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Reutilization of spent adsorbent by converting the adsorbed organic pollutants into carbon matrix has attracted more attention in recent years, which delivers a greener way for the preparation of catalysis and environment remediation. In this work, CuBi 2 O 4 after adsorption of pollutant sulfamethazine was further transformed to a photocatalyst CBO-WC500 with high catalytic efficiency for degradation of typical pharmaceuticals. The XAFS analysis proved that Cu-C chemical bond was constructed during the preparation process. The obtained CBO-WC500 was applied to remove sulfamethoxazole (SMX) through photocatalytic Fenton-like reaction, and removal efficiency reached 88.9 % after 60 minutes with the initial 5 mg•L−1 SMX and 0.2 g•L−1 catalyst in peroxymonosulfate (PMS) system. The results showed that the introduction of carbon stem from waste improved separation of photo-generated carriers and electron transfer capability, thus more photo-induced electrons could participate in reaction with PMS. Moreover, Cu(I) and Cu(II) in CBO-WC500 with Cu-Bi-spinel structure played a vital role in PMS activation. Led by electron transportation, reactive species (1O 2 , •OH, SO 4 •-) originated from PMS contributed to degradation of SMX, and degradation pathway of target pollutant was proposed based on analysis of intermediates. Removal efficiency of CBO-WC500 for SMX kept stable after several cycles' utilization, and it also showed decent eliminating performance of mixed pollutants in different water matrix. This study has provided a potential way for resource reuse of adsorbed pollutant and realizing reutilization of spent adsorbent as photocatalyst with higher efficiency. [Display omitted] • A novel CBO-WC500 catalyst regenerated from sulfamethazine-adsorbed CuBi 2 O 4 adsorbent. • The CBO-WC500 material exhibited high photocatalytic activating PMS capability. • Electron transfer was dominant mechanism in catalysis degradation reaction of SMX. • Mixed pollutants of four pharmaceuticals in natural water were efficiently removed. [ABSTRACT FROM AUTHOR]

In this research, ethylene glycol-introduced solvothermal method was employed to fabricate a novel sphere-like CuBi2O4 material to improve the adsorptive and photocatalytic performance of conventional CuBi2O4. A series of characterization has been applied to investigate properties of the obtained CuBi2O4 (CBO-EG3). Compared with conventional rod-like CuBi2O4 (CBO), the synthesized sphere-like CBO-EG3 exhibited rough surface, larger specific surface area, and more effective separation of photo-generated carriers, which overcome main shortcomings of CuBi2O4. The removal efficiency of typical antibiotic sulfamethazine (SMZ) reached almost 100% under the optimal experimental conditions. About 70% of SMZ could be adsorbed in 180-min dark reaction, with residual being photodegraded in 30 min. CBO-EG3 showed much higher photocatalytic efficiency than pure CBO, attributing to its highly effective photo-induced electron and hole separation. Meanwhile, substantial adsorption of pollutant on CBO-EG3 contributed vastly to removal of SMZ, photo-generated electrons and holes inclined to react with adsorbed SMZ directly, and photocatalytic process was mainly led by non-radical reaction. Elimination of SMZ in actual water samples and recycling experiment were also performed to evaluate CBO-EG3's practical application potential. This study delivered a method to promote CuBi2O4's adsorptive and photocatalytic ability, which could expand the application of CuBi2O4 in wastewater treatment. [ABSTRACT FROM AUTHOR]

As an important part of the residents' diet in China, the consumption of hen and duck eggs has been increasing rapidly in the past decades. Being rich in protein and lipid, eggs may be one of the main exposure routes for persistent organic pollutants (POPs) to human beings. In this study, four kinds of free-range hen and duck eggs were collected from two traditional egg-producing areas in Shanghai, namely Dianshan Lake Area and Jinshan Industry Zone. Organochlorine pesticides (OCPs, 18 compounds) and polychlorinated biphenyls (PCBs, 14 compounds) were analyzed with 41 egg samples. Among all OCPs, dichlorodiphenyltrichloroethanes (DDTs) were the dominant contaminant, with the concentrations ranging from 100 to 730 ng/g, lw. Unlike the 4,4′-DDE as the predominant DDTs congener in other three kinds of eggs, the duck eggs from Jinshan Industrial Zone had an abnormally high concentration of 2,4′-DDD, which may be related to ducks' feedings in the water. The levels of hexachlorocyclohexanes (HCHs) and pentachloroanisole (PCA) in eggs from different places were similar to each other, while hexchlorobenzene (HCB) for hen eggs from Dianshan Lake was much higher than other eggs. According to the results, the DDTs residues detected in this study were mainly due to the historical usage, whereas the high ratio of γ-HCH/α-HCH suggested that there might be some recent input of lindane in these two areas. For PCBs, the congener profiles varied among species. Low molecular PCBs (Tri-PCBs and Tetra-PCBs) were main congeners for duck eggs from Dianshan Lake and all hen eggs, while high molecular PCBs accounted for more than 50 % for duck eggs from Jinshan Industrial Zone, which was consistent with the water analysis results of the synchronous study from our group. This study suggests that Dianshan Lake Area may not be a good reference area for POPs monitoring in Shanghai. The estimated daily intakes of DDTs, HCHs, HCBs, and PCBs were far below the reference limits, showing no significant health risk for human consumption by eating eggs collected in this study. [ABSTRACT FROM AUTHOR]

The global contamination with persistent organic pollutants (POPs), or compounds with similar characteristics, is well known. Still there are data gaps for POP concentrations from many areas in the world. The aim of the present study is to assess several legacies POPs and also hexabromocyclododecane (HBCDD) and methoxylated polybrominated diphenyl ethers (MeO-PBDEs) in shellfish from three locations in the Yellow Sea and East China Sea. The sources of the contaminants are discussed. Pooled samples were treated by liquid-liquid extraction and acid and column cleanup prior to analysis by gas chromatogram equipped with electron capture detector (GC-ECD) and gas chromatography-mass spectrometry (GC-MS). The by far most abundant environmental contaminant originates from dichlorodiphenyltrichloroethane (DDT), independent of species analyzed or sampling site. The results indicate ongoing or at least recent discharges of DDT. The second highest concentrations were reported for HBCDD (21-40 ng/g fat) in the shellfish, independent of sampling sites. The two natural products, 6-MeO-BDE-47 and 2′-MeO-BDE-68, were also present in the shellfish (1.3-22 and 1-14 ng/g fat, respectively). The polychlorinated biphenyl (PCB) congener CB-153 (0.8-6.5 ng/g fat), hexachlorobenzene (HCB) (1.1-3.6 ng/g fat), and β-hexachlorocyclohexane (β-HCH) (2.3-4.9 ng/g fat) were all higher than the concentrations of other HCH isomers, β-endosulfan, PBDE congeners, and mirex. Apart from the DDTs and HBCDDs, it is evident that the pollution of shellfish was similar to, or lower than, the contamination of shellfish in other parts of the world. [ABSTRACT FROM AUTHOR]

Abstract: In the present study were two favorite edible fish species for local residents, i.e., mandarin fish and crawfish, collected from the Shanghai market and analyzed for selected organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), hexabromocyclododecane (HBCDD), polybrominated diphenyl ethers (PBDEs) and methoxylated PBDEs (MeO-PBDEs). Efforts were also made to identify the potential sources of these contaminants. Comparable concentrations of hexachlorocyclohexanes (HCHs), dichlorodiphenyltrichloroethanes (DDTs) and HBCDD were found in muscle tissue of mandarin fish from Guangdong (GDF), the Pearl River Delta and from Taihu Lake (TLF), the Yangtze River Delta. Levels of chlordanes, PCBs and PBDEs were about one magnitude lower in TLF compared to GDF. The concentrations of OCPs in the butter-like gland of the crawfish (CFB) were 2–5times of those in the crawfish muscle (CFM) while concentrations of PCBs, PBDEs and MeO-PBDEs were comparable. The different patterns and levels of chlorinated and brominated organohalogen contaminants seen in mandarin fish from GDF and TLF indicates that different types of chemicals might be used in the two delta regions. The present study also shows a good correlation between the concentrations of hexachlorobenzene (HCB) and pentachloroanisol (PCA) in fish for the first time. Fish consumption limits based on chemical contaminants with non-carcinogenic effects were calculated. The estimated maximum daily consumption limit for GDF, TLF, CFM and CFB were 1.5, 2.6, 3.7 and 0.08kg, respectively, indicating no significant risk regarding the persistent organic pollutants measured in the present study. [Copyright &y& Elsevier]

The article Chlorinated and brominated organic pollutants in shellfish from the Yellow Sea and East China Sea, written by Ge Yin, Lillemor Asplund, Yanling Qiu, Yihui Zhou, Hua Wang, Zongli Yao, Jianbin Jiang and Åke Bergman [ABSTRACT FROM AUTHOR]

Background: Freshwater sediments have been recognized as a long-term sink and potential source for environmental pollutants released into the aquatic ecosystems. In this study, the sediment quality of Taihu Lake, which is susceptible to anthropogenic contamination, was assessed by a combination of chemical analytical and biological end points. Specifically, the snail Bellamya aeruginosa was caged in situ at two locations representing different pollution levels for different exposure times (7, 14 and 21 days). At each of these time points, biochemical parameters, i.e., phase I biotransformation enzymes ethoxyresorufin-O-deethylase (EROD), the antioxidant enzymes superoxide dismutase and catalase, reactive oxygen species, protein carbonyl content and lipid peroxidation, were evaluated in the hepatopancreas of snails. In addition, surface sediments were collected for analysis of contaminants of concern, including inorganic pollutants, organochlorine pesticides, polychlorinated biphenyls and polybrominated diphenyl ethers.Results: Chemical analyses revealed that sediments from Taihu Lake were contaminated with trace elements and organic pollutants. Concentrations of trace elements (Cu, Ni and As) and organochlorinated pesticides (4,4′-DDE) exceeded their corresponding threshold effect level according to the sediment quality assessment values for freshwater ecosystems in Canada, indicating that adverse biological effects may occur. All biomarkers, except EROD activity, were induced in snails during all exposure times. The integrated biomarker response index (IBR) indicated that during the initial exposure phase (7 days), B. aeruginosa were subjected to significant environmental stress, which diminished during later sampling time points.Conclusions: Results showed that IBR correlated well with the levels of environmental contaminants, demonstrating the applicability of this biomonitoring approach to complex environmental exposure scenarios. [ABSTRACT FROM AUTHOR]

The magnetic field is a special substance that exists objectively and transmits the magnetic force between objects. Magnetic fields (MFs) are gradually attracting attention as a facile, universal adsorption enhancement method, especially under the condition of low concentration of pollutants. By adjusting the type and parameters of the magnetic field, enhancement of adsorption capacity, rate and selectivity can be targeted. Many studies have focused on the adsorbent separation based on magnetic properties under MF assistant, and no review have come up in recent years on the pollution enhanced-adsorption technique using MFs. The present review brings out a series of magnetic field and summarizes adsorption-assisted enhancement mechanism of MFs in different situations. This review article aimed at helping researchers obtain quick ideas of MFs and application for pollutant adsorption. ga1 • Magnetic fields (MFs) is a facile, universal adsorption enhancement method. • Enhancement of adsorption capacity, rate and selectivity can be targeted under MFs. • No review have come up in recent years on MF-enhanced-adsorption technique. • Summarize MF assisted-enhancement mechanism on adsorption. • Challenges and development prospects of MF-enhanced-adsorption are outlooked. [ABSTRACT FROM AUTHOR]

[Display omitted] • Porous single Fe atom catalyst with FeN 4 O 1 moiety was successfully fabricated. • High spin (HS) state of Fe(II) induced abundant electron density around Fe centers. • Electron transfer occurred between FeN 4 O 1 sites, adsorbed PMS and organics. • Optimized Fe SA -N/O C/PMS system showed superior oxidation performance for organics. • Fe SA -N/O C catalyst presented well stability, reusability and applicable potential. The construction of single Fe atoms with favorable electron structures is highly desired to boost peroxymonosulfate (PMS) activation for organics degradation. Herein, this study embedded isolated Fe atoms on N, O co-doped porous carbon substrate (Fe SA -N/O C), and first found the constructed FeN 4 O 1 configuration can realize efficient PMS activation via electron transfer by inner-sphere complexation, instead of the usual reactive oxygen species (ROS) as a major role. Structural investigation showed that the FeN 4 O 1 moieties possess high content of high spin (HS) Fe(II), resulting in the delocalization of unpaired electrons around Fe centers, which is benefit to transfer electrons when reacted with PMS. EIS and LSV curves further certified the electron transfer process. Density functional theory (DFT) calculations unveiled that the FeN 4 O 1 configuration can directly adsorb O O bond of PMS, leading to electron accumulation around Fe-O 2 bond, and then ulteriorly trigger the electron shuttling in organics degradation. Consequently, the optimized Fe SA -N/O C/PMS system exhibited superior oxidation ability for various organic pollutants, and was not affected by initial pH variation (3.19 ∼ 10.89), inorganic anions (ClO 4 −, Cl− and H 2 PO 4 −) and natural organic matter (NOM) interference. Importantly, the developed system presented certain applicability in the treatment of actual water from Taihu Lake basin, China. Hence, this study not only elucidates the inner-sphere complexation-oriented electron transfer mechanism between unique FeN 4 O 1 configuration and PMS, but provides new insights into engineered single atom catalysts for wastewater purification. [ABSTRACT FROM AUTHOR]

The environmental and human health concerns for organohalogen contaminants (OHCs) extend beyond the 23 persistent organic pollutants (POPs) regulated by the Stockholm Convention. The current, intense industrial production and use of chemicals in China and their bioaccumulation makes Chinese wildlife highly suitable for the assessment of legacy, novel and emerging environmental pollutants. In the present study, six species of amphibians, fish and birds were sampled from paddy fields in the Yangtze River Delta (YRD) were screened for OHCs. Some extensive contamination was found, both regarding number and concentrations of the analytes, among the species assessed. High concentrations of chlorinated paraffins were found in the snake, Short-tailed mamushi (range of 200–340 μg g − 1 lw), Peregrine falcon (8–59 μg g − 1 lw) and Asiatic toad (97 μg g − 1 lw). Novel contaminants and patterns were observed; octaCBs to decaCB made up 20% of the total polychlorinated biphenyls (PCBs) content in the samples and new OHCs, substituted with 5–8 chlorines, were found but are not yet structurally confirmed. In addition, Dechlorane 602 (DDC-DBF) and numerous other OHCs (DDTs, hexachlorocyclohexanes (HCHs), polybrominated diphenyl ethers (PBDEs), hexbromocyclododecane (HBCDD), chlordane, heptachlor, endosulfan and Mirex) were found in all species analyzed. These data show extensive chemical contamination of wildlife in the YRD with a suite of OHCs with both known and unknown toxicities, calling for further in-depth studies. [ABSTRACT FROM AUTHOR]

[Display omitted] • Bamboo-shaped 3D tubular structures were constructed in a Fe–nitrogen–doped carbon, Fe–N–C. • Dual active sites of atomic Fe cluster and Fe–N configuration coexist in Fe–N–C. • Fe–N–C showed high PMS activation to the degradation of various aromatic pollutants. • Radical and non-radical reaction pathways contributed to different sites in Fe–N–C/PMS. • The structure-activity-stability relationship is proposed based on Fe–N–C/PMS-coupled process. Fenton-like catalysis has received much attention as the promising technology for organic pollutant degradation, whereas it suffers from low atomic utilization, poor catalysts durability and difficult after-treatment to hamper the catalytic oxidation activity. Herein, a Fe– and nitrogen-codoped carbon (Fe–N–C) originated from nanocellulose-based hydrochar, nitrogen source, and iron salt precursor was developed for improved PMS activation and identification of exclusive role of each species. The catalyst formed with interconnected bamboo-shaped 3D tubular structures and high Fe-doping level (up to ~9.0 wt%) not only realized excellent efficiencies in oxidative degradation of various aromatic pollutants, but was also endowed with high durability and stability toward PMS activation. Compared with that of the control catalysts only comprising either C–N network or supported Fe nanoparticles (Fe–C) with FeIV–oxo complex sites, the co-existent active sites of Fe–N configuration and atomic Fe cluster in Fe–N–C could simultaneously improve the graphitization degree, and act as a "support" for constructing the stable structure. It is likely that the coordinated Fe–N formed with annealing process is devoted to decompose PMS by radical generation for pollutants degradation via a radical oxidation process; while the enhanced C–N bonded with graphitic N contribute to produce 1O 2 through the nonradical processes interacted with PMS. This Fe–N–C/PMS-coupled process provided a designed strategy to construct the highly active and stable metal-nitrogen-codoped hydrothermal carbons, and deepened insights on structure-activity-stability relationship for persulfate-based environmental remediation. [ABSTRACT FROM AUTHOR]

[Display omitted] • A series of Cu-O-CN materials were prepared by one-pot calcination method. • C-O groups were evidenced as adsorption sites to benefit subsequent catalysis. • Electron transfer occurred through the constructed C-O-Cu linkage. • Cu-O-CN-100/PMS system exhibits excellent performance for BPA degradation. • Synergistic mechanism of adsorption and catalysis was proposed for BPA removal. Construction of active adsorption and catalytic sites is an effective approach to promote adsorption and heterogeneous catalysis. However, developing high efficient catalyst and exploring the systematic mechanism are still long-term objectives for practical application. Herein, a unique strategy of Cu-O-incorporation into g-C 3 N 4 framework (Cu-O-CN) was proposed, the obtained catalyst was employed as efficient PMS activator for the affluent active sites and ascendant redox behaviors. The mechanistic study showed the introduced oxygen was in the form of C-O groups, acted as the center of the active sites, to adsorb pollutants for subsequent catalysis. After PMS addition, the redox cycle of Cu2+/Cu+ was triggered by electron transfer via fabricated C-O-Cu linkage, resulting in the generation of SO 4 •– and 1O 2 for direct pollutants degradation. Consequently, the screened Cu-O-CN-100/PMS reaction system was capable enough towards bisphenol A (BPA) elimination, and the ratios of adsorption and catalysis accounted for 32.6% and 67.0%, respectively, through BPA removal ratio calculation. Moreover, this reaction system exhibited widely applicable pH range and potential ability towards actual water purification. This study can provide a valuable insight for efficient synergistic effect of adsorption and catalysis by Cu-O-incorporated design, and is of great significance to broaden the practical application for water treatment. [ABSTRACT FROM AUTHOR]

• N-doping of biochar induced a variation of persistent free radicals (PFRs). • Different types of PFRs were found on hydrochar and N-doped hydrochar (NHC). • NHC was a robust catalyst for degradation of endocrine disrupting compounds. • Graphitic N played a role in both radical and nonradical pathways for the degradation. Metal-free carbocatalysts are raising increased interest in advanced oxidation processes (AOPs) for green degradation of aqueous organic pollutants. In the present study, a series of N-doped hydrochars (NHCs) was prepared from pinewood biomass and used in carbocatalysis toward catalytic peroxymonosulfate (PMS) activation to degrade refractory endocrine disrupting compounds. Nitrogen-doping was found to regulate the concentrations and types of persistent free radicals (PFRs) on hydrochar, promoting the electron transfer and oxidative degradation of the contaminants. Mechanistic studies revealed that graphitic N not only shows a strong electron transfer to facilitate PMS activation in a nonradical pathway, but also induces the formation of oxygen-centered PFRs from the structure defects for a radical oxidation pathway. More importantly, the PMS/NHC system demonstrates efficient degradation and satisfactory stability for real water treatment. This study has gained in-depth understanding on the roles of N-dopants in radical and nonradical pathways of biomass-based carbocatalysis, and will provide a promising and environmental-friendly route for efficient degradation of refractory endocrine disrupting compounds for green remediation. [ABSTRACT FROM AUTHOR]