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Microplastics (MPs) are increasingly recognized as contaminants present in various environments and are widely acknowledged as potential hazards to the mammalian immune system. In our study of chimeric antigen receptor T cell (CAR-T) therapy, we observed the presence of MP in CAR-T cell products for the first time. It is worth exploring whether MP could enter CAR-T cells and how they might affect CAR-T cells' functionality. Therefore, we analyzed how MP affected CD19 and BCMA-CAR-T cells. Based on flow cytometry, ELISA, and cytotoxicity analysis of in vitro and in vivo experiments, MP suppressed the activity of CAR-T cells. Subsequent investigation revealed that the exposure of CAR-T cells to varying concentrations of MP resulted in a notable increase in apoptosis, ferroptosis, and exhaustion levels. Furthermore, the hyperactivation of the mTOR signaling pathway in MP-treated CAR-T cells was verified. The partial restoration of CAR-T cell function in MP was achieved by inhibiting the mTOR pathway. MP present a threat to CAR-T cell function due to their role in inducing CAR-T cell apoptosis, ferroptosis, and T-cell exhaustion through the hyperactivation of mTOR signaling pathways., Competing Interests: Declaration of Competing Interest Our authors claim no known personal relation or competing financial interests affecting this work., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Catalytic ozone (O 3 ) decomposition is a promising technology for curbing indoor O 3 pollution, whereas its application is limited by the stability and moisture resistance of heterogeneous catalysts. Ag-Hollandite is a capable solution, but its facile synthesis still lacks systematic investigation. In this study, Ag-Hollandite catalysts were prepared using AgMnO 4 as the precursor by reflux (AMO-Re), hydrothermal (AMO-HT), and homogeneous (AMO-HR) methods, respectively. The as-prepared samples showed excellent stability under moisture conditions, with the optimal one maintaining an O 3 conversion rate of 99.19 % after 100 h. In the characterization results, Ramsdellite (R-MnO 2 ) was identified as an intermediate species in the synthesis. AMO-HR exhibits higher activity due to enhanced active site exposure and weakened adsorption towards *OO species, while reduced surface hydroxyl content was a crucial factor for moisture resistance. This study aims to contribute insights for preparing catalysts by a facile method., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The composition and metabolites of the gut microbiota can be altered by environmental pollutants. However, the effect of co-exposure to multiple pollutants on the human gut microbiota has not been sufficiently studied. In this study, gut microorganisms and their metabolites were compared between 33 children from Guiyu, an e-waste dismantling and recycling area, and 34 children from Haojiang, a healthy environment. The exposure level was assessed by estimating the daily intake (EDI) of polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs), 6PPD-quinone (6PPDQ), and metal(loid)s in kindergarten dust. Significant correlations were found between the EDIs of 6PPDQ, BDE28, PCB52, Ni, Cu, and the composition of gut microbiota and specific metabolites. The Bayesian kernel machine regression model showed negative correlations between the EDIs of five pollutants (6PPDQ, BDE28, PCB52, Ni, and Cu) and the composition of gut microbiota. The EDIs of these five pollutants were positively correlated with the levels of the metabolite 2,4-diaminobutyric acid, while negatively correlated with the levels of d-erythro-sphingosine and d-threitol. Our study suggests that exposure to 6PPDQ, BDE28, PCB52, Ni, and Cu in kindergarten dust is associated with alterations in the composition and metabolites of the gut microbiota. These alterations may be associated with children's health., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

We provide transect profiles of 137 Cs and 90 Sr along 146.5°E, 136°E and 21°N in the subtropical western North Pacific (WNP) during May 2018. Exploiting the constant global fallout 137 Cs/ 90 Sr ratio, we separated Fukushima-derived 137 Cs ( 137 Cs F ) from background 137 Cs. At most stations, 137 Cs F exhibited only one subsurface peak at 300 m depth, corresponding to subtropical mode water (STMW); however, at 25-28°N along 146.5°E and 25-26°N along 136°E, 137 Cs F exhibited two subsurface peaks, with another peak occurring at 500 m depth, corresponding to lighter central mode water (L-CMW). Temporal changes in 137 Cs F vertical profiles showed that 137 Cs F entrained by STMW has recirculated within the western subtropical gyre, while 137 Cs F entrained by L-CMW has turned southwestward and arrived the western basin in 2018. In the Luzon Strait, the entrance to the South China Sea (SCS), subsurface 137 Cs increased since 2013 and peaked in approximately 2018. The estimated amount of 137 Cs F entering the SCS during 2013-2019 was 0.33 ± 0.10 PBq, equivalent to 1.7-2.2% of total leakage of 137 Cs F into the ocean. These results enhance our understanding of the protracted spread and fate of 137 Cs F in the subtropical WNP., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Vanadium dioxide (VO 2 ) has been used in a variety of products due to its outstanding phase transition properties. However, as potential heavy metal contaminants, the environmental hazards and risks of VO 2 should be systematically investigated. Biological nitrogen fixation is one of the most dominant processes in biogeochemical cycle, which is associated with nitrogen-fixing bacteria. In this study, we reported the environmental bio-effects of VO 2 micro/nanoparticles on the nitrogen-fixing bacterium Azotobacter vinelandii. VO 2 at 10 and 30 mg/L caused severe hazards to A. vinelandii, such as cell apoptosis, oxidative damage, physical damage, genotoxicity, and the loss of nitrogen fixation activity. The up-regulated differentially expressed genes of A. vinelandii were related to stress response, and the down-regulated genes were mainly related to energy metabolism. Surprisingly, VO 2 of 10 mg/L decreased the nif gene expression but elevated the vnf gene expression, which enhanced the ability of A. vinelandii to reduce acetylene in anaerobic environment. In addition, under tested conditions, VO 2 nanoparticles exhibited insignificantly higher toxicity than VO 2 microparticles., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Catalytic ozone (O 3 ) decomposition at ambient temperature is an efficient method to mitigate O 3 pollution. However, practical application is hindered by the poor water resistance of catalysts. Herein, Ag-Hollandite (Ag-HMO) with varying Ag + content was synthesized. Catalysts with more Ag + exhibited improved efficiency and water-resistance, with the optimal one maintaining 98% O 3 conversion at 70% relative humidity (RH) within 8 h. Physicochemical characterizations revealed that Ag + had entered the tunnel of OMS-2, facilitating oxygen species removal. Notably, enhanced H 2 O desorption and the complete inhibition of chemisorbed water formation on Ag-HMO were the primary reasons for its high-efficiency O 3 conversion across a wide humidity range. The underlying mechanism arises from the charge redistribution induced by the Ag-O interaction within the tunnel, which reduces acidity and modulates hydrophilicity. This study aims to contribute insights for designing catalysts with higher water-resistance., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Recently, peracetic acid (PAA) based Fenton (-like) processes have received much attention in water treatment. However, these processes are limited by the sluggish Fe(III)/Fe(II) redox circulation efficiency. In this study, L-cysteine (L-Cys), an environmentally friendly electron donor, was applied to enhance the Fe 3 O 4 /PAA process for the sulfamethoxazole (SMX) abatement. Surprisingly, the L-Cys incorporation was found not only to enhance the SMX degradation rate constant by 3.2 times but also to switch the Fe(IV) dominated nonradical pathway into the • OH dominated radical pathway. Experiment and theoretical calculation result elucidated -NH 2 , -SH, and -COOH of L-Cys can increase Fe solubilization by binding to the Fe sites of Fe 3 O 4 , while -SH of L-Cys can promote the reduction of bounded/dissolved Fe(III). Similar SMX conversion pathways driven by the Fe 3 O 4 /PAA process with or without L-Cys were revealed. Excessive L-Cys or PAA, high pH and the coexisting HCO 3 - /H 2 PO 4 - exhibit inhibitory effects on SMX degradation, while Cl - and humic acid barely affect the SMX removal. This work advances the knowledge of the enhanced mechanism insights of L-Cys toward heterogeneous Fenton (-like) processes and provides experimental data for the efficient treatment of sulfonamide antibiotics in the water treatment., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Long-term ingestion or exposure to food contaminated with per- and polyfluoroalkyl substances (PFASs) may cause potential harm to human health. Due to the low contents of PFASs in complex food matrices, it is of great significance to develop adsorbents with excellent properties to enrich PFASs before analysis. Herein, calix[4]arene (CX4) was used as building block to prepare ordered crystalline covalent organic frameworks (COFs). The perfect combination of the host-guest recognition ability of CX4 and the porosity of COFs makes the CX4-COFs selective and high adsorption capacity for linear molecular PFASs (261-1055 mg/g). The adsorption behavior and mechanism were verified by isotherm adsorption experiments and simulation calculations. The CX4-COFs were then used as adsorbents for membrane solid-phase extraction (M-SPE), combined with ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) to determine PFASs in food. The method has low detection limits (0.11-0.28 ng/kg) and good precision (1.3%-9.8%), and has been successfully applied to the simultaneous enrichment and determination of six PFASs in fish, shrimp and shellfish. Satisfactory recoveries (79.9%-118%) were obtained. This study provides a new strategy for preparing CX4-COFs containing macrocyclic molecules with different morphologies and expands the application of COFs as attractive enrichment media for sample pretreatment., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Metal-organic frameworks (MOFs) are rapidly developed materials with fantastic properties and wide applications. The increasing studies highlighted the potential threats of MOF materials to the environment. Comparing to the limited species of metal elements, the organic ligands have much higher diversity, but the influence of organic ligands on the environmental impacts of MOFs has not been revealed. Herein, we synthesized three Cu-MOFs with different organic ligands, namely Cu-BDC (1,4-terephthalic acid), Cu-IM (imidazole) and Cu-TATB (2,4,6-tris(4-carboxyphenyl)- 1,3,5-triazine), and evaluated their environmental toxicity to the nitrogen-fixing bacterium Azotobacter vinelandii. Cu-BDC inhibited the bacterial growth at lower concentrations than Cu-IM and Cu-TATB. The transcriptomes suggested the changes of membrane components by Cu-MOFs, consistent with the membrane leakage and cell wall damages. Cu-MOFs inhibited the nitrogen fixation activity through energy metabolism disturbance according to Gene Ontology functional annotation of ATP binding, Ca 2+ Mg 2+ -ATPase activity and ATP content. Only Cu-IM lowered the nitrogen fixation related nif genes, and affected the ribosome, purine metabolism and oxidative phosphorylation pathways. Otherwise, Cu-BDC and Cu-TATB mainly affected the flagellar assemblies and bacterial chemotaxis pathways. Our results collectively indicated that organic ligands regulated the environmental toxicity of MOFs through different metabolism pathways., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Staphylococcal enterotoxin C (SEC) is an enterotoxin produced by Staphylococcus aureus, which can cause intestinal diseases. Therefore, it is of great significance to develop a sensitive detection method for SEC to ensure food safety and prevent foodborne diseases in humans. A field-effect transistor (FET) based on high-purity carbon nanotubes (CNTs) was used as a transducer, and a nucleic acid aptamer with high affinity was used for recognition to capture the target. The results indicated that the biosensor achieved an ultra-low theoretical detection limit of 1.25 fg/mL in PBS, and its good specificity was verified by detecting target analogs. Three typical food homogenates were used as the solution to be measured to verify that the biosensor had a swift response time (within 5 min after sample addition). An additional study with a more significant basa fish sample response also showed excellent sensitivity (theoretical detection limit of 8.15 fg/mL) and a stable detection ratio. In summary, this CNT-FET biosensor enabled the label-free, ultra-sensitive, and fast detection of SEC in complex samples. The FET biosensors could be further used as a universal biosensor platform for the ultrasensitive detection of multiple biological toxic pollutants, thus considerably stopping the spread of harmful substances., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Electrochemical reduction of NO to NH 3 (NORR) is an attractive approach to mildly realize NO removal and valuable NH 3 production. The electrolyte, as function as the NO absorbent, is crucial to apply electrochemical technology in practical de-NO engineering. In this paper, the ferrous chelate acted as the electrolyte for effective NO absorption in NORR based on the Brown-ring reaction. The rGO and Au/rGO catalysts served as cathodes to realize ferrous regeneration for continuous NO reduction. The results revealed that ferric chelate could be fully reduced at lower onset potential on rGO electrode. The Au/rGO catalyst exhibited excellent average yield and selectivity for NH 3 at - 0.1 V and pH = 6.32, (14.6 μmol* h -1 * cm -2 and 65.2%, respectively). The Faradaic Efficiency of NH 3 could reach 98.3% at pH = 1.0. This work provides a valuable reference for effective NO adsorption and sustainable NO-to-NH 3 conversion., (Copyright © 2022. Published by Elsevier B.V.)

A new method was developed to scrub NO x compounds in flue gases during the integrated technology of WFGD associated with ozone oxidation, among which polyethylene glycol (PEG) was utilized initially as an additive to facilitate the absorption of NO 2 by sulfite solution. Notably, absorption was significantly facilitated with adding PEG into absorbent. Compared to absorption by sulfite solution alone, NO 2 removal efficiency with PEG addition increased from 58.75% to 89.17%. Furthermore, the favorable role of PEG was considered to be ascribed to the its improvement on the rate-determining step among absorption process ── mass transfer of NO 2 into the liquid phase. A potential chemical transformation pathway between NO 2 , SO 3 2- and PEG was proposed, and based on the hydrogen bonding between the various compounds. Additionally, a kinetic model was established based on various operating parameters that included adsorbent pH, ionic strength of S species, temperature, flow rate, and inlet SO 2 concentration. This model provides theoretical support for practical engineering., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Sulfamethoxazole (SMX) is highly persistent and difficult to remove, making it urgent to find an efficient method for alleviating the enormous environmental pressure of SMX. In this study, sulfide-modified nanoscale zero-valent iron on carbon nanotubes (S-nZVI@CNTs) was prepared to activate peroxydisulfate (PDS) for the degradation of SMX. The results showed that SMX was completely removed within 40 min (k obs =0.1058 min -1 ) in the S-nZVI@CNTs/PDS system. By analyzing quenching experiments and electron paramagnetic resonance (EPR), singlet oxygen ( 1 O 2 ) was the main active species of the S-nZVI@CNTs/PDS system. 1 O 2 might be mediated by the abundant carbonyl groups (CO) on carbon nanotubes through spectroscopic analyses. In addition, sulfur doping transitioned the activation pathway to a nonradical pathway. Spectroscopic analyses and electrochemical experiments confirmed that the formation of CNTs-PDS complexes and S-nZVI could promote electron transfer on the catalyst surface. Furthermore, the main degradation intermediates of SMX were identified, and five possible transformation pathways were proposed. The S-nZVI@CNTs/PDS system possessed advantages including high anti-interference (Cl - , NO 3- , HA), a strong applicability, recyclability and a low PDS consumption, offering new insight into the degradation of antibiotic wastewater., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Uranium mill tailings (UMTs) are one critical source of environmental U pollution. Leaching test has been extensively used to reveal U release capacity and mechanism from UMTs, while little attention has been paid to the effects of re-adsorption process on U release. In this study, the role of U re-adsorption behaviors during leaching test with UMTs was comprehensively investigated. Through paired data on mineralogical composition and aqueous U speciation, the influence of environmentally relevant factors on U re-absorption capacity and mechanism on UMTs with different particle sizes was revealed. Significant amounts of U re-adsorption were observed and primarily attributed to the adsorption on chlorite, albite and muscovite as well as combined reduction-sequestration by muscovite. Uranium re-adsorption predominantly occurred via inner-sphere complexation and surface precipitation depending on leachant pH. Coexisting sulfate or phosphate could further enhance U re-adsorption. The enhanced re-adsorption from sulfate occurred when inner-sphere complexation governed the re-adsorption process. These findings suggest that the environmental hazards and ecological risks of the U containing (waste) solids might have been underestimated due to the ignorance of the re-adsorption process, since the re-adsorbed U could be easily re-mobilized. The insights from this study are also helpful in developing effective in-situ remediation strategies., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Uranium (U) geochemistry and its isotopic compositions of reservoir sediments in U mine area were poorly understood. Herein, U and Th isotopic compositions were employed to investigate source apportionment and geochemical behavior of U in 41 reservoir sediments from a U mining area, Guangdong, China. The remarkably high contents of both total U (207.3-1117.7 mg/kg) and acid-leachable U (90.3-638.5 mg/kg) in the sediments exhibit a severe U contamination and mobilization-release risk. The U/Th activity ratios (ARs) indicate that all sediments have been contaminated apparently by U as a result of discharge of U containing wastewater, especially uranium mill tailings (UMT) leachate, while the variations of U/Th ARs are dominated by U geochemical behaviors (mainly redox process and adsorption). The U isotopic compositions (δ 238 U) showed a large variance through the sediment profile, varying from - 0.62 to - 0.04‰. The relation between δ 238 U and acid-leachable U fraction demonstrates that the U isotopic fractionation in sediments can be controlled by bedrock weathering (natural activity), UMT leachate (anthropogenic activity) and subsequent biogeochemical processes. The findings suggest that U-Th isotopes are a powerful tool to better understand U geochemical processes and enrichment mechanism in sediments that were affected by combined sources and driving forces., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Microbial resistance to antibiotics is a growing challenge to human health. Recent evidence has indicated that antibiotic resistance can be co-selected for by exposure to heavy metals in agricultural soils. It remains unknown if this is a concern in other environments contaminated by metals. We here investigated soil microbial activities, composition and tolerance to heavy metals and antibiotics in a mining soil survey. We found that microbial respiration, growth, and biomass were affected by available metal concentrations. Most of the variation in microbial PLFA composition was explained by differences in heavy metal and pH. Additionally, pollution-induced bacterial community tolerance to toxicants including Cu, Pb, Zn, tetracycline and vancomycin was determined. Although only bacterial tolerance to Pb increased with higher levels of metals, the links between bacterial metal tolerance and soil metal concentrations were clear when considered together with previously published reports, suggesting that bacterial metal tolerance were universally elevated in the surveyed soils. The induced levels of heavy metal tolerance coincided with elevated levels of tolerance to vancomycin, but not to tetracycline. Our study showed that heavy metals can co-select for resistance to clinically important antibiotics also in ecosystems without manure input or antibiotic pollution., (Copyright © 2021. Published by Elsevier B.V.)

The impacts of metal(loids) on soil microbial communities are research focuses to understand nutrient cycling in heavy metal-contaminated environments. However, how antimony (Sb) and arsenic (As) contaminations synergistically affect microbially-driven ecological processes in the rhizosphere of plants is poorly understood. Here we examined the synergistic effects of Sb and As contaminations on bacterial, archaeal and fungal communities in the rhizosphere of a pioneer plant (Miscanthus sinensis) by focusing on soil carbon and nitrogen cycle. High contamination (HC) soils showed significantly lower levels of soil enzymatic activities, carbon mineralization and nitrification potential than low contamination (LC) environments. Multivariate analysis indicated that Sb and As fractions, pH and available phosphorus (AP) were the main factors affecting the structure and assembly of microbial communities, while Sb and As contaminations reduced the microbial alpha-diversity and interspecific interactions. Random forest analysis showed that microbial keystone taxa provided better predictions for soil carbon mineralization and nitrification under Sb and As contaminations. Partial least squares path modeling indicated that Sb and As contaminations could reduce the carbon mineralization and nitrification by influencing the microbial biomass, alpha-diversity and soil enzyme activities. This study enhances our understanding of microbial carbon and nitrogen cycling affected by Sb and As contaminations., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Cadmium (Cd) is a toxic heavy metal pollutant. Various industrial activities, especially metal smelting, are the main sources of Cd pollution. Cd isotopes have exhibited the ability to be excellent source tracers and can be used to assess the pollution contributions from different sources. Herein, in a typical lead-zinc smelter, Shaoguan, China, significant Cd isotopic fractionation was found during the high temperature smelting process and followed a Rayleigh distillation model. The heavier Cd isotopes were concentrated in the slag, while the lighter Cd isotopes were concentrated in the dust. In the downstream sediment profile of the smelter, sediments have extremely high Cd concentrations that far exceed the Chinese background sediment, indicating severe pollution levels. The ε 114/110 Cd of the sediment core, ranged from - 0.62 ± 0.5-1.73 ± 0.5, are found between slag (ε 114/110 Cd=10.42) and dust (ε 114/110 Cd=-5.68). The binary mixture model suggests that 88-93% of the Cd in sediment profile was derived from the slag, and 7-12% from the deposition of dust. The findings demonstrate the great potential to apply Cd isotopes as a new geochemical tool to distinguish anthropogenic sources and quantify the contribution from various sources in the environment., (Copyright © 2021 Elsevier B.V. All rights reserved.)

In this study, a novel double redox (DR) method was developed to synthesize highly active CuO-CeO 2 (CuCe-DR) catalyst for catalytic oxidative decomposition of toluene. Compare with CuCe-C catalyst prepared by co-precipitation method, CuCe-DR catalyst exhibits a higher Ce 3+ ion and incorporated Cu 2+ ion concentration, and has a stronger Cu-Ce interaction. Ce 3+ and incorporated Cu 2+ ions can induce the formation of oxygen vacancies, and thus increasing the amount of surface chemisorbed oxygen on CuCe-DR catalyst. The strong Cu-Ce interaction can promote the electron transfer between CuO and CeO 2 , which improves the redox properties of CuCe-DR catalyst. Although CuCe-DR catalyst has a lower toluene adsorption capacity, CuCe-DR exhibits much higher toluene oxidation performance than CuCe-C at the temperature below 300 °C. Moreover, CuCe-DR shows higher stability than CuCe-C during 100 h long-term test due to its high oxygen mobility which inhibits coking. Finally, the possible reaction pathways and promotional mechanism on CuCe-DR in toluene oxidation are proposed. We expect this study to shed more light on the nature of the surface active site(s) of CuCe catalyst for VOCs oxidation and the development of novel redox preparation method for the synthesis highly-active catalysts., (Copyright © 2020. Published by Elsevier B.V.)

Spent carbon cathode (SCC), a hazardous solid waste discharged from the aluminum electrolysis industry, has a serious environmental pollution risk. This study aims to explore an environmental friendly process for dissociating toxic substances and recovering valuable components from SCC. Parameters of molten salt-assisted roasting and water leaching were optimized. A possible dissociation mechanism of toxic substances was proposed. Results showed that 99.12% of cyanide was decomposed and 96.63% of fluoride was leached under optimal conditions. The recovery route of fluoride was designed according to the solution equilibrium chemical calculation and the difference in solubility and particle size between the recovered products. Exhaust gas with a high concentration of CO and CO 2 was used for the carbonation of the leaching solution to recover cryolite. Effects of reaction conditions on precipitation mass and phase composition of recovered cryolite were investigated in detail. Characterization results indicated that the crystallinity and particle size of cryolite recovered under optimal conditions were extremely similar to those of commercial products. Finally, NaF and Na 2 CO 3 were separated and recovered via evaporative crystallization combined with selective filtration. This proposed process with circular economy and green chemistry characteristics is expected to recover valuable components while minimizing environmental hazards of SCC., (Copyright © 2020 Elsevier B.V. All rights reserved.)

To achieve high NO oxidation efficiency, excessive O 3 must be used, which would lead to the high cost and escape of ozone. Herein, we adopted low cost and environmental-friendly TiO 2 as the catalyst of low concentration O 3 and H 2 O 2 system for high-efficiency NO x oxidation. The Ti sites on TiO 2 were the deprotonation sites of H 2 O 2 and H 2 O into Ti-OOH and Ti-OH species, respectively. We found that the surface of rutile phase TiO 2 had a low concentration Ti-OOH component but a large amount of Ti-OH after contacting with H 2 O 2 solution, thus lots of ·OH and a few O 2 - radicals formed with introducing O 3 molecules. H 2 O 2 solution induced the formation of a large amount of Ti-OOH and Ti-OH species on the anatase phase TiO 2 surface, thus lots of O 2 - generated in the O 3 /H 2 O 2 system. O 2 - and OH radicals could efficiently oxidize NO, in which O 2 - radicals could oxidize NO to NO 3 - in one step with high selectively. Therefore, anatase TiO 2 had better performance in NO x oxidation than rutile phase TiO 2 . The effect of temperature and SO 2 concentration on NO oxidation was also investigated, the results showed that TiO 2 -A/O 3 /H 2 O 2 system promoted NO oxidation at a low temperature and a low concentration of SO 2 ., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Biochar as an environmental-friendly and low-cost catalyst has gained increasing attention in the catalytic degradation of organic pollutants. However, the roles of endogenous mineral constituents in biochar in the catalytic degradation are still unclear. In this study, the mineral-rich biochar produced from sewage sludge at 400 °C (SS400) and 700 °C (SS700) and their corresponding demineralized biochar (DSS400 and DSS700) were used to be the persulfate (PS) activator for phenol degradation. Results showed that the mineral-rich biochar + PS system had negligible phenol degradation (≤12.6 %), whereas distinct degradation of phenol were obtained in the demineralized biochar + PS system where DSS400 + PS and DSS700 + PS exhibited 36.3 % and 57.8 % degradation, respectively. Different minerals in mineral-rich biochar exhibited varying functions on phenol degradation. Mg and K in biochar had less effect on the phenol degradation, while Fe-containing minerals favored the phenol degradation. However, Ca-containing minerals more greatly reduced the formation of hydroxyl radical, resulting in more inhibited degradation of phenol. Thus, the overall degradation of phenol was reduced by the mineral-rich biochar. The findings indicated that the inherent minerals in biochar were not favorable for the phenol degradation, which guides us the application of biochar containing different minerals in the remediation of organic pollutants., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Novel Fe-doped CePO 4 (Fe x Ce 1-x ) catalyst was firstly successfully synthesized via a simple co-precipitation method and demonstrated excellent NH 3 -SCR performance in comparison with FePO 4 and CePO 4 . In order to study the promoting effects of Fe 3+ ion on the NH 3 -SCR activity of CePO 4 catalyst, various characterizations were conducted. It was found that NH 3 capacity of Fe x Ce 1-x catalyst was controlled by P sites and depended on their specific surface area. Interestingly, Fe species in Fe x Ce 1-x were not a Lewis acid site for NH 3 adsorption, but it could promote the activation of NH 3 . More importantly, Fe 3+ doping could induce the redox equilibrium of Fe 3+ + Ce 3+ ⇆ Fe 2+ + Ce 4+ , which significantly improved redox properties of CePO 4 catalyst. Accordingly, improved catalytic activity of Fe x Ce 1-x catalysts could be attributed to the collective effects of the higher surface area, better redox properties and easily activated NH 3 . Among them, superior redox property of Fe x Ce 1-x catalysts was the main reason boosting their high catalytic activity. Finally, the reaction process analyzed by in situ DRIFT proposed that the NH 3 -SCR reaction over CePO 4 and Fe x Ce 1-x occurred mainly via Eley-Rideal mechanism. We anticipated this work could promote the development of novel NH 3 -SCR catalyst., (Copyright © 2019. Published by Elsevier B.V.)

Soil washing is a rapid and efficient remediation technique for soil contaminated by heavy metals. In this study, Cd, Pb, and Zn were removed from contaminated soil by ethylenediamine tetra (methylene phosphonic acid) (EDTMP) and polyacrylic acid (PAA). We then investigated the effect of varying the concentration, pH and duration of the washing processes. Single-factor experiments suggest that the PAA washing process may be dominated by electrostatic adsorption, and is suitable for remediation under weak acid and neutral conditions. Meanwhile, EDTMP remediation might be dominated by chelation, which is favorable in strong acid and alkaline environments. In a quadratic saturation D-optimization design (QSDD), we optimized the washing parameters and further explored the washing mechanism including primary factor, principal effect, interaction effect, and the optimal washing conditions, with simultaneously changing multiple influencing factors. The optimum efficiencies of Cd, Pb, and Zn removal were 92.74%, 96.14%, and 50.76% respectively in EDTMP remediation, and 84.62, 79.24, and 41.66% respectively in PAA remediation. The washing processes effectively reduced the availability of Cd, Pb, and Zn in contaminated soil, without noticeably affecting soil chemical properties. Therefore, the washing incurred little ecological risk. EDTMP and PAA are suitable remediation agents of soil contaminated by heavy metals., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Soil washing, which is used to remove heavy metals from soil, is dependent on suitable washing agents. However, there is still a lack of economical, environmentally friendly washing agents with high removal efficiency. In this study, three washing agents, carboxyalkylthiosuccinic acid (CETSA), copolymer of maleic and acrylic acid (MA/AA) and ethylenediamine tetra acetic acid (EDTA), were used to remove heavy metals from contaminated soil. The influence of washing solution concentration, pH and washing time on heavy metals removal was also investigated. The cadmium (Cd), lead (Pb), and zinc (Zn) removal efficiencies increased as washing solution concentrations increased from 0 to 60 g L -1 , while they declined as pH increased from 3 to 8. Despite fluctuations between 90 and 120 min, heavy metal removal efficiencies increased continuously from 10 to 90 min. The three agents also effectively reduced the potential risks of Cd, Pb, and Zn in contaminated soil, but only CETSA and MA/AA produced no significant changes in chemical properties. Fourier transform infrared spectroscopy revealed that the hydroxyl, carboxyl, carbonyl, methoxyl, and sulfur groups were related to the heavy metal ions from the soil colloids. Thus, CETSA and MA/AA were suitable washing agents for remediation of heavy metals contaminated soil., (Copyright © 2018 Elsevier B.V. All rights reserved.)

A novel selective denitrification process, referred as O3-ethanol oxidation method, was developed by injecting O3 and ethanol mixtures into the simulated flue gas duct. The organic radicals, generated through the ethanol oxidation by O3, can oxidize NO into NO2, and finally into important industrial raw, namely, nitrate organics or aqueous nitrate acids. The residual ethanol in the tail can be recycled. The CO3(2-), HCO3(-) and SO2 in the flue gas hardly exhibit any effect on the NOX removal. Compared to the conventional O3 oxidation method, the present method shows higher selective oxidation of NO, higher NO(X) removal and less O3 consumption as well as proves lower initial investment and operating costs with more compact equipment., (Copyright © 2016 Elsevier B.V. All rights reserved.)

In this paper, an enhanced visible-light photocatalytic oxidation (PCO) of NO (∼ 400 ppm) in the presence of the graphitic carbon nitride (g-C3N4) treated by the alkaline hydrothermal treatment is evaluated. Various g-C3N4 samples were treated in different concentrations of NaOH solutions and the sample treated in 0.12 mol L(-1) of NaOH solution possesses the largest BET specific surface area as well as the optimal ability of the PCO of NO. UV-vis diffuse reflection spectra (DRS) and photoluminescence (PL) spectra were also conducted, and the highly improved photocatalytic performance is ascribed to the large specific surface area and high pore volume, which provides more adsorption and active sites, the wide visible-light adsorption edge and the narrow band gap, which is favorable for visible-light activation, as well as the decreased recombination rate of photo-generated electrons and holes, which could contribute to the production of active species. Fluorescence spectra and a trapping experiment were conducted to further the mechanism analysis of the PCO of NO, illustrating that superoxide radicals (O2(-)) play the dominant role among active species in the PCO of NO., (Copyright © 2015 Elsevier B.V. All rights reserved.)

A novel, simple, reproducible and low-cost strategy is introduced for the size- and shape-controlled synthesis of iron-aluminum mixed oxide nanoparticles (NIAO(x/y)). The as-synthesized NIAO(x/y) catalyze decomposition of H2O2 yielding highly reactive hydroxyl radicals (OH) for NOX and SO2 removal. 100% SO2 removal is achieved. NIAO(x/y) with Fe/Al molar ratio of 7/3 (NIAO(7/3)) shows the highest NOX removal of nearly 80% at >170°C, whereas much lower NOX removal (<63%) is obtained for NIAO(3/7). The melting of aluminum oxides in NIAO(7/3) promotes the formation of lamellar products, thus improving the specific surface areas and mesoporous distribution, benefiting the production of OH radicals. Furthermore, the NIAO(7/3) leads to the minor increase of points of zero charges (PZC), apparent enhancement of FeOH content and high oxidizing ability of Fe(III), further improving the production of OH radicals. However, the NIAO(3/7) results in the formation of aluminum surface-enriched spherical particles, thus decreasing the surface atomic ratio of iron oxides, decreasing OH radical production. More importantly, the generation of FeOAl causes the decline of active sites. Finally, the catalytic decomposition of H2O2 on NIAO(x/y) is proposed. And the well catalytic stability of NIAO(7/3) is obtained for evaluation of 30 h., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Mn modified the commercial magnesite powder prepared by wet impregnation method has been shown to be effective for gas-phase elemental mercury (Hg(0)) removal at low temperatures. The prepared samples are characterized in detail across multiform techniques: XRF, BET, SEM-EDX, XRD, H2-TPR, and XPS, and all the results show that the amorphous MnO2 impregnated on magnesite powder improves the removal efficiency of Hg(0). Through further analysis by TG and in situ FTIR, the reasonable removal mechanism is also speculated. The results indicate that chemisorbed oxygen is an important reactant in the heterogeneous reaction, and gas-phase Hg(0) is adsorbed and then oxidized to solid MnHgO3 on the surface of the adsorbent., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Water-bath microwave method was used for hydroxyl ammonium ionic liquids (ILs) synthesis to study the removal of sulfur dioxide (SO(2)) from the flue gas. The results showed that the water-bath microwave method has some advantages of short reaction time and good yields. The synthesis of ethanolamine lactate ILs was fundamentally studied by an orthogonal experiment design (L(9)(3(4))). Based on statistic analysis, it is revealed that the molar ratio of ammonium/acid is the most significant variable, and the optimized preparation conditions are under 338 K, wave power of 300 W for 30 min with the molar ratio 1:1.1 (ethanolamine vs. lactic acid). At the same condition, the yield of the other ILs was over 90% except dimethyl ethanolamine-based ILs. Results showed that the solubility of SO(2) in ethanolamine lactate ILs was 0.51 (mole fraction), higher than others. Ethanolamine lactate ILs was a better absorbent for SO(2). The optimal temperature for the absorption and desorption process were 298 and 363 K, respectively. The optimal desorption time was 60 min. It was also found that water-bath microwave can improve the release of the absorbed SO(2) from ILs., (Copyright (c) 2010 Elsevier B.V. All rights reserved.)

A F-doped vanadia/titania catalyst has been developed by partly substituting the lattice oxygen of the catalyst with fluorine, using NH(4)F as a precursor. The aim of this novel design was to promote the activity of a catalyst with low vanadia loading in the low-temperature selective catalytic reduction of NO with NH(3). Analysis by N(2) physisorption, XPS, ICP, XRD, ESR and PL spectra showed that fluorine doping facilitated the formation of V(4+) and Ti(3+) ions mainly by charge compensation, promoted the distribution of vanadium on the catalyst surface, and increased the amount of surface superoxide ions. The catalytic activity of NO removal was promoted by F-doping. And the catalyst with [F]/[Ti]=1.35 x 10(-2) showed the highest NO removal efficiency in SCR reaction at low temperatures.

The carbon-bearing adsorbents were prepared from biochemical and surplus sludges by physical activation and chemical activation. The results indicated that the adsorbents made by way of chemical activation were better, with the optimum activator being complex of ZnCl(2) and H(2)SO(4). Moreover, the optimum preparation conditions were concentration of two activators 5 mol/L (the ratio of ZnCl(2) and H(2)SO(4) was 2:1), at the activating temperature of 550 degrees C, in the proportion of solid to liquid 1:2.5, in a period of 2h. Contrasting the active carbon, the carbon-bearing adsorbents were characterized by X-ray diffraction (XRD), energy dispersive X-ray spectrometer (EDS), scanning electron microscope (SEM), BET and BJH. By application of those adsorbents to treatment of wastewater of urban, the treatment effect of the carbon-bearing adsorbents were better than the active carbon. On the condition that the concentration was 0.5%, the COD, P and chromaticity color removal rates of carbon-bearing adsorbent made from the biochemical sludge of sewage were higher, which were 79.1, 98.3 and 87.5%, respectively, and the dynamic adsorption capacity was 47.8 mg/g.