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[Display omitted] • The aging process of MPs and characteristics of aged MPs. • The aging process significantly changed the physicochemical characteristic of MPs. • The additives and intermediates released from aging process of MPs. • Temperature, pH, salinity and light had certain effects on the release of MPs. • Aged MPs and release of aging led to potential risks on organisms. Microplastics (MPs) have attracted significant concern due to their persistence and adverse effects on organisms. In this review, we summarize the recent literature on the natural and artificial aging process of MPs, and also discuss the associated aging characteristics and mechanisms of MPs. The aged MPs show different morphological and chemical properties from the pristine MPs. Furthermore, to evaluate associated aging effects, the corresponding release of aging process of MPs were systematically evaluated, including the additives and intermediates. Different types of organic pollutants and heavy metals additives are listed. In addition, the release of MPs is affected by environmental factors (i.e., Illumination, salinity, temperature and pH). Aged MPs are more easily absorbed by organisms and have different toxic effects from the pristine MPs. The potential risks of aging MPs and the release of MPs during aging are discussed in detail. This overview provides a direction for further study on the behavior and the toxic effects of MPs in the environment. [ABSTRACT FROM AUTHOR]

High-quality perovskite polycrystalline thin films are generally achieved through antisolvent-assisted crystallization, a crucial process that facilitates desolvation. However, antisolvent method is limited by issues of toxicity and fabrication complexity. Here, we introduce a "binary volatile additive" strategy using methylammonium chloride (MACl) and trifluoroacetamide (TFAA) in dimethylformamide/N-methyl-2-pyrrolidone co-solvent system, enabling end-to-end management of antisolvent-free crystallization process. Combining in-situ characterizations and DFT calculations, we prove that TFAA adjusts coordination with perovskite intermediates, facilitating solvent removal and promoting the formation of nuclei, while MACl reduces the formation energy of α-phase formamidinium-based perovskite. Moreover, TFAA not only releases the residual strain caused by MACl, but also in combination with MACl, synergistically widens crystallization window and regulates ripening process, allowing for precise fabrication of homogeneous perovskite films with suppressed defects. By employing the "binary volatile additive" approach, we achieve perovskite solar cells with a power conversion efficiency up to 22.4% and elongated storage life (93% PCE retention over 1000 hours). Our study offers a simple and sustainable approach to produce high-quality perovskite films without the acquisition of antisolvent, streamlining the fabrication process. [Display omitted] • Introduction of 'binary volatile additives' widens crystallization window, promotes high-quality perovskite films, increasing PCE to 22.4%. • DFT calculations and characterizations reveal intermediate interactions, connecting crystallization window expansion with molecular dynamics. • Binary additives offer synergistic benefits and offset weaknesses, enhancing stability—maintaining >90% of initial PCE after 1000 hours at 35±5% RH, unencapsulated. [ABSTRACT FROM AUTHOR]

In this study, a series of Pd/CeO 2 catalysts were synthesized, characterized, and evaluated for the activation of persulfate and the degradation of the micropollutant, bisphenol A (BPA). The efficiency followed a volcano-type behavior with respect to Pd loading, and the 0.25% wt. Pd/CeO 2 exhibited the highest catalytic activity. However, this activity strongly depended on the operating conditions. The system was able to degrade 500 μg/L BPA in less than 30 min, and the removal was favored at near neutral pH (6.2). Scavenging experiments highlighted the role of superoxide and singlet oxygen, followed by sulfate radicals. The efficiency was found to be stable across several cycles, despite a slight decrease in the first cycle. The removal of BPA decreased with the complexity of the water matrices, showing the need for system optimization under real conditions. Five transformation products were identified using UHPLC/TOF-MS and their ecotoxicity was estimated using ECOSAR. Intriguingly, the system was capable of inactivating 99.99% of 2.4 × 105 CFU/mL E. coli , in less than 210 min making it an appealing alternative technology for the simultaneous inactivation of pathogens and degradation of micropollutants in environmental systems. [Display omitted] • The activation of persulfate by Pd/CeO2 showed superior efficiency in degrading BPA. • BPA decomposition occurs through both radical and non-radical mechanisms. • Five transformation products were identified using UHPLC/TOF-MS. • 99.99% of 2.4 × 10^5 CFU/mL E. coli were inactivated in less than 210 min. [ABSTRACT FROM AUTHOR]

In recent years, bisphenol A has been progressively replaced by other bisphenol analogues, leading to an increase of their occurrence in aquatic environments. However, limited data is available regarding their removal through oxidation treatments, such as ozonation. In this work, the reactivity of ozone with seven novel bisphenol A substitutes (bisphenol E, bisphenol B, bisphenol AF, bisphenol C, bisphenol AP, bisphenol Z and bisphenol C-Cl) was studied over a wide range of pH by competition kinetics. The second-order rate constants of ozone were determined for their protonated species (k 1 , k 2 and k 3), together with their pH-dependent reactivity profile. High and similar reactivity of ozone with all bisphenols was distinguished at basic pH (k 3 = 8.83×108 - 1.39×109 M−1 s−1). This reactivity decreased at neutral pH, although it remained comparable for all bisphenols (k app = 2×106 - 5×106 M−1 s−1). In contrast, the even lower reactivity observed at acidic pH exhibited significant variations between them (k 1 = 1.54×102 - 1.22×105 M−1 s−1), due to the influence of the different functional groups, as their behaviour as electron-donating or electron-withdrawing moieties strongly govern their reactivity with ozone. Additionally, the oxidation products resulting from the reaction of ozone with bisphenols at neutral pH were also assessed. The generation of catechol derivatives was suggested as the primary degradation pathway for the majority of bisphenols. Other oxidation products were also commonly detected, such as ortho -quinone derivatives, ring opening products and simple phenolic fragments. [Display omitted] • Ozone rate constants with protonated species of 7 novel bisphenols were determined. • pH dependence of O 3 reactivity with bisphenol analogues was distinguished. • Significant differences of O 3 reactivity with bisphenols were observed at acidic pH. • Catechol and ortho-quinone derivatives were identify as main byproducts. [ABSTRACT FROM AUTHOR]

In plastic, a 2-(2H-benzotriazol-2-yl)-4,6-di-tert-pentylphenol (UV328) ultraviolet light absorber is a common additive. When using sodium hypochlorite (NaClO) to disinfect plastic, UV328 may react with NaClO. For this work, we investigated the transformation behavior of UV328 in polyethylene (PE) plastic by NaClO. The reaction rate increased with the initial free active chlorine (OCl−) concentration and the decrease of the initial UV328 concentration. At room temperature (25 °C) to lower temperatures (0 °C), OCl− could transform UV328, and the reaction activation energy was fitted as 31.10 kJ/mol. Replacement of the plastic carrier (change to polypropylene) had no effect on the reaction process. A total of 12 intermediates were identified, and calculations based on density functional theory (DFT) were used to assist in rationalizing the product structure. Chlorination, hydroxylation, coupling, and bond cleavage were speculated as the main transformation pathways. Dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA) were the only two measured disinfection by-products in the system, and their concentration were 18.33 and 18.19 μg/g, respectively. The toxicity prediction by Toxicity Estimation Software Tool (T.E.S.T) illustrated that the toxicity of the transformation products was higher overall than that of UV328 during the reaction. This work can help to deepen the understanding of the transformation behavior of UV328 in PE plastic in NaClO solution. [Display omitted] • The reaction between NaClO and UV328 at 0 °C can still proceed. • Chlorination, hydroxylation, coupling, and bond cleavage were the main pathways. • The toxicity of products were higher than UV328 according to T.E.S.T. [ABSTRACT FROM AUTHOR]

The incorporation of various types of crop straw to agricultural soils has long been practiced to improve soil fertility. However, the effects of crop straw on the fate of organo-chlorine pesticides in flooded paddy soils are not well understood. The dechlorination of pentachlorophenol (PCP) in four vertical profiles (0-10, 10-20, 20-30, 30-50 mm depth) of two flooded paddy soils, a Plinthudult (Soil 1) and a Tropudult (Soil 2) was investigated following the application of four crop straws (rice, wheat, rape and Chinese milk vetch) to them. In all treatments, PCP dechlorination decreased with increasing soil depth. In the crop straw treatments, PCP was almost completely dechlorinated within 60 days, and rapidly transformed to 2,3,4,5-tetrachlorophenol, and further to 3,4,5-trichlorophenol. Further dechlorination of 3,4,5-trichlorophenol also occurred in all treatments except for the rape straw. It is possible that the NH 4 + and NO 3 − derived from the straw are responsible for the inhibition of the 3,4,5-trichlorophenol dechlorination. The reduction of Fe (III) and SO 4 2− increased following application of the crop straws. The RDA analysis indicated that the Fe (III) reducing bacteria might be involved in the ortho-dechlorination, while SO 4 2− reducing bacteria were involved in para- and meta-dechlorination of PCP. The complete detoxification of PCP depended upon both the crop straw type and soil properties. [ABSTRACT FROM AUTHOR]

Bisphenol A (BPA), a suspected endocrine disruptor, can modify normal plant growth and development. Photosynthesis provides material and energy for the growth and development of plants, in which chlorophyll (Chl) plays a significant role. Many studies have shown that the growth and metabolism of plants vary at different growth stages. Thus the sensitivity of plant's responses to environmental pollution is correspondingly different. We studied the effects of BPA on the Chl contents of soybean ( Glycine Max L.) at different growth stages (seedling, flowering and podding, seed-filling and maturation) by measuring the contents of essential intermediates (5-aminolevulinic acid, porphobilinogen, protoporphyrin IX, magnesium protoporphyrin and protochlorophyll) and the activities of key enzymes (5-aminolaevulinic acid dehydratase, porphobilinogen deaminase, uroporphyrinogen III synthase, magnesium chelatase) in chlorophyll synthesis. Low-dose (1.5 mg/L) BPA exposure increased the activities of key enzymes in addition to the contents of intermediates in Chl synthesis at different growth stages, resulting in increases in Chl contents and net photosynthetic rate. In contrast, medium and high-dose (17.2, 50.0 mg/L) BPA exposure produced inhibitory effects on the indices. Following the withdrawal of BPA exposure, the indices recovered to a degree that was related to the plant growth stage. The effect level (high to low) of BPA on these indices at different growth stages was: seedling stage > maturation stage > flowering and podding stage > seed-filling stage. The reverse effect was observed following the withdrawal of BPA exposure. The responses of key enzymes in plant Chl synthesis to BPA illustrate how BPA affects Chl contents. The effects of BPA show clear differences at different plant growth stages. [ABSTRACT FROM AUTHOR]

Mycoremediation of textile effluents is a practical and eco-friendly approach for mineralizing synthetic dyes. The textile, food processing, chemical, leather, dyestuff, dyeing, and pharmaceutical industries discharge significant amounts of effluents including different types of dyes. One of the largest manufacturers of dyes is the textile industry, and dyes discharged from these industries directly affect the natural ecosystem by entering in to the soil and water. These industries release effluents that are carcinogenic and pose a potential threat to flora and fauna. Distinct fungal species are identified as dye decomposers because these can produce a variety of extracellular enzymes involved in catabolism. The strain isolated from the dye effluents was identified as Lentinus squarrosulus AF5 and had a remarkable ability for decolorization (50–96 %) within 72 h using a dye mix consisting of AB10B, RB5, and RB160 (500 mg L-1. The dynamics of the protein profile was deciphered using gel-free/label-free nLC-MS/MS analysis. Distinct protein profiles in the mycelial extract of Lentinus squarrosulus AF5 were observed following exposure of the strain with dyes mix. About 90 proteins have been depicted by proteomic analysis wherein 10 proteins appear to be differentially expressed during dye treated conditions. Secretome proteome had denoted 13 proteins under similar conditions. Notable levels of manganese peroxidase (258.84 ± 0.001 U/ml) along with relatively lower levels of lignin peroxidases (194.98 ± 0.002 U/ml) and laccase (134.33 ± 0.007 U/ml) were detected during dye treated condition, suggesting thereby the extracellular peroxidases displaying a pivotal role in decolorization process. The UV-Visible, FTIR spectroscopic along with HPLC and LC-QTOF-MS analyses of the dye supernatants following incubation with Lentinus squarrosulus AF5 had indicated the degradation of the dyes. These observations suggest Lentinus squarrosulus AF5 to be a potential strain for the catabolism of azo dyes. [Display omitted] • Lentinus squarrosulus AF5 showed notable dye decolorization ability for mixed dyes. • Mixed dyes showed ∼96% of decolorization was achieved after 72 h of incubation. • The dynamics of the protein profile were deciphered by nLC-MS to identify upregulated molecular factors. • MnP and LiP, Lac were the major extracellular peroxidases in the decolorization process. • LC-QTOF-MS analysis was used to identify the degraded products of azo dyes. [ABSTRACT FROM AUTHOR]

The design of visible–light–driven photocatalysts has been rapidly developed due to the great application potential in environmental pollution remediation. The present work focused on the construction of a novel ternary g–C 3 N 4 /Bi 2 MoO 6 /CeO 2 nanocomposite and the application for photocatalytic removal of 4–CP under irradiation. The g–C 3 N 4 /Bi 2 MoO 6 /CeO 2 photocatalysts were successfully synthesized by a facile solid–state thermolysis assisted ultrasonic dispersion to introduce g–C 3 N 4 nanosheets into Bi 2 MoO 6 /CeO 2 composite. Morphology characterization revealed that the Bi 2 MoO 6 /CeO 2 spherical structure uniformly dispersed on the g–C 3 N 4 nanosheets and the close interface contact induced the generation of dual Z–scheme heterojunction. The as–prepared photocatalysts shown enhanced catalytic activity in comparison with binary Bi 2 MoO 6 /CeO 2 composites and the optimal CBC–20% exhibited the highest degradation efficiency of 99.1% for 4–CP under 80 min illumination, which was attributed to the efficient separation of photogenerated e−–h+ pairs under the dual Z–scheme charges transfer mode. Additionally, combined with trapping experiments and EPR analysis, 4–CP was decomposed mainly by the active species •O 2 − and h+ with a marginal assistance of •OH during the photocatalytic process. The intermediates for 4–CP degradation were analyzed and a reasonable degradation pathway was proposed. [Display omitted] • A novel ternary g–C 3 N 4 /Bi 2 MoO 6 /CeO 2 heterojunction was successfully fabricated. • The composite exhibited superior photocatalytic removal rate of 99.1% for 4–CP. • The enhanced activity was attributed to the dual Z–scheme charges transfer mode. • The degradation pathway was analyzed and mineralization efficiency reached 74.7%. [ABSTRACT FROM AUTHOR]

Due to the increased emission of nitrogen oxides (NO x) from flue gas and its high polluting effects on human health and the ecosystem, much attention is directed toward NO x monitoring, removal, and control. This work reviews the latest progress in NO x photocatalytic removal emphasizing the advancements in surface/interface engineering of photocatalytic materials considering the reaction mechanism and modifications for controlling the generation of the toxic intermediate. Defect chemistry, facet controlling, and stability of the photocatalytic systems are comprehensively discussed. The challenges/bottlenecks of the practical applications are also highlighted at the end. Indeed, the photocatalytic removal of NO x is still a significant challenge due to the remaining limitations. Herein, state of the art in utilizing the widely-used semiconducting materials such as TiO 2 and g-C 3 N 4 -based photocatalysts are summarized, focusing on the eminent strategies to amend their performances under visible light. Also, we briefly survey the utilization of MOFs for NO x photoreduction, highlighting the unlikeness of such materials concerning the coincidence of the organic linkers as light sensitizers and the metallic nodes to intensify the transfer of photoinduced electrons. In addition to the concerns mentioned above in this review, so far, no serious consideration has been paid to the control of toxic by-products and intermediate species generation through NO x removal methodologies. Eventually, this report has been concluded with a summary and some perspectives on the advanced pathways to develop novel efficient nanomaterials for the removal of NO x hazards from the environment. [Display omitted] • Recent progresses in photocatalytic NO x removal are reviewed. • Development of the semiconducting materials and reaction mechanisms towards NO x removal are summarized. • The effectual strategies for improved photocatalytic performance on the surface are discussed. • Surface/interface engineering and the stability of photocatalytic systems are described. • Current challenges and future perspectives of the topic are discussed from environmental point of view. [ABSTRACT FROM AUTHOR]

Characterization of amorphous protein aggregates may offer insights into the process of aggregation. Eleven single amino acid mutants of lipase (LipA of Bacillus subtilis) were subjected to temperature‐induced aggregation, and the resultant aggregates were characterized for recovery of activity in the presence of guanidinium chloride (GdmCl). Based on activity recovery profiles of the aggregates, the mutants could be broadly assigned into four groups. By including at least one mutation from each group, a mutant was generated that showed an increase of ~ 10 °C in melting temperature (Tm) compared to the wild‐type and did not aggregate even at 75 °C. This method explores characterization of amorphous protein aggregates in the presence of GdmCl and helps in identifying mutations involved in protein aggregation. [ABSTRACT FROM AUTHOR]

• MnO 2 @(PSS/PDDA) n /PSS was prepared via LBL assembly methods. • The MnO 2 @(PSS/PDDA) 2 /PSS modified anode exhibited efficient OTC degradation. • OH and direct electron transfer mainly contributed to oxidation of OTC. • T.E.S.T calculation and flow cytometry method were used for toxicity assessment. Background: Electrochemical advanced oxidation processes (EAOPs) have received considerable attention due to their ability to transform or mineralize emerging organic contaminants. Methods: Herein, we report that MnO 2 covered with polyelectrolyte films has been fabricated using layer-by-layer (LBL) assembly to modify the anode for efficient oxytetracycline (OTC) oxidation in water. Significant Findings: It is found that over 89.19% of OTC was degraded in 20 min in this EAOPs system with MnO 2 @(PSS/PDDA) 2 PSS modified anode. Quenching experiments and electron-spin resonance (ESR) spectra have shown that hydroxyl radicals (•OH) and direct electron transfer play the dominant roles in OTC oxidation. Several possible pathways of OTC degradation were proposed on the basis of the by-products detected by liquid chromatography-mass spectrometry (LC-MS). Toxicity Estimation Software Tool (T.E.S.T) based on quantitative structure-activity relationships (QSARs) revealed increased toxicity of several transformation products. Moreover, flow cytometry method was applied to quantify the cytotoxic effects of the reaction solution. It may provide an alternative approach to design metal oxide/polymer composites modified anodes for contaminants degradation. It is notable that toxicological assessment of the transformation products is essential especially for newly developed anode materials. [Display omitted] [ABSTRACT FROM AUTHOR]

The objective was to study the degradation of azo dye C.I. Acid Orange 7 (AO7) and intermediates for its synthesis sulphanilic acid (SA) and 2-naphthol (2-N) by Fenton process. Full factorial design and response surface methodology were applied to model the system behavior influenced by studied process parameters ([Fe2+] and [H2O2]). Optimal process conditions were determined on the basis of mineralization efficiency. The effectiveness evaluation of applied treatment process was conducted on the basis of UV/VIS, TOC, COD, BOD5 and toxicity measurements. Fenton reagent ratio 1:62-68 ([Fe2+]≈1.5 mM and [H2O2]=100 mM) yielded the highest TOC reductions for AO7, SA and 2-N (53 %, 44 % and 52 %, respectively), along with the complete decolorization of azo dye solution and degradation of aromatic fragments in solutions after 60-min treatment. Three synthetic wastewaters are characterized as non-biodegradable before Fenton treatment (BOD5/COD≤0.22). After 60-min treatment biodegradability of all three wastewaters was improved; BOD5/COD ratios ranged from 0.38 to 0.52. The values of EC50 showed that all pollutants in investigated concentrations are toxic, while remarkable toxicity reduction after the treatment was noticed only in the case AO7; in the case of other two pollutants the formation of toxic by-products can be assumed. [ABSTRACT FROM AUTHOR]

Abstract: Oxidation of naphthalene (Nap) in supercritical water (SCW) was carried out in a batch reactor (6-ml volume) up to 400°C and 300atm (maximum residence time of 1800s). Two systems were studied. System A consisted of pure naphthalene mixed with oxygen and water: 0.065M Nap+1.441M O2 +8.549M H2O. System B included, in addition to O2 and H2O, a heavy metal and an ash to simulate their roles in the destruction of Nap: 0.065M Nap+1.441M O2 +0.008M Cr(NO3)3 +0.065M Al2Si2O5·(OH)4 +8.624M H2O. It was shown that, in general, the oxidation process can be divided into three stages characterized by H2O2 decomposition to H2O and O2 (Stage 1), oxidation in saturated/subcritical water up to 360°C and 225atm (Stage 2), and fast oxidation in the supercritical region (Stage 3). The oxidation process revealed different reaction rates in different systems. Relatively low activation energy of 10–30kJ/mol was obtained below 360°C and 225atm in the System A and in the whole temperature range in the System B. High activation energy (139.5kJ/mol) was obtained for supercritical water oxidation of naphthalene in the System A. The catalytic effect of Cr3+/ash stimulated naphthalene oxidation. Time-resolved yields of major products and intermediates were obtained. The reaction pattern was proposed. It describes the evolution of naphthalene and intermediates as a sequence of reactions comprising transformations of the main compounds and their inter-conversion. This radical-involving reaction mechanism is mainly based on the quantification of the profiles of the intermediates. [ABSTRACT FROM AUTHOR]

Diethyl phthalate (DEP), as a kind of universally used plasticizer, has aroused considerable public concern owing to its wide detection, environmental stability, and potential health risks. In this work, the highly efficient removal of DEP by ferrate (VI) (Fe(VI)) was systematically explored in soil environment. The effects of the oxidant dosages, soil types, as well as the presence of coexisting cations and anions in tested soil on DEP removal were evaluated. When the dosage of Fe(VI) was 20 mM, complete removal of DEP (50 μg/g) was achieved in the tested soil after 2 min of reaction. Furthermore, the removal rate of DEP was closely related to the soil types, and the degradation rates were decreased obviously in red soil (RS), black soil (BS) and paddy soil (PS), probably due to the acidic condition and high content of organic matters. Moreover, the presence of Ca2+, Mg2+ and Al3+ in soil can inhibit the removal of DEP by Fe(VI), while SO 4 2− has an slightly promotion effect. Six oxidation intermediates were detected in the reaction process of DEP, product analysis revealed that the transformation of DEP was mainly through two pathways, including hydrolysis and hydroxylation reactions, which were probably mediated by oxygen atom transfer process of Fe(VI). Based on the frontier electron density theory calculation, two ester groups of DEP were prone to be attacked by Fe(VI), and the hydroxyl addition tended to occur at the para-position of one of the ester groups on the benzene ring. This study provides a novel approach for phthalate esters removal from soil using Fe(VI) oxidation and shows new insights into the oxidation mechanisms. [Display omitted] • The kinetics of DEP degradation by ferrate (VI) was explored in soil. • Based on product analysis, two degradation mechanisms were proposed. • Ferrate (VI) attacked DEP through oxygen transfer mechanism in pathway. • Theoretical calculations were performed to verify the degradation mechanisms. [ABSTRACT FROM AUTHOR]

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Large-scale contaminated sites with multiple contaminants in the groundwater present a challenge to risk assessment and remediation. Attenuation reactions take place in the subsurface and act to contain contaminants, but must be thoroughly investigated on a site-specific basis. Field data from monitoring wells at a contaminated industrial site in Bitterfeld, Germany, are presented and analyzed for evidence of the prevalent biodegradation reactions. The groundwater in the Tertiary aquifer is contaminated with large quantities of chlorinated aliphatic compounds, in addition to chlorobenzenes and BTEX. In this strictly anaerobic environment, geochemical indications for several microbial processes were found, including methanogenesis, sulfate and iron reduction as well as reductive dechlorination of the chlorinated hydrocarbons. Direct evidence for the latter degradation reaction was observed along the flowpath due to the appearance of intermediates and an increase in the degree of dechlorination. [Copyright &y& Elsevier]

Bicyclic pyrroloimidazolones and pyrrolopyrimidinones were synthesized by reacting aryl-substituted 4-oxobutanoic acids with aliphatic binucleophiles with different alkyl chain lengths using a sealed vessels reactor (SVR). By varying the synthesis conditions, the reaction path was studied and formed intermediates were isolated. The structures of the obtained compounds were proved using a set of FTIR, 1H, 13C NMR spectroscopy methods and X-ray diffraction data. Temperature and pressure changes data collected during the syntheses were analyzed and assigned to the processes which occurred inside the vials. It was shown that the reaction of 4-aryl-4-oxobutanoic acids with terminal aliphatic N,N -diamines starts from the formation of corresponded (AlkN 2)2+An 2 - salts followed by two subsequent dehydration processes giving rise to the corresponding amides and, finally, heterocycles of pyrroloimidazolone and pyrrolopyrimidinone series. [ABSTRACT FROM AUTHOR]

The sulfate radicals (SO 4 •−)-based advanced oxidation process is an efficient way to degrade stubborn pollutants. However, the degradation products of 2,4-dinitrotoluene and the effects of different natural water matrices on 2,4-dinitrotoluene degradation by persulfate/Fe2+ are largely unknown. In this study, the degradation kinetics of 2,4-dinitrotoluene by persulfate/Fe2+ were investigated in different water matrices. The degradation of 2,4-dinitrotoluene can be divided into rapid-slow reaction stages, which was suitably described by the pseudo-first-order kinetics model (R 2 > 0.95). The concentrations of persulfate and Fe2+ had a significant effect on 2,4-dinitrotoluene degradation, and a molar ratio of persulfate/Fe2+ of < 5:1 is favorable for 2,4-dinitrotoluene degradation. Based on the intermediate products, degradation pathways of 2,4-dinitrotoluene, such as hydroxylation/oxidation and removal of the nitro group from the benzene ring, were proposed. The presence of HCO 3 −, CO 3 2−, and NO 3 − inhibited the degradation of 2,4-dinitrotoluene by persulfate/Fe2+. In natural aquatic environments with low Cl− concentrations, the persulfate/Fe2+ oxidation process demonstrated superior efficiency in degrading 2,4-dinitrotoluene. The present results will provide vital information for successfully cleaning up 2,4-dinitrotoluene from the aquatic environment using SO 4 •−-based advanced oxidation process. [Display omitted] • 2,4-dinitrotoluene degradation can be divided into rapid-slow reaction stages. • The molar ratio of persulfate/Fe2+ less than 5 favors 2,4-dinitrotoluene degradation. • The degradation pathways including hydroxylation and the removal of nitro group. • The presence of low concentration Cl− enhanced 2,4-dinitrotoluene degradation. [ABSTRACT FROM AUTHOR]

In this work, a resistant and toxic pesticide called diazinon was degraded through the photoelectrocatalysis (PEC) technique using tungsten oxide (WO 3) nanostructures, applying an external bias of 1V Ag/AgCl and simulated solar illumination. For this, WO 3 nanostructures have been synthesized using electrochemical anodization in 0.05 M hydrogen peroxide and 1.5 M of different acidic electrolytes: H 2 SO 4 , CH 4 O 3 S or HNO 3. Morphology, composition and crystallinity of the samples were evaluated through Field Emission Scanning Electron Microscopy (FE-SEM), Atomic Force Microscopy (AFM) and Raman Spectroscopy. Then, the photoelectrochemical properties of the samples were analyzed by Photo-Electrochemical Impedance Spectroscopy (PEIS). The conclusion obtained with these studies was that the nanostructures obtained in the CH 4 O 3 S-H 2 O 2 electrolyte presented better photoelectrochemical behavior than the others. The degradation process was checked by UV-Visible, and through Ultra High-Performanc liquid Chromatography and Mass Spectrometry (UHPLC-Q-TOF/MS) the courses of the experiments have been controlled and five possible degradation intermediates have been identified. Finally, after 24 h of experiment, 90% degradation efficiency has been achieved, since it has been possible to decrease from 20 ppm to 2 ppm. [Display omitted] • WO 3 nanostructures were synthesized with three different acidic electrolytes. • The nanostructures that have shown the best photoelectrochemical behavior are those obtained with CH 4 O 3 S as electrolyte. • The degradation of diazinon has been carried out using photoelectrocatalysis. • After photoelectrocatalytic degradation of diazinon, 5 possible degradation compounds have been obtained. [ABSTRACT FROM AUTHOR]

The degradation of chlorobenzene in aqueous solution by pulsed power plasma was studied. 100% degradation of 200 mg/L chlorobenzene happened in both liquid and gas phase after 12 min and dechlorination efficiency of 85.3% was obtained after 20 min. The energy efficiency corresponding to 50% chlorobenzene degradation was 3.14 g/kWh. The plasma degradation efficiency of chlorobenzene was inversely proportional to the initial concentration, conductivity and alkalinity of the solution. The study of effect of pH and scavengers on chlorobenzene removal revealed the major role of OH radicals in the degradation. The major intermediate compounds were benzene derivatives including various chlorinated and nitrogenous organics and their concentration decreased significantly after 20 min of plasma treatment. Organic acids such as acetate, formate and oxalate were also produced, which contributed to a part of remaining TOC (total organic carbon) in the solution. The degradation pathway of chlorobenzene involving various oxidative and reductive species is proposed. The disc diffusion test confirmed the complete detoxification of chlorobenzene solution after treatment. [ABSTRACT FROM AUTHOR]

A facile method was applied to achieve complete degradation of oxytetracycline to carbon dioxide and water. In most abiotic degradation, it fails to degrade oxytetracycline to non-toxic products and leaves some intermediates. In this study, sonocatalytic degradation was performed to degrade the more toxic oxytetracycline to less toxic intermediates. In addition, the above intermediates was degraded by biological method, by providing these intermediates as carbon source for bacteria. In the sono degradation process, ZnO was used as sonocatalyst material, which was prepared by simple chemical precipitation method. At first 30 min removal of oxytetracycline was achieved by adsorption and following 30 min will be degraded under ultra-sonication. In addition, sodium peroxydisulfate was used to achieve complete degradation of oxytetracycline. For the best degradation, various parameters such as pH, temperature, dosage of ZnO and concentration of peroxydisulfate, were optimized. At a pH 7, temperature of 55 oC, ZnO dosage of 3 g L-1 and peroxydisulfate concentration of 1 g L-1, the removal efficiency is nearly 99% at the end of 60 min for initial oxytetracycline concentration of 2 ppm. After sonocatalytic degradation, the intermediate formed was naphthalene and was confirmed in this study. Pseudomonas aeruginosa was used for biodegradation of intermediates. This strain is best for using various aromatic compounds as carbon source as it can easily break naphthal rings using naphthalene dehydrogenase enzymes. The removal performance of oxytetracycline and intermediates by sono-bio catalytic degradation was also confirmed by analyzing the total organic carbon (TOC) concentration in the test sample. [ABSTRACT FROM AUTHOR]