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16 pages, 3556 KB  
Article
Degradation Pathways and Energy Efficiency on Non-Thermal Plasma for Sulfonamide Antibiotics Removal: A Comparative Study
by Hee-Jun Kim, Donggwan Lee, Sanghoon Han, Jae-Cheol Lee and Hyun-Woo Kim
Processes 2026, 14(8), 1312; https://doi.org/10.3390/pr14081312 (registering DOI) - 20 Apr 2026
Abstract
The non-thermal plasma (NTP) process is a promising advanced oxidation process (AOP) for removing non-biodegradable organics from wastewater, owing to the efficient formation of reactive chemicals. Despite its effective oxidizing capability, the decomposition mechanism of organic pollutants is not well understood. This study [...] Read more.
The non-thermal plasma (NTP) process is a promising advanced oxidation process (AOP) for removing non-biodegradable organics from wastewater, owing to the efficient formation of reactive chemicals. Despite its effective oxidizing capability, the decomposition mechanism of organic pollutants is not well understood. This study evaluates NTP for two representative sulfonamides (SMZ and STZ) and reports on (i) time-resolved removal to the method detection limit, (ii) transformation mapping using LC-ESI/MS/MS, which confirmed previously proposed hydroxylation and bond-cleavage pathways and further identified additional hydroxylated intermediates formed on the thiazole and benzene rings under NTP conditions, and (iii) energy evaluation through energy per order (EEO) within a single, reproducible operating window. The EEO values for SMZ and STZ degradation via NTP were calculated at 22.4 and 7.5 kWh/m3/order, respectively. These values are up to 37- and 118-fold lower than those reported for comparable AOPs, quantitatively confirming that the proposed NTP process achieves superior energy efficiency for sulfonamide degradation. Degradation is primarily attributed to reactive oxygen species (ROS) generated by plasma, which initiate the breakdown of the antibiotic structure. Overall, this study demonstrates that NTP is a highly effective AOP for driving the rapid primary degradation and intermediate structural transformation of recalcitrant sulfonamide antibiotics. Full article
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22 pages, 3745 KB  
Article
Molecularly Imprinted Polymer with Photocatalytic Activity for the Adsorption and Degradation of Naproxen and Its Application in Real Water Samples
by Diana Samantha Villarreal-Lucio, Karla Ximena Vargas-Berrones, Brenda V. Loera-García, Vanessa Sarahí Galván-Romero, Carolina López-Saldaña, Raúl Ocampo-Pérez, Héctor Hernández-Mendoza and Rogelio Flores-Ramírez
Separations 2026, 13(4), 121; https://doi.org/10.3390/separations13040121 - 17 Apr 2026
Viewed by 181
Abstract
This research focused on the development and characterisation of molecularly imprinted polymers (MIPs) modified with titanium dioxide (TiO2) for the adsorption and photocatalytic degradation of sodium naproxen (NPX). Different percentages of TiO2 (5% and 25%) were tested and compared to [...] Read more.
This research focused on the development and characterisation of molecularly imprinted polymers (MIPs) modified with titanium dioxide (TiO2) for the adsorption and photocatalytic degradation of sodium naproxen (NPX). Different percentages of TiO2 (5% and 25%) were tested and compared to non-imprinted polymers (NIPs). FT-IR analysis confirmed the interaction between methacrylic acid and TiO2, promoting the formation of specific binding sites and presenting a good imprinting factor. The results showed that the MIP with 5% TiO2 had the highest adsorption and retention capacity, attributed to the imprinting effect and the reduced interference from TiO2. The surface of the MIPs is heterogeneous, as it was indicated by the Freundlich isotherm model. The KF for the MIP with 25% of TiO2 was higher than for the materials with 5%; values for the MIP/TiO2 5% and the NIP/TiO2 5% KF were 4.808 and 4.163 (mg/g)(L/mg)1/n respectively, while for the MIP/TiO2 25% was 6.542 (mg/g)(L/mg)1/n and for the NIP/TiO2 25% it was 2.736 (mg/g)(L/mg)1/n. Kinetic studies followed the pseudo-second-order model, suggesting more active binding sites in MIPs. Photocatalytic experiments achieved 60% degradation, demonstrating the degradation performance of MIPs; however, this behavior is restricted by the slow degradation of NPX. The materials were evaluated using a water sample (Querétaro River, México); the sample was preconcentrated and analyzed, detecting a concentration of 0.332 mg/L of NPX. This finding highlights the MIPs’ potential application in environmental monitoring and treatment; nevertheless, due to the recalcitrant nature of NPX, MIPs should be used along with other advanced treatment methods to achieve effective removal. Full article
(This article belongs to the Special Issue Molecularly Imprinting Polymers for Separation and Detection)
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12 pages, 1006 KB  
Article
Molecular Characterization and Preliminary NGS Profiling of Terbinafine-Resistant Trichophyton indotineae Isolates in Italy
by Deborah Cruciani, Manuela Papini, Luigi Pisano, Roberta Calcaterra, Donatella Pietrella, Tommaso Galeotti, Paolo Fazii, Antonia Meloscia, Martina Torricelli, Marco Di Domenico, Alessandro Fiorucci, Sara Spina and Silvia Crotti
Pathogens 2026, 15(4), 435; https://doi.org/10.3390/pathogens15040435 - 17 Apr 2026
Viewed by 141
Abstract
Trichophyton indotineae is an emerging dermatophyte associated with extensive, chronic, recalcitrant, and frequently terbinafine-resistant dermatophytosis worldwide. In this study, 30 T. indotineae strains isolated in Italy were investigated. The isolates were obtained from patients originating from Asian countries, from patients from other countries, [...] Read more.
Trichophyton indotineae is an emerging dermatophyte associated with extensive, chronic, recalcitrant, and frequently terbinafine-resistant dermatophytosis worldwide. In this study, 30 T. indotineae strains isolated in Italy were investigated. The isolates were obtained from patients originating from Asian countries, from patients from other countries, and from Italian patients who reported no travel outside Italy in the preceding years. Clinical isolates were identified by internal transcribed spacer (ITS) sequencing and analyzed to assess the occurrence and molecular basis of terbinafine resistance. Terbinafine resistance was detected in 18 strains (60%) using a real-time PCR assay. Sequencing of the squalene epoxidase (SQLE) gene revealed mutations associated with resistance, including L393S in nine strains and F397L in another nine strains. NGS analysis confirmed two terbinafine-resistant strains carrying the L393S and F397L mutations, respectively, and detected the A448T mutation in one terbinafine-susceptible strain. These findings demonstrate the presence of terbinafine-resistant T. indotineae across five regions of Italy and confirm the occurrence of SQLE mutations previously linked to antifungal resistance. Data obtained also support a link with endemic Asian areas, other than suggesting the possible occurrence of autochthonous transmission in Italy. Full article
(This article belongs to the Special Issue Epidemiology and Molecular Detection of Emerging Fungal Pathogens)
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41 pages, 4060 KB  
Review
Reimagining Textile Effluent Treatment Using Metal–Organic Framework-Based Hybrid Catalysts: A Critical Review
by Hossam A. Nabwey and Maha A. Tony
Catalysts 2026, 16(4), 355; https://doi.org/10.3390/catal16040355 - 15 Apr 2026
Viewed by 338
Abstract
Textile wastewater remains one of the most challenging industrial effluents to remediate due to its intense and persistent coloration, high organic load, elevated salinity, and fluctuating pH and the presence of recalcitrant dye structures and auxiliary chemicals. Conventional physicochemical and biological treatments frequently [...] Read more.
Textile wastewater remains one of the most challenging industrial effluents to remediate due to its intense and persistent coloration, high organic load, elevated salinity, and fluctuating pH and the presence of recalcitrant dye structures and auxiliary chemicals. Conventional physicochemical and biological treatments frequently achieve incomplete removal, generate secondary wastes, or fail under high-salt and toxic dye matrices. Advanced oxidation processes (AOPs) provide molecular-level degradation via reactive oxygen species (ROS), yet their deployment is often constrained by narrow operating windows, catalyst instability, chemical/energy demand, and scale-up limitations. In this context, metal–organic frameworks (MOFs) have emerged as tunable porous catalytic platforms that integrate adsorption and oxidation within a single architecture through controllable metal nodes, functional linkers, and engineered pore environments. This critical review reimagines textile effluent treatment through the lens of MOF-based hybrid catalysts, synthesizing progress across Fenton/photo-Fenton catalysis, photocatalytic MOFs, persulfate activation, and MOF-derived/composite systems. Mechanistic pathways are discussed by linking pollutant enrichment, cyclic redox reactions, charge-transfer processes, and ROS-driven degradation toward mineralization, with emphasis on the distinction between rapid decolorization and true organic removal. A critical comparison highlights how hybridization improves charge transport, stability, and catalyst recovery, while persistent gaps remain in hydrolytic robustness, metal leaching control, intermediate toxicity assessment, real-wastewater validation, continuous-flow reactor integration, and techno-economic feasibility. Finally, the review outlines actionable research directions, including water-stable and defect-engineered MOFs, immobilized and structured catalysts, solar-driven operation, standardized performance metrics, and life-cycle-informed design, to accelerate translation toward scalable and sustainable textile wastewater remediation. By bridging material chemistry with reactor-level feasibility and sustainability assessment, this review provides an implementation-oriented perspective for next-generation textile wastewater treatment. Full article
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23 pages, 7254 KB  
Article
Photocatalytic Cleanability of ZnO-Decorated Ceramic Membranes for Rhodamine B Removal
by Yassine Khmiri, Feryelle Aouay, Afef Attia, Hajer Aloulou, Lasâad Dammak, Catia Algieri and Raja Ben Amar
Membranes 2026, 16(4), 148; https://doi.org/10.3390/membranes16040148 - 14 Apr 2026
Viewed by 415
Abstract
The widespread presence of stable and hazardous organic contaminants, such as synthetic dyes, in industrial effluents necessitates the development of resilient treatment strategies capable of achieving efficient degradation and decolorization of dye pollutants. Conventional treatment processes often fail to remove such recalcitrant compounds, [...] Read more.
The widespread presence of stable and hazardous organic contaminants, such as synthetic dyes, in industrial effluents necessitates the development of resilient treatment strategies capable of achieving efficient degradation and decolorization of dye pollutants. Conventional treatment processes often fail to remove such recalcitrant compounds, prompting growing interest in integrated advanced systems. Photocatalytic membranes represent a promising solution due to the synergistic combination of physical separation and catalytic degradation. In this study, zinc oxide (ZnO) thin films were deposited by spin coating onto smectite–zeolite ceramic membranes (MS10/Z90), applying one (M1), two (M2), and three (M3) successive coating layers to control catalyst thickness. SEM analysis confirmed that increasing the number of layers resulted in a thicker and more homogeneous ZnO coating, while XRD revealed enhanced crystallinity and larger crystallite size. Water permeability decreased progressively from 623 L·h−1·m−2·bar−1 for the uncoated membrane to 506, 439, and 350 L·h−1·m−2·bar−1 for M1, M2, and M3, respectively. Photocatalytic performance was evaluated using Rhodamine B (RhB) (10 mg·L−1) under UV irradiation (365 nm, 18 W) for 180 min, achieving degradation efficiencies of 83.0%, 94.6%, and 99.1% for M1, M2, and M3, respectively. The degradation kinetics followed a pseudo-first-order model, with rate constants increasing with catalyst layer thickness. Free radical scavenging assays confirmed that hydroxyl radicals (•OH) were the primary reactive species responsible for RhB degradation. These findings highlight the critical influence of ZnO layer thickness and mass transfer on photocatalytic performance, demonstrating the potential of ZnO-coated ceramic membranes for efficient pollutant degradation and in situ photocatalytic regeneration. Permeability measurements after photocatalytic treatment confirmed effective flux recovery, supporting the operational durability of the developed membranes. Full article
(This article belongs to the Section Membrane Applications for Water Treatment)
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18 pages, 1060 KB  
Review
Adoptive Cell Therapies for Glioblastoma: A Quest for Cures from Within
by Jia-Shiun Leu, Xin Ge, Charles Robin Yu, Guang Peng and Jiyong Liang
Biology 2026, 15(8), 614; https://doi.org/10.3390/biology15080614 - 13 Apr 2026
Viewed by 732
Abstract
Glioblastomas (GBMs) are the most aggressive form of brain cancer recalcitrant to both current standard-of-care and immune checkpoint therapies that benefit other cancer patients. Adoptive cell therapies (ACT) using patients’ own immune cells have long been explored as a treatment strategy, including the [...] Read more.
Glioblastomas (GBMs) are the most aggressive form of brain cancer recalcitrant to both current standard-of-care and immune checkpoint therapies that benefit other cancer patients. Adoptive cell therapies (ACT) using patients’ own immune cells have long been explored as a treatment strategy, including the historically studied lymphokine-activated killer (LAK) cells, the evolving chimeric antigen receptor (CAR) directed immune cells, the newly emerging tumor-infiltrating T lymphocyte (TIL) therapies, and others. Preclinical and clinical studies have shown promise but also highlighted significant challenges. In this review, we summarize these findings, highlight recent developments, discuss current limitations, and emphasize how ACT may benefit from contemporary and future insights into the co-evolution of TILs with other cells within the GBM tumor microenvironment (TME). Full article
(This article belongs to the Section Cancer Biology)
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18 pages, 849 KB  
Article
Use of Denitrifying Sludge for the Removal of Acetaminophen in Water
by Liliana Rodríguez-Flores, César Camacho-López, Claudia Romo-Gómez, Otilio A. Acevedo-Sandoval, Fernando Salas-Martínez, José B. Leyva-Morales and César. A González-Ramírez
Environments 2026, 13(4), 210; https://doi.org/10.3390/environments13040210 - 10 Apr 2026
Viewed by 830
Abstract
Acetaminophen, more commonly known as paracetamol (APAP), is one of the most widely used analgesics and antipyretic drugs worldwide. Its presence in the environment poses a risk to the organisms it comes into contact with, which is why it has been classified as [...] Read more.
Acetaminophen, more commonly known as paracetamol (APAP), is one of the most widely used analgesics and antipyretic drugs worldwide. Its presence in the environment poses a risk to the organisms it comes into contact with, which is why it has been classified as an emerging contaminant. Given its adverse effects and continuous discharge into water bodies, it is necessary to study efficient, environmentally sustainable processes for its complete removal. Denitrification is a biological process that has been studied for the biodegradation of recalcitrant compounds and certain pharmaceuticals such as 17β-estradiol and ampicillin, transforming them into harmless products such as N2 and HCO3. In the present study, the biodegradation of 6 mg L−1 of APAP-C was evaluated through a denitrifying process. Batch experiments were conducted, achieving acetaminophen (APAP) removal efficiencies (EAPAP-C) of 83.3 ± 0.86% and nitrate removal efficiencies (EN-NO3) of 100%. The substrates were predominantly converted into HCO3 and N2, with yields greater than 0.9, while intermediates such as NO2 were observed only transiently during the reaction. At the end of the experimental period, no secondary metabolites were detected, indicating that intermediates did not accumulate to quantifiable levels. Full article
(This article belongs to the Special Issue Advanced Research on the Removal of Emerging Pollutants)
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18 pages, 8588 KB  
Article
Establishment of an Organogenesis-Based Regeneration System and Induction of Somatic Embryogenesis in Catalpa ovata
by Pingan Bao, Xingping Huo, Jingshuang Sun, Guanzheng Qu, Wenjun Ma, Junhui Wang and Ruiyang Hu
Plants 2026, 15(8), 1177; https://doi.org/10.3390/plants15081177 - 10 Apr 2026
Viewed by 471
Abstract
To overcome the seasonal constraints of explant availability and facilitate genetic improvement in Catalpa ovata, this study established a dual-pathway in vitro regeneration system (encompassing adventitious shoot organogenesis and somatic embryogenesis) using mature zygotic embryos. We systematically evaluated the synergistic effects of [...] Read more.
To overcome the seasonal constraints of explant availability and facilitate genetic improvement in Catalpa ovata, this study established a dual-pathway in vitro regeneration system (encompassing adventitious shoot organogenesis and somatic embryogenesis) using mature zygotic embryos. We systematically evaluated the synergistic effects of maternal genotypes, plant growth regulators (PGRs), basal media, and the histone deacetylase inhibitor Trichostatin A (TSA). Genotype screening revealed significant divergence in regenerative potential, with the half-sib family 32F17 exhibiting superior responsiveness (84.7% callus induction). A high cytokinin-to-auxin ratio (ZA3 medium) optimally drove direct shoot organogenesis. For adventitious shoot proliferation, the addition of TDZ significantly improved the multiplication coefficient (up to 2.99 on ZB4 medium), although a physiological trade-off with shoot elongation was observed. In parallel, the application of 10 µM TSA significantly enhanced somatic embryogenesis from embryogenic calli, effectively alleviating the inhibitory constraints of exogenous PGRs. For rhizogenesis, the DKW basal medium proved superior to half-strength MS, with the ZE3 treatment (0.1 mg·L−1 NAA + 0.1 mg·L−1 IBA) yielding the highest rooting frequency (69.6%) and robust root architecture. Notably, while somatic embryo conversion remained recalcitrant, plantlets derived exclusively from the adventitious shoot organogenesis pathway were successfully acclimatized ex vitro. These transplanted plantlets exhibited consistently high survival rates (83.1–84.4%) across all tested genotypes, effectively overcoming the initial genotype-dependent recalcitrance. Collectively, this optimized protocol provides a reliable technical platform for the large-scale clonal propagation and biotechnological breeding of C. ovata. Full article
(This article belongs to the Special Issue Sexual and Asexual Reproduction in Forest Plants—2nd Edition)
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23 pages, 1255 KB  
Review
Solar-Driven Catalytic Wastewater Treatment: A Unified Photonic–Thermal Framework for Advanced Oxidation and Disinfection Mechanisms
by Carlos E. Barrera-Díaz, Bernardo A. Frontana-Uribe, Gabriela Roa-Morales, Patricia Balderas-Hernández and Pedro Avila-Pérez
Catalysts 2026, 16(4), 341; https://doi.org/10.3390/catal16040341 - 10 Apr 2026
Viewed by 482
Abstract
Increasing water demand and the rising complexity of wastewater matrices, driven by pharmaceuticals, personal care products, and recalcitrant industrial contaminants, require advanced catalytic solutions capable of efficient mineralization under sustainable conditions. Solar-driven processes have attracted growing attention; however, ultraviolet disinfection, heterogeneous photocatalysis, and [...] Read more.
Increasing water demand and the rising complexity of wastewater matrices, driven by pharmaceuticals, personal care products, and recalcitrant industrial contaminants, require advanced catalytic solutions capable of efficient mineralization under sustainable conditions. Solar-driven processes have attracted growing attention; however, ultraviolet disinfection, heterogeneous photocatalysis, and photo-Fenton systems are commonly treated as independent approaches without mechanistic integration. This review presents a unified photonic–thermal catalytic framework for solar-driven wastewater treatment, emphasizing the interplay between photon absorption, charge-carrier separation, reactive oxygen species generation, and radical-mediated oxidation pathways. The contributions of ultraviolet, visible, and infrared radiation are analyzed in terms of catalyst activation, persulfate and ozone activation mechanisms, and temperature-enhanced reaction kinetics governed by Arrhenius behavior. Particular attention is given to photothermal effects that modulate surface reaction rates, mass transfer, and catalyst stability. By integrating mechanistic insights with reactor-level considerations, this work provides a rational basis for the design of robust solar catalytic systems with enhanced activity, selectivity, and scalability for real wastewater applications. Full article
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24 pages, 1021 KB  
Systematic Review
Photocatalytic Performance of Modified TiO2: A Comparative Analysis of Doping and Co-Doping Process on Methylene Blue Discoloration
by William Vallejo, Carlos Diaz-Uribe and Edgar Mosquera-Vargas
Sci 2026, 8(4), 86; https://doi.org/10.3390/sci8040086 - 9 Apr 2026
Viewed by 370
Abstract
Heterogeneous photocatalysis is one of the most versatile and widely studied photochemical approaches for the degradation of recalcitrant pollutants. Owing to its favorable physicochemical properties, titanium dioxide (TiO2) remains one of the most investigated semiconductor photocatalysts. However, its wide band-gap energy [...] Read more.
Heterogeneous photocatalysis is one of the most versatile and widely studied photochemical approaches for the degradation of recalcitrant pollutants. Owing to its favorable physicochemical properties, titanium dioxide (TiO2) remains one of the most investigated semiconductor photocatalysts. However, its wide band-gap energy (3.2 eV) restricts its photoactivity to the UV region, which represents only a small fraction of the solar spectrum. A major challenge in this field is therefore the development of TiO2-based materials capable of operating efficiently under visible light irradiation, enabling the use of solar energy as a sustainable primary source. Several strategies have been explored to extend the optical response of TiO2, among which elemental doping remains one of the most effective and commonly applied. In this work, we conducted systematic comparative analysis to evaluate the photocatalytic performance of TiO2 modified through different doping approaches. Sixty-one scientific reports published between 2015 and 2025 were analyzed, comparing three categories of dopants: (i) metal dopants, (ii) non-metal dopants, and (iii) co-doping systems. In the first section, we discuss fundamental concepts of photocatalysis and recent advances in doping strategies and surface modifications aimed at enhancing the photocatalytic performance of TiO2. In the second section, we present a comparative analysis based on 61 scientific reports focusing on TiO2 doping and co-doping processes. Finally, this study summarizes the different categories of doped TiO2 photocatalysts by comparing the photocatalytic performance employing an alternative performance metric. Full article
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18 pages, 2691 KB  
Article
Water-Based Pretreatment Combined with Severity-Optimized Organosolv Enables Near-Complete Enzymatic Hydrolysis of Wheat Straw at Reduced Energy Demand
by Tianyi Guo, David Thielen, Malik Aydin and Nils Tippkötter
Sustain. Chem. 2026, 7(2), 17; https://doi.org/10.3390/suschem7020017 - 3 Apr 2026
Viewed by 281
Abstract
Wheat straw is an abundant agricultural residue with high potential for carbohydrate-based bioconversion, yet its efficient utilization is limited by lignocellulosic recalcitrance. This study systematically investigated Organosolv extraction of wheat straw (Triticum aestivum) with the goal of achieving near-complete enzymatic hydrolysis [...] Read more.
Wheat straw is an abundant agricultural residue with high potential for carbohydrate-based bioconversion, yet its efficient utilization is limited by lignocellulosic recalcitrance. This study systematically investigated Organosolv extraction of wheat straw (Triticum aestivum) with the goal of achieving near-complete enzymatic hydrolysis at minimized process severity and energy demand. Process severity was evaluated using the P-Factor concept. In preliminary screening, acid catalysts and liquor ratios were assessed. Strong acids clearly outperformed weak acids: at comparable severity, 5% (w/w, DM) H2SO4 or p-toluenesulfonic acid (PTSA) yielded glucose yields of 83 ± 2.4% and 81 ± 6.2%, respectively, whereas weak acids (phosphoric, lactic, acetic) and a catalyst-free control resulted in only ~20–41% glucose yield. Liquor ratio strongly affected extraction performance; a ratio of 1:19 provided the highest glucose yield (85 ± 1.4%) and robust mixing compared to 1:12–1:15 (67–68%). Two novel pretreatment strategies applied prior to Organosolv extraction, namely Hot-Water Pretreatment (HWP) and Water Pretreatment (WP), significantly increased hydrolysability compared to untreated straw (58 ± 3%), reaching 79 ± 2% for HWP and 86 ± 5% for WP. DoE-based experiments (135–170 °C; P-Factor 3.0–4.0) showed that increasing temperature from 135 to 150 °C markedly improved hydrolysability (e.g., WP: 74 ± 3% to 96 ± 3%), while further increasing to 170 °C provided no additional benefit. Response-surface modeling predicted a maximum hydrolysability of approximately 88% for HWP but complete hydrolysis for WP within 152–170 °C, indicating a broad operational window. Overall, combining simple Water-based Pretreatment with severity-optimized Organosolv extraction enables energy-efficient, near-complete hydrolysis at lower operating temperatures, reducing both energy demand and pressure requirements, and thereby offering advantages in process cost and scalability. Full article
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23 pages, 1467 KB  
Review
Emerging Contaminants in Wastewater: Mitigation Approaches for Environmental Management and Future Sustainability
by Podila Sujan Sai, Kokkanti Hemanth Kumar, Alapati Nidhi Sri, Ranaprathap Katakojwala, Jagiri Shanthi Sravan and Manupati Hemalatha
Water 2026, 18(7), 860; https://doi.org/10.3390/w18070860 - 3 Apr 2026
Viewed by 673
Abstract
Emerging contaminants (ECs) are a diversely mounting group of chemicals and biological compounds found in air, water, and soil, which include pharmaceuticals, personal care products, per- and poly-fluoroalkyl substances (PFASs), microplastics, endocrine-disrupting chemicals, and various other industrial compounds. Unlike conventional pollutants, ECs are [...] Read more.
Emerging contaminants (ECs) are a diversely mounting group of chemicals and biological compounds found in air, water, and soil, which include pharmaceuticals, personal care products, per- and poly-fluoroalkyl substances (PFASs), microplastics, endocrine-disrupting chemicals, and various other industrial compounds. Unlike conventional pollutants, ECs are usually unregulated, found in very small amounts, and can persist and build up in living organisms, resulting in toxic risks for both ecosystems and human health. These contaminants originate from various anthropogenic activities and enter the environment through wastewater, stormwater, landfill leaching, and atmospheric deposition. This article documents a holistic literature review of ECs available from the last five years, covering classification, sources and pathways of contamination, and environmental behavior, while assessing their ecological, human health, and socioeconomic impacts. Advances in detection, including high-resolution mass spectrometry, non-target screening, real-time sensors, and AI-assisted monitoring, are addressed. Management strategies including advanced oxidation, membrane filtration, electrochemical treatments, and nature-based solutions are explored. It also analyses global and regional policy frameworks, highlighting regulatory gaps and the need for standardized monitoring. The study emphasizes integrated, multidisciplinary approaches combining scientific innovation, sustainable chemical design, predictive modeling, and public engagement. Synergizing technology, governance, and prevention could reduce the risks related to ECs and protect the environment. The novel contribution is an end-to-end, decision-oriented synthesis that links what monitoring can reliably infer to be feasible, integrated control strategies and sustainability outcomes, supporting risk-based prioritization, targeted pollution treatment, and prevention-focused management. Full article
(This article belongs to the Special Issue Rethinking Wastewater: Microbial Solutions for a Sustainable Future)
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18 pages, 1403 KB  
Article
Beyond the C/N Ratio: The Critical Role of Carbon Bioavailability in Aerobic Composting of Agricultural Waste
by Bo Shen, Xiaoyan Zheng, Lili Zheng, Yang Yang, Dao Xiao, Zhanwu Sheng, Yiqiang Wang and Binling Ai
Clean Technol. 2026, 8(2), 46; https://doi.org/10.3390/cleantechnol8020046 - 1 Apr 2026
Viewed by 378
Abstract
The initial carbon-to-nitrogen (C/N) ratio is a fundamental parameter for aerobic composting, with a generally recommended optimal range of 25:1 to 30:1. However, in practical applications, the optimal C/N ratio often deviates from the recommended value. We attribute this discrepancy to the limitations [...] Read more.
The initial carbon-to-nitrogen (C/N) ratio is a fundamental parameter for aerobic composting, with a generally recommended optimal range of 25:1 to 30:1. However, in practical applications, the optimal C/N ratio often deviates from the recommended value. We attribute this discrepancy to the limitations of traditional stoichiometric methods in assessing the bioavailability of carbon and nitrogen sources. This study investigated how carbon bioavailability governs composting efficiency and product quality. Laboratory-scale aerobic composting experiments were conducted using six types of raw crop straws and two physically pretreated straws, representing a biodegradability gradient. Results demonstrated that carbon bioavailability significantly modulated the composting performance. Substrates rich in labile carbon pool (LCP), such as wheat straw and extruded cassava plant residue, demonstrated superior thermogenesis, humification, and seed germination indices compared to those dominated by recalcitrant carbon pool (RCP), such as untreated cassava plant residue. Principal component analysis confirmed a strong positive correlation between LCP content and key quality indicators. Microbiological analysis revealed that carbon source variations shaped bacterial succession: Bacteroidota abundance correlated positively with LCP, driving rapid initial degradation, whereas Pseudomonadota were more abundant in RCP-rich treatments, suggesting a role in complex polymer breakdown. This study confirmed that carbon bioavailability, rather than the bulk C/N ratio alone, is a critical limiting factor. This finding logically extends to the role of nitrogen bioavailability, suggesting that a “biochemical C/N ratio”—accounting for the lability of both carbon and nitrogen—could be a more accurate predictor of aerobic composting performance. Full article
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26 pages, 3042 KB  
Article
Mechanistic DFT Insights into Mn-Porphyrin Quantum Catalysts for Peroxymonosulfate-Driven Degradation of Sulfamethoxazole in Water
by Mohammad Oves
Catalysts 2026, 16(4), 298; https://doi.org/10.3390/catal16040298 - 31 Mar 2026
Viewed by 411
Abstract
Emerging pharmaceutical contaminants, including sulfonamide antibiotics such as sulfamethoxazole (SMX), persist in natural water bodies at ng L−1 to µg L−1 concentrations and are inadequately removed by conventional wastewater treatment technologies, posing significant ecological and public health risks. Porphyrin-based quantum catalysts [...] Read more.
Emerging pharmaceutical contaminants, including sulfonamide antibiotics such as sulfamethoxazole (SMX), persist in natural water bodies at ng L−1 to µg L−1 concentrations and are inadequately removed by conventional wastewater treatment technologies, posing significant ecological and public health risks. Porphyrin-based quantum catalysts activated by peroxymonosulfate (PMS) represent a promising advanced oxidation strategy for the remediation of such recalcitrant micro-pollutants. However, the precise molecular mechanisms governing their catalytic activity remain incompletely understood. In this study, we present a comprehensive mechanistic investigation of SMX oxidation catalyzed by Mn (III) meso-tetraphenylporphyrin (Mn-TPP) in the presence of PMS, employing spin-unrestricted density functional theory (DFT) at the Becke, 3-parameter, Lee–Yang–Parr (B3LYP-D3BJ) level of theory with dispersion corrections. Full Gibbs free energy profiles for the catalytic cycle were constructed through geometry optimizations using the LACVP basis set on Mn and 6-31G(d,p) on all non-metal atoms, followed by single-point energy calculation at the 6-311+G(d,p) level, incorporating the SMD implicit solvation model to stimulate aqueous environment conditions. The results demonstrate that the oxidation of Mn TPP by PMS to generate the key high-valent intermediate Mn(V)=O(TPP)+ is thermodynamically and kinetically favorable. The activation barrier for Mn(V)=O(TPP)+ formation via PMS activation is ΔG† = 17.2 kcal mol−1 (SMD water, 298 K), confirming that this step is kinetically accessible under ambient environmental conditions. Subsequent SMX oxidation processes proceed via concerted radical and non-radical mechanistic pathways, with the most thermodynamically favorable route exhibiting a strongly exergonic reaction-free energy (ΔGr), indicating that significant mineralization of the target pollutant is thermodynamically accessible. The transition state analysis reveals spin density localization characteristic of the Mn-Oxo species, establishing a direct correlation between quantum confinement effects, electronic structure and the observed catalytic selectivity and oxidation stability of the Mn-TPP system. These mechanistic insights provide quantitative molecular-level design parameters, including activation barriers, spin state requirements, and electronic structure descriptors for the rational optimization of next-generation porphyrin-based quantum catalysts capable of efficiently degrading persistent pharmaceutical contaminants in complex aqueous matrices. Full article
(This article belongs to the Special Issue Novel Catalytic Techniques for Reducing Organic Pollutants)
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30 pages, 3972 KB  
Article
Screening and Optimization of Metal–Chelate Activated Persulfate for Degradation of Persistent Dyes: Evaluation of UVC, Solar Light, and Ultrasound Assistance
by Karima Bellir, Slimane Merouani, Haroune Bouchelaghem and Amel Riah
Processes 2026, 14(7), 1125; https://doi.org/10.3390/pr14071125 - 31 Mar 2026
Cited by 1 | Viewed by 401
Abstract
Chelating agents can extend the operational pH range of iron-based advanced oxidation processes, yet comprehensive studies on chelated Fe-activated persulfate systems for textile dye degradation remain scarce. This study establishes an integrated framework for optimizing Fe(II)/persulfate (PS) systems using chelating ligands and hybrid [...] Read more.
Chelating agents can extend the operational pH range of iron-based advanced oxidation processes, yet comprehensive studies on chelated Fe-activated persulfate systems for textile dye degradation remain scarce. This study establishes an integrated framework for optimizing Fe(II)/persulfate (PS) systems using chelating ligands and hybrid energy inputs under near-neutral conditions. Among the tested systems, Fe(II)/PS complexed with citric acid (CA) exhibited superior performance, achieving ~91% dye removal within 20 min at pH 6.5 under optimized conditions (1.25 mM Fe(II), 10 mM PS, 0.1 mM CA). Chelation stabilized Fe redox cycling and prevented precipitation, enabling effective catalysis across pH 3–10. Optimal CA/Fe and Fe/PS ratios (0.1:1.25 and 1.25:10) yielded ~96% decolorization and 67.65% TOC removal in 60 min, while excessive chelation reduced activity. Transition metal screening (Mn(II), Zn(II), Cu(II), Co(II), and Ni(II) confirmed Fe(II) as the most effective activator, providing removal efficiencies up to 3.2-fold higher than competing metals. Mixed-dye experiments showed competitive degradation, with >37% color removal after 60 min for ternary dye mixtures. Mineralization reached ~92% TOC reduction after 120 min, indicating deep oxidation beyond chromophore cleavage. Reactive species quenching revealed a mixed oxidation mechanism involving OH radicals and high-valent Fe(IV) species. Hybrid assistance improved mineralization, with UVC increasing TOC removal by 15.6%, while solar irradiation provided moderate enhancement under low-energy input. In contrast, low-power ultrasound (40 kHz, 60 W) delivered only 17.6 W acoustic power to the solution and did not improve performance due to limited cavitation and mixing. This work thus contributes a robust platform for advancing chelated iron-persulfate oxidation systems toward practical, effective treatment of recalcitrant dye-contaminated wastewaters under near-neutral conditions. Full article
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