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3,5-Dinitrobenzamide has been widely used as a feed additive to control coccidiosis in poultry, and part of the added 3,5-dinitrobenzamide is excreted into wastewater and surface water. The removal of 3,5-dinitrobenzamide from wastewater and surface water has not been reported in previous studies. Highly reactive hydroxyl radicals from UV/hydrogen peroxide (HO) and UV/titanium dioxide (TiO) advanced oxidation processes (AOPs) can decompose organic contaminants efficiently. In this study, the decomposition of 3,5-dinitrobenzamide in aqueous solution during UV/HO and UV/TiO oxidation processes was investigated. The decomposition of 3,5-dinitrobenzamide fits well with a fluence-based pseudo-first-order kinetics model. The decomposition in both two oxidation processes was affected by solution pH, and was inhibited under alkaline conditions. Inorganic anions such as NO , Cl, SO , HCO , and CO inhibited the degradation of 3,5-dinitrobenzamide during the UV/HO and UV/TiO oxidation processes. After complete decomposition in both oxidation processes, approximately 50% of 3,5-dinitrobenzamide was decomposed into organic intermediates, and the rest was mineralized to CO, HO, and other inorganic anions. Ions such as NH , NO , and NO were released into aqueous solution during the degradation. The primary decomposition products of 3,5-dinitrobenzamide were identified using time-of-flight mass spectrometry (LCMS-IT-TOF). Based on these products and ions release, a possible decomposition pathway of 3,5-dinitrobenzamide in both UV/HO and UV/TiO processes was proposed. [ABSTRACT FROM AUTHOR]

The reactivity and fate of parabens during chlorination were investigated in this work. Chlorination kinetics of methylparaben (MeP), ethylparaben (EtP), propylparaben (PrP), and butylparaben (BuP) were studied in the pH range of 4.0 to 11.0 at 25 ± 1 °C. Apparent rate constants ( k ) of 9.65 × 10 M·s, 1.77 × 10 M·s, 2.98 × 10 M·s, and 1.76 × 10 M·s for MeP, EtP, PrP, and BuP, respectively, were obtained at pH 7.0. The rate constants depended on the solution pH, temperature, and NH concentration. The maximum k was obtained at pH 8.0, and the minimum value was obtained at pH 11.0. The reaction rate constants increased with increasing temperature. When NH was added to the solution, the reaction of parabens was inhibited due to the rapid formation of chloramines. Two main transformation products, 3-chloro-parabens and 3,5-dichloro-parabens, were identified by GC-MS and LCMS-IT-TOF, and a reaction pathway was proposed. Dichlorinated parabens accumulated in solution, which is a threat to human health and the aqueous environment. [ABSTRACT FROM AUTHOR]

Degradation of aqueous 3,4-dichloroaniline (3,4-DCA) was conducted in a novel dielectric barrier discharge (DBD) plasma reactor. The factors affecting the degradation efficiency of 3,4-DCA and the degradation mechanism of 3,4-DCA were investigated. The experimental results indicated that the degradation efficiency of 3,4-DCA increased with increasing input power intensity, and the degradation of 3,4-DCA by the novel DBD plasma reactor fitted pseudo-first-order kinetics. Higher degradation efficiency of 3,4-DCA was observed in acidic conditions. The degradation efficiency of 3,4-DCA, the removal rate of total organic carbon (TOC), and the detected Cl increased dramatically with adding Fe or Fe. Degradation of 3,4-DCA could be accelerated or inhibited in the presence of HO depending on the dosage. Several degradation intermediates of 3,4-DCA such as 1,2-dichlorobenzene, 2-chloro-1,4-benzoquinone, 3,4-dichlorophenyl isocyanate, 2-chlorohydroquinone, 3,4-dichloronitrobenzene, and 3,4-dichlorophenol were identified by gas chromatography mass spectrometry (GC-MS) analysis. Based on the identification of aromatic intermediates, acetic acid, formic acid, oxalic acid, and Cl released, a possible mineralization pathway of 3,4-DCA was proposed. [ABSTRACT FROM AUTHOR]

• LDH/GO is synthesized to activate peroxymonosulfate (PMS). • LDH/GO + PMS system shows excellent performance for GAT degradation. • Comparing with LDH, heavy metals dissolving is controlled well in LDH/GO + PMS system. • LDH/GO can be reused many times and maintain effective catalysis. Layered double hydroxide (LDH) was a kind of layer materials with multi-metal elements and good catalytic performance, but the metals can be dissolved during catalysis. Graphene oxide (GO) was a two-dimensional structure with abundant anionic groups with the potential of immobilizing metals. However, LDH combined with GO (LDH/GO) was few reported in the treatment of pharmaceuticals and personal care products (PPCPs). In this work, CoFeNi LDH/GO composites were designed and synthesized for activating peroxymonosulfate (PMS). Meanwhile, gatifloxacin (GAT), a typical antibiotic, was used to assess the performance of LDH/GO + PMS system. The characterization of LDH/GO using various measures showed that the adding GO was inserted the layer structure of LDH and the surface functional group of GO was immobilized in LDH well. GAT could be degraded completely after 45 min under the reaction conditions of pH 7.0, 38 mg L−1 GAT, 40 mg L−1 LDH/GO and 400 mg L−1 PMS. The removal of total organic carbon and defluorination reached 55.5% and 78.0% after 5 h reaction, respectively. Quenching tests suggested that the main radicals responsible for GAT degradation and mineralization was sulfate radical (SO 4 − ). The redox cycle made the catalysis of the LDH/GO composites work continuously. Compared with LDH + PMS system, the concentration of dissolved metals decreased 60.6%-74.3% at pH 3.0–11.0 in LDH/GO + PMS system. The reusability test indicates that LDH/GO has stable catalytic performance in removing PPCPs from wastewater. [ABSTRACT FROM AUTHOR]

In this work, we investigated how different types and concentrations of Lewis acids effect gas yield and composition from supercritical water gasification (SCWG) of dewatered sewage sludge (DSS). Furthermore, the catalytic mechanism was investigated using AlCl 3 as a representative Lewis acid catalyst. Results showed that non-catalytic gasification of DSS produced a hydrogen yield of 0.13 mol/kg organic matter (OM) and total gas yield of 4.82 mol/kg OM; while the addition of 10 wt% Lewis acid resulted in a significantly improved H 2 and total gas yield of 0.77–7.76 mol/kg OM and 7.57–22.88 mol/kg OM, respectively. In addition, the Lewis acids tested herein depicted the following activity trend: AlCl 3 ＞FeCl 3 ＞NiCl 2 ＞ZnCl 2. The required temperature for generating hydrogen from SCWG of DSS was greatly reduced when AlCl 3 was present during the heating process. Furthermore, AlCl 3 significantly increased the hydrogen yield from SCWG of the model compounds. Finally, AlCl 3 catalyzed SCWG of guaiacol and glycerol showed the best hydrogen selectivity. • Effects of different Lewis acid on gas yield and composition were studied. • The hydrogen production increased by 60 times after adding 10 wt% AlCl 3. • AlCl 3 can promote C–C bond breakage and gasification of small molecular organics. • AlCl 3 greatly enhanced the H 2 selectivity of SCWG of guaiacol and glycerol. • AlCl 3 makes the damage and porous morphology of solid surface more evident. [ABSTRACT FROM AUTHOR]

[Display omitted] • High CO 2 /H 2 ratio increased the hydrogen utilization and the denitrification rate. • High CO 2 /H 2 ratio improved the electron transfer activity of sludge. • High CO 2 /H 2 ratio promoted the denitrification and homoacetogenic activity. • Homoacetogenesis – heterotrophic denitrification pathway was established. • Homoacetogens and heterotrophic denitrifying microorganisms were enriched. Hydrogenotrophic denitrification, an environment-friendly process for organic-free influents, is limited due to poor hydrogen mass transfer efficiency and significant pH fluctuations. In this study, we manipulated the carbon dioxide-to-hydrogen ratio to improve hydrogenotrophic denitrification. When carbon dioxide-to-hydrogen ratio was 1:1 (carbon dioxide, 200 ml: hydrogen, 200 ml), the hydrogen utilization and denitrification rates were 2.4 times and 3.0 times that when carbon dioxide-to-hydrogen ratio was 0:1 (carbon dioxide, 0 ml: hydrogen, 200 ml), respectively. The pH fluctuation decreased from 3.1±0.3 to 0.2±0.1. Furthermore, the hydrogenotrophic denitrification, acetoclastic denitrification, homoacetogenic, and electron transfer activities of the sludge were improved. A high carbon dioxide-to-hydrogen ratio augmented the acid-producing and heterotrophic denitrifying microorganism populations. By maintaining a high carbon dioxide-to-hydrogen ratio, the dominant hydrogenotrophic autotrophic denitrification pathway was transformed into a homoacetogenesis-heterotrophic denitrification pathway, thereby achieving higher hydrogen utilization and denitrification rates. [ABSTRACT FROM AUTHOR]

Struvite recovered from wastewater contains high concentration of fecal indicator bacteria (FIB), porcine adenoviruses (PAdV) and antibiotic resistance genes (ARGs), becoming potential resources of these microbial hazards. Understanding the precipitation behavior of pathogenic indicators and ARGs with suspended solids (SS) will provide the possible strategy for the control of co-precipitation. In this study, SS was divided into high-density SS (separated by centrifugation) and low-density SS (further separated by filtration), and the role of SS on the co-precipitation of FIB, PAdV and ARGs was investigated. The distribution analysis showed that 35.5–73.0% FIB, 79.6% PAdV and 64.5–94.8% ARGs existed in high-density SS, while the corresponding values were 26.9–64.4%, 11.7% and 3.5–24.3% in low-density SS. During struvite generation, 82.7−96.9% FIB, 75.5% PAdV and 56.3–86.5% ARGs were co-precipitated into struvite. High-density SS contributed 20.7−68.5% FIB, 63.9% PAdV and 38.7–87.2% ARGs co-precipitation, and the corresponding contribution of low-density SS was 31.4−79.2%, 3.9% and 6.2–54.7%. Moreover, the precipitated SS in struvite obviously decreased inactivation efficiency of FIB and ARGs in drying process. These results provide a potential way to control the co-precipitation and inactivation of FIB, PAdV and ARGs in struvite through removing high-density SS prior to struvite recovery. [Display omitted] Struvite can effectively recover NH 4 +-N and PO 4 3−-P from digested wastewater as a slow-release fertilizer. However, co-precipitation of pathogenic indicators and antibiotic resistance genes (ARGs) during struvite recovery from digested wastewater causes struvite to possess microbial hazards. Most of pathogenic indicators and ARGs are associated with suspended solids (SS) in digested wastewater. Understanding the distribution characteristics of pathogenic indicators and ARGs in SS and the role of SS on the co-precipitation and inactivation will provide the possible strategy for the control of the co-precipitation and inactivation in struvite prior to recovery process. • Suspended solids (SS) was divided into high-density SS and low-density SS. • Distribution of FIB, PAdV and ARGs in the high- and low-density SS was determined. • Co-precipitation of FIB, PAdV and ARGs with struvite formation was quantified. • High-density SS contributed most of the co-precipitated enterococci , PAdV and ARGs. • Precipitated SS in struvite decreased the inactivation efficiency of FIB and ARGs. [ABSTRACT FROM AUTHOR]

Struvite production can recover ammonia and phosphorous from digested wastewater as fertilizer. During struvite generation, most of the heavy metals was co-precipitated with ammonia and phosphorous into struvite. Understanding the precipitation behavior of heavy metals with suspended solids (SS) might provide the possible strategy for the control of co-precipitation. In this study, the distribution of heavy metals in SS and their role on the co-precipitation during struvite recovery from digested swine wastewater were investigated. The results showed that the concentration of heavy metal (including Mn, Zn, Cu, Ni, Cr, Pb and As) ranged from 0.05 to 17.05 mg/L in the digested swine wastewater. The distribution analysis showed that SS with particles > 50 μ m harbored most of individual heavy metal (41.3–55.6%), followed by particles 0.45–50 μ m (20.9–43. 3%), and SS-removed filtrate (5.2–32.9%). During struvite generation, 56.9–80.3% of individual heavy metal was co-precipitated into struvite. The contributions of SS with particles > 50 μ m, 0.45–50 μ m, and SS - removed filtrate on the individual heavy metal co-precipitation were 40.9–64.3%, 25.3–48.3% and 1.9–22.9%, respectively. These finding provides potential way for controlling the co-precipitation of heavy metals in struvite. [Display omitted] • Seven heavy metals, such as Mn, Zn, Cu, Ni, Cr, Pb and As were tested. • 67.1–94.8% of individual heavy metal were distributed in SS. • 56.9–80.3% of individual heavy metal were co-precipitated with struvite formation. • 99.8% reduction in larger-size SS (>50 μ m) concentration after struvite formation. • Larger-size SS (>50 μ m) contributed 40.9–64.3% of individual heavy metal co-precipitation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Acetoclastic methanogenic activity was inhibited by high salinity. • Degradation rate and methane yield of phenol were increased by GAC and H 2. • The syntrophic acetate-oxidizing bacteria were enriched on the GAC surface. • H 2 enhanced hydrogenotrophic methanogenesis pathway. High salinity in phenolic wastewater inhibited anaerobes' metabolic activity, thereby affecting the anaerobic biotransformation of phenol. In this study, granular activated carbon (GAC) coupled with exogenous hydrogen (H 2) was used to enhance the anaerobic digestion of phenol. The GAC/H 2 group's accumulative methane production, coenzyme F 420 concentration, and interspecies electron transfer system activity increased by 24 %, 53 %, and 16 %, respectively, compared with the control group. In the floc sludge of the GAC/H 2 group, the relative abundance of syntrophic acetate-oxidizing bacteria such as Syntrophus and Syntrophorhabdus were 18.7 % and 1.1 % at genus level, respectively, which were around 93.5 and 7.5 times of that of the control group. Moreover, Acinetobacter (77.6 %), Methanobacterium (44.0 %), and Methanosarcina (34.2 %) were significantly enriched on the GAC surface in GAC/H 2 group. Therefore, the coupling of GAC and H 2 provided a novel attempt at anaerobic digestion of hypersaline phenolic wastewater via syntrophic acetate oxidation and hydrogenotrophic methanogenesis pathway. [ABSTRACT FROM AUTHOR]

• Catalytic activity of defective TiO 2 -exposed {0 0 1} facets was higher than TiO 2 P25. • Synergistic factor significantly increased with increasing TiO 2-x dosage. • The contribution of 1O 2 was the most significant in NOR degradation. • NOR degradation achieved by ring opening, defluorination and mineralization. • The GA-ANN model had high accuracy in predicting the NOR degradation efficiency. The wide band gap of titanium dioxide (TiO 2) photocatalyst leads to its narrow optical response, which seriously affects the application of TiO 2. In order to enhance its catalytic efficiency, defective TiO 2 -exposed {0 0 1} facets (TiO 2-x) was prepared and applied to pollutants degradation by combing with the dielectric barrier discharge nonthermal plasma (DBD-NTP), so as to use the ultraviolet light and other active species produced by DBD-NTP. Taking aqueous norfloxacin (NOR) as a model pollutant, the degradation performance of NOR by DBD-NTP and TiO 2-x was evaluated, the synergistic catalytic mechanism and degradation pathways of NOR based on heterogeneous catalysis were proposed. An artificial neural network model based on genetic algorithm optimization (GA-ANN) was constructed to predict the NOR degradation efficiency. The characteristics of TiO 2-x were characterized, and the effects of influencing factors on the NOR degradation efficiency were investigated. The results showed a significant synergistic catalytic effect in NOR degradation by DBD-NTP combined with TiO 2-x. The synergistic catalytic effect substantially increased with increasing TiO 2-x dosage, and the synergistic factor increased by 3.3 times. The reactive agents 1O 2 , OH, O 2 −, h+ and e− played an essential role in NOR degradation, with the contribution of 1O 2 being the most significant. TiO 2-x had good catalytic stability. The degradation pathways of NOR mainly included breakage of the piperazine ring and quinoline ring, decarboxylation, benzene ring defluorination and mineralization. The established GA-ANN model showed high accuracy (mean square error = 0.0016, correlation coefficient = 0.9956) and could be used to predict the degradation efficiency of aqueous NOR. [ABSTRACT FROM AUTHOR]

Microplastic-derived dissolved organic matter (MP-DOM) is ubiquitous in water environment and exhibits photosensitivity. However, little is known about the effects of MP-DOM on the photodegradation of organic micropollutants in natural water. In this study, we investigated the effect of MP-DOM derived from two typical plastics, i.e., polystyrene (PS), and polyethylene (PE), on the photodegradation of a typical organic micropollutants sulfamethoxazole (SMX) in a simulative natural water system. MP-DOM exerted a significant inhibition on the SMX photodegradation, mainly attributed to the direct photolysis inhibition of SMX caused by the inner filter effect and the complexation effect. Despite the enhanced reactive oxygen species (ROS) generation with the increase of their steady-state concentration by 41.1 − 160.7 %, PS-DOM exhibited high oxidation resistance, causing an inhibition on the photodegradation of SMX probably through transferring electrons to the SMX intermediates. This study helps to deepen the understanding of microplastic photochemical behavior in natural water. [Display omitted] • MP-DOM exerted obvious inhibition on sulfamethoxazole (SMX) photodegradation. • Direct photolysis inhibition due to MP-DOM dominated the inhibited SMX degradation. • Direct photolysis was inhibited due to inner filter effect and MP-DOM complexation. • High oxidation resistance of MP-DOM played inhibitory roles on the SMX degradation. [ABSTRACT FROM AUTHOR]

• Plant effects modelled by oxygen and carbon releases from roots for wetlands. • Model calibration and validation by laboratory-scale experiments. • Planted wetlands can tolerate a wide range of COD/N ratio influents. • Nitrogen removal - COD/N ratio curves proposed to evaluate carbon loading status. • Internal organic carbon fuels higher nitrogen removal than external organic carbon. The integrated vertical flow (IVF) constructed wetland consists of two or more chambers with heterogeneous flow patterns and strong aeration capability, possesses favorable remediation performance. The Constructed Wetland Model No.1 (CWM1) embedded in the OpenGeoSys # IPHREEQC was applied to investigate the wetland plant effects on treatment efficiency. Two fundamental functions of the plant roots (i) the radial oxygen loss (ROL) and (ii) exudation of internal organic carbon (IOC), are developed and implemented in the model to simulate the treating processes of planted laboratory-scale IVF wetlands fed by the synthetic wastewater. The good agreement between simulated results and measurements of the planted IVF wetland and the unplanted filters mimicking wetland demonstrates the combined effects of ROL and IOC and the model reliability. In summer the ammonia (NH 4 -N) and total nitrogen (TN) removals are high as above 90% in both IVF wetlands, and in winter they decline significantly to around 55% and 45% in unplanted wetland, contrastively to about 85% and 78% in the planted wetland. The nitrogen removal - COD/N ratio relation curves of IVF wetlands are proposed and obtained by modeling to evaluate organic carbon loading status. Based on the curves, the COD/N ratios of unplanted and planted wetlands are about 3∼7 and 3∼10 gCOD/gN for high TN removal respectively. Planted wetlands can tolerate a wider range of COD/N ratio influents than unplanted ones. The ROL in the unplanted wetland promotes COD and NH 4 -N removal, while may inhibit denitrification under low-temperature conditions. The single addition of IOC enhances the oxygen-consuming and restrains the nitrification under the full loaded COD condition. Summing up all organic carbon releases from substrate and roots as IOC, the quantification of IOC acts on nitrogen treatment was simulated and compared with the external organic carbon (EOC) loading from influent. IOC performs higher efficiency on TN removal than EOC at the same organic loading rates. The results provide the thoughts of the solution for low TN removal in the carbon deficient constructed wetlands. [Display omitted] [ABSTRACT FROM AUTHOR]

• Coupling of GAC and H 2 played a synergistic effect on CH 4 conversion rate of phenol. • Electron transfer activity and hydrogenotrophic methanogenic activity were enhanced. • Coupling of GAC and H 2 enriched Syntrophus , Syntrophorhabdus, and Methanobacterium. • Predominant pathway of SAO-HM in anaerobic digestion of phenol was generated. Anaerobic digestion is a promising biological method for treating phenol-containing wastewater. However, the low methane yield of phenol due to the biological toxicity limits its potential application. This study presents a novel method to enhance the conversion rate of phenol to methane by coupling of granular activated carbon and exogenous hydrogen (GAC/H 2). The cumulative methane production in the GAC/H 2 , H 2 , GAC, and control groups were 408.2 ± 16.2, 336.5 ± 5.7, 287.2 ± 26. 2, and 258.1 ± 8.6 mL‬ CH 4 /g COD, respectively. Compared with the control group, the hydrogenotrophic methanogenic activity and electron transfer activity of GAC/H 2 group were increased by 403.9 and 367.4%, respectively. The results of the 16SrRNA analysis indicated GAC enhanced the relative abundances of Syntrophus and Syntrophorhabdus , and hydrogen promoted the relative abundances of Cryptanaerobacter , Aminicenantes, and Methanobacterium. Therefore, the coupling of GAC and exogenous hydrogen promoted a dominate SAO-HM pathway to convert phenol to methane. [ABSTRACT FROM AUTHOR]

• Ultrasound, ozone and US combined with ozone pretreatments were investigated. • US/ozone pretreatment was effective in the inactivation of indicator bacteria. • Antibiotic resistance genes could not be decreased in absolute concentration. • Pretreatments could reduce the relative abundance of antibiotic resistance genes. • Methane production increased by 10% by 20 min ozone and US/ozone pretreatment. In this study, the effect of ultrasound (US), ozone and US combined with ozone (US/ozone) pretreatments on the fate of enteric indicator bacteria and antibiotic resistance genes (ARGs), and anaerobic digestion (AD) of dairy wastewater was investigated. The pretreatment conditions included US power 200 W, ozone concentration 4.2 mg O 3 /L, and pretreatment time 0–30 min. The results showed that US/ozone pretreatment was effective in the inactivation of enteric indicator bacteria. Total coliforms and enterococci were reduced by 99% and 92% after 30 min US/ozone pretreatment. Pretreatments could not decrease ARGs in absolute concentration, but could decrease ARGs in relative abundance. In the subsequent AD process, methane production increased more than 10% with 20 min ozone or 20 min US/ozone pretreatments. Pretreatment-AD together obviously inhibited the enrichment of ARGs in relative abundance. This study provided a pretreatment way to enhance methane production and to prevent the enrichment of ARGs. [ABSTRACT FROM AUTHOR]

Microplastics are an emerging pollutant of global concern, and fluorescence staining as an efficient method for small-sized microplastic qualification often undergoes the serious interference from external environments. The key steps affecting the accuracy of fluorescent staining and the corresponding quality assurance measures were rarely known. Therefore, this study took the Nile Red/DAPI co-staining method as an example to explore the key factors affecting its accuracy and effective measures to avoid interference. High background microplastic contamination in typical lab waters (up to 1115 MP/L), glass fiber filter membrane and glassware were identified as dominant factors affecting microplastic quantification. The background microplastics in lab waters mainly originated from the process of water production and storage. A simple filtration process removed 99% of the background microplastic in the lab waters. After burning at 500 °C for 1 h, the microplastic contamination in the filter membrane and glassware was completely eliminated. H 2 O 2 pretreatment and exposure time caused erroneous microplastic size assessment, and were suggested to be set at 48 h and 10 ms, respectively. During the extraction process, the residue in beakers reached ~ 20% and > 50% for 5 μm and 20 μm sized microplastics, respectively, greatly contributing to the microplastic loss. The comprehensive modified measures caused microplastic concentrations in the three typical samples detected by Nile Red/DAPI co-staining method to decrease by 65.7 - 92.2% and to approach the micro-Raman results. This study clarified the reasons for interfering with quantitative microplastics by fluorescent staining and the effective measures to avoid interference, which were conducive to improving the accuracy of quantitative methods of microplastics., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Anaerobic conversion rate of phenol to methane was low due to its biological toxicity. In this study, the coupling of granular activated carbon (GAC) and exogenous hydrogen (EH) could enhance greatly methane production of phenol anaerobic digestion, and the metagenomic was firstly used to analyze its potential mechanism. The results indicated that a mass of syntrophic acetate-oxidizing bacteria and hydrogen-utilizing methanogens were enriched on the GAC surface, and SAO-HM pathway has become the dominant pathway. The energy transfer analysis implied that the abundance of adenosine triphosphate (ATP) and nicotinamide adenine dinucleotide (NADH) oxidase increased. Furthermore, direct interspecies electron transfer (DIET) was formed by promoting type IV e-pili between Methanobacterium and Syntrophus, thereby improving the interspecies electron transfer efficiency. The dominant SAO-HM pathway was induced and DIET was formed, which was the internal mechanism of the coupling of GAC and EH to enhance anaerobic biotransformation of phenol., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

As a typical wide band gap photocatalyst, titania (TiO 2 ) cannot use the visible light and has fast recombination rate of photogenerated electron-hole pairs. Simultaneous introduction of erbium ion (Er 3+ ) and graphene oxide (rGO) into TiO 2 might overcome these two drawbacks. In this study, Er 3+ and rGO were co-doped on TiO 2 to synthesize Er 3+ -rGO/TiO 2 photocatalyst through a two-step sol-gel method. Based on the UV-visible diffuse reflectance spectra and photoluminescence spectrum, the introduction of Er 3+ and rGO increased the visible light absorption efficiency and enhanced the migration of photogenerated electron. Pure TiO 2 has almost no photocatalytic activity for arsanilic acid (p-ASA) degradation under visible light irradiation. However, while doping with 2.0 mol% Er 3+ and 10.0 mol% rGO, the p-ASA could be completely degraded within 50 min by the Er 3+ -rGO/TiO 2 photocatalyst under visible light irradiation, and most of produced inorganic arsenic was in situ removed by adsorption from the solution. The reactive oxygen species (ROS) reacting with p-ASA was determined and superoxide radical (O 2 •- ) and singlet oxygen ( 1 O 2 ) were the dominant ROS for the oxidation of p-ASA and arsenite. This work provides an approach of introducing Er 3+ and rGO to enhance the visible light photocatalytic efficiency of TiO 2 ., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Floating photocatalyst is of extensive interest due to easy recovery and efficient light harvest. Support materials largely determine the stability of floating photocatalysts and their synthesis complexity. Thus, finding proper floating supports is very important. Herein, ethylene-vinyl acetate copolymer (EVA) was investigated as a support to prepare floating TiO 2 /EVA using a simple thermal crosslinking procedure. Multiple characterization analyses demonstrated that TiO 2 was anchored onto EVA surface evenly via hydrogen-bond-enhanced physical crosslinking and remained its virgin crystal structure. Photocatalytic experiments showed that the removal efficiency of Rhodamine B (RhB) by floating TiO 2 /EVA increased by 33.8% as compared to suspended particle TiO 2 . The h + and ·O 2 - played dominant roles in TiO 2 /EVA-driven RhB degradation. A 30-day stability test demonstrated that TiO 2 /EVA had a high thermal, pH, and photo- stability. The three-run reuse test proved that TiO 2 /EVA exhibited satisfactory reusability. This study provides a new option for floating photocatalyst synthesis., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Roxarsone (ROX), an organoarsenic feed additive, can be discharged into aquatic environment and photodegraded into more toxic inorganic arsenics. However, the photodegradation behavior of ROX in aquatic environment is still unclear. To better understand ROX photodegradation behavior, the influencing factors, photodegradation mechanism, and process modelling of ROX photodegradation were investigated in this study. The results showed that ROX in the aquatic environment was degraded to inorganic As(III) and As(V) under light irradiation. The degradation efficiency was enhanced by 25% with the increase of light intensity from 300 to 800 μW/cm 2 via indirect photolysis. The photodegradation was temperature dependence, but was only slightly affected by pH. Nitrate ion (NO 3 - ) had an obvious influence, but sulfate, carbonate, and chlorate ions had a negligible effect on ROX degradation. Dissolved organic matter (DOM) in the solution inhibited the photodegradation. ROX photodegradation was mainly mediated by reactive oxygen species (in the form of single oxygen 1 O 2 ) generated through ROX self-sensitization under irradiation. Based on the data of factors affecting ROX photodegradation, ROX photodegradation model was built and trained by an artificial neural network (ANN), and the predicted degradation rate was in good agreement with the real values with a root mean square error of 1.008. This study improved the understanding of ROX photodegradation behavior and provided a basis for controlling the pollution from ROX photodegradation., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Aromatic organoarsenicals are widely used in animal feeding operations and cause arsenic contamination on livestock wastewater and manure, thereby raising the risk of surface water pollution. Biological wastewater treatment processes are often used for livestock wastewater treatment. Organoarsenic removal and biotransformation under aerobic and anaerobic conditions, and the associated impacts have received extensive attention due to the potential threat to water security. The removal efficiency and biotransformation of organoarsenicals in biological treatment processes are reviewed. The underlying mechanisms are discussed in terms of functional microorganisms and genes. The impacts associated with organoarsenicals and their degradation products on microbial activity and performance of bioreactors are also documented. Based on the current research advancement, knowledge gaps and potential research in this field are discussed. Overall, this work delivers a comprehensive understanding on organoarsenic behaviors in biological wastewater treatment processes, and provides valuable information on the control of arsenic contamination from the degradation of organoarsenicals in biological wastewater treatment processes., (Copyright © 2020 Elsevier B.V. All rights reserved.)

3,5-Dinitrobenzamide has been widely used as a feed additive to control coccidiosis in poultry, and part of the added 3,5-dinitrobenzamide is excreted into wastewater and surface water. The removal of 3,5-dinitrobenzamide from wastewater and surface water has not been reported in previous studies. Highly reactive hydroxyl radicals from UV/hydrogen peroxide (H 2 O 2 ) and UV/titanium dioxide (TiO 2 ) advanced oxidation processes (AOPs) can decompose organic contaminants efficiently. In this study, the decomposition of 3,5-dinitrobenzamide in aqueous solution during UV/H 2 O 2 and UV/TiO 2 oxidation processes was investigated. The decomposition of 3,5-dinitrobenzamide fits well with a fluence-based pseudo-first-order kinetics model. The decomposition in both two oxidation processes was affected by solution pH, and was inhibited under alkaline conditions. Inorganic anions such as NO 3 - , Cl - , SO 4 2- , HCO 3 - , and CO 3 2- inhibited the degradation of 3,5-dinitrobenzamide during the UV/H 2 O 2 and UV/TiO 2 oxidation processes. After complete decomposition in both oxidation processes, approximately 50% of 3,5-dinitrobenzamide was decomposed into organic intermediates, and the rest was mineralized to CO 2 , H 2 O, and other inorganic anions. Ions such as NH 4 + , NO 3 - , and NO 2 - were released into aqueous solution during the degradation. The primary decomposition products of 3,5-dinitrobenzamide were identified using time-of-flight mass spectrometry (LCMS-IT-TOF). Based on these products and ions release, a possible decomposition pathway of 3,5-dinitrobenzamide in both UV/H 2 O 2 and UV/TiO 2 processes was proposed.

The advent of methicillin-resistant Staphylococcus aureus (MRSA) and the frequent and excessive abuse of ventilators have made MRSA pneumonia an inordinate threat to human health. Appropriate antibacterial therapies are crucial, including the use of lysostaphin as an alternative to antibiotics. To explore the potential use of lysostaphin as a therapeutic agent for MRSA pneumonia, mice were intranasally infected with MRSA and then treated with recombinant lysostaphin (rLys; 45 mg/kg in the high-dose group and 1 mg/kg in the low-dose group) (0.33 mg/mL, 15 mg/mL), vancomycin (120 mg/kg) (40 mg/mL), or phosphate-buffered saline (PBS, negative control) 4 h after infection. Therapeutic efficacy was assessed by mouse survival, lung histopathology, bacterial density in the lungs, bodyweight, lung weight, temperature, white blood cells counts, lymphocytes counts, granulocytes counts, and monocytes counts. The mice treated with rLys showed lower mortality, less lung parenchymal damage, and lower bacterial density at metastatic tissue sites than mice treated with PBS or vancomycin. The overall mortality was 100%, 60%, 40%, and 60% for the control, vancomycin, high-dose rLys, and low-dose rLys groups, respectively. These findings indicate that, as a therapeutic agent for MRSA pneumonia, lysostaphin exerts profound protective effects in mice against the morbidity and mortality associated with S. aureus pneumonia.