaminated wastewater. Core processes, including electro-Fenton, electrocoagulation, and electrochemical oxidation, as well as their hybrid combinations, have demonstrated high degradation efficiency, operational flexibility, and the ability to achieve complete mineralization of persistent pesticides. A bibliometric analysis covering 1997–2025 reveals growing global interest in these technologies, particularly in hybrid systems such as photoelectro-Fenton and solar-assisted electrochemical treatments, which offer improved degradation rates and reduced energy demand. Compared to conventional and biological approaches, electrochemical methods provide superior pollutant removal without generating excessive sludge or secondary contamination. Future advancements should focus not only on optimizing operational parameters but also on overcoming current methodological limitations through the development of durable and selective electrode materials and the integration of renewable energy sources, ultimately enhancing process efficiency and sustainability. Coupling electrochemical treatments with complementary physicochemical or biological methods may further improve mineralization and reduce costs. Overall, electrochemical technologies represent a promising pathway toward efficient, scalable, and environmentally friendly wastewater treatment systems capable of mitigating pesticide pollution and protecting aquatic ecosystems. 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

Pesticide residues from agrochemicals pose significant environmental and public health risks due to their persistence and widespread contamination of soil, water, and crops. The persistent challenge of pesticide contamination requires innovative and sustainable treatment strategies to safeguard public health and environmental integrity. Although wastewater treatment plants (WWTPs) are designed to mitigate these pollutants, their efficiency varies, and certain pesticides persist or transform into more toxic by-products during treatment. Therefore, developing alternative methods for the effective removal of pesticide residues is imperative. This review critically evaluates the potential of adsorption, particularly using green adsorbents, as a sustainable and efficient approach for removing pesticide contaminants from soil and wastewater. Green adsorbents, derived from agricultural and industrial by-products such as sea materials, biomasses, humic acid, spent mushroom substrate, biochar, and cellulose-based adsorbents, offer a cost-effective, abundant, and environmentally friendly solution for soil treatment and water purification. Their high pollutant-binding capacity, selectivity, and affinity make them promising candidates for widespread application in soil and wastewater treatment. Ongoing research focuses on optimizing the scalability and real-world application of these adsorbents for large-scale remediation efforts. In conclusion, addressing the risks posed by pesticide residues necessitates revisiting agricultural practices and wastewater treatment strategies. The integration of green adsorbents offers a sustainable approach to mitigating pesticide contamination, thereby protecting public health and supporting environmental sustainability. This review highlights the importance of adopting green adsorbents as viable alternatives to conventional treatment methods, emphasizing their potential to revolutionize wastewater management and mitigate the adverse impacts of pesticide residues on ecosystems and human well-being. Full article

Biopurification systems are designed for the treatment of pesticide-containing agricultural wastewater; their biologically active matrix, the biomixture, can be modified to enhance the pesticide removal capacity. Two approaches, fungal bioaugmentation with Trametes versicolor and amendment with biochar, were applied for the potential improvement of biomixtures’ capacity to remediate myclobutanil-contaminated wastewater. The conventional biomixture (B) and its modifications, either bioaugmented with Trametes versicolor (biomixture BT) or supplemented with pineapple biochar (5% v/v) (biomixture BB), were spiked with myclobutanil at a very high concentration (10,000 mg/kg) to simulate extreme on-farm events such as the disposal or leakage of commercial formulations. The dissipation followed a bi-phasic behavior in every case. Both modifications of the conventional biomixture increased the dissipation rates, resulting in estimated DT₅₀ values of 61.9 (BB) and >90 days (BT) compared to biomixture B (DT₅₀ = 474 days). The assessment of biomixtures’ detoxification was carried out with two different bioindicators: a seed germination test in Lactuca sativa and an algal growth inhibition test. Some degree of detoxification was achieved for all biomixtures in both indicators, with the exception of the biochar-containing biomixture, which, despite showing the fastest myclobutanil dissipation, was unable to maintain a steady detoxification trend towards the algae over the course of the treatment, probably due to biochar adverse effects. This approach seems promising for removing persistent myclobutanil from agricultural wastewater and demonstrates the dissipation capacity of biomixtures at extremely high pesticide concentrations likely to take place at an on-farm level. Full article

Coagulation–sedimentation remains a widely used process in drinking and wastewater treatment, yet its performance for emerging contaminants requires further evaluation. This review summarizes recent advances in conventional and novel coagulant systems for the removal of pesticides, pharmaceuticals, per- and polyfluoroalkyl substances (PFAS), natural organic matter (NOM), and micro- and nanoplastics (MNPs). The efficiency of conventional aluminum- and iron-based coagulants typically ranges from 30–90% for NOM and pesticides, 10–60% for pharmaceuticals, <20% for PFAS, and up to 95% for microplastics. Modified and hybrid materials, including titanium-based and bio-derived coagulants, demonstrate superior performance through combined mechanisms of charge neutralization, adsorption, and complexation. The zeta potential of particles was identified as a key factor in optimizing MNP removal. The ability of iron and titanium to form complexes with organic ligands significantly influences the removal of organic pollutants and metal–organic interactions in water matrices. While most research remains at the laboratory scale, promising developments in hybrid and electrocoagulation systems indicate potential for field-scale application. The review highlights that coagulation is best applied as a pretreatment step in integrated systems, enhancing subsequent adsorption, oxidation, or membrane processes. Future studies should focus on large-scale validation, energy efficiency, and the recovery of metal oxides (e.g., TiO₂) from residual sludge to improve sustainability. Full article