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[Display omitted] • Selective photocatalytic removal of a class of PAEs by TiO 2 was firstly realized. • 11 PAEs were selective removed under interference of 33-fold concentration NOM. • Nearly 100% toxicity was removed at selective PAEs-TiO 2 in simulated wastewater. Endowing traditional photocatalysis with selectivity for a class of characteristic pollutants is important in environmental science. Using PAEs-TiO 2 as a selective photocatalyst, 302.5 μg L−1 of 11 phthalic esters (PAEs) were preferentially removed to 4.94 μg L−1 in the presence of 10 mg L−1 of natural organic matter via specific hydrogen bonds or cation-π interactions. Further, degradation of PAEs is a lower risk pathway for PAEs-TiO 2. The in-situ photocatalytic electron paramagnetic resonance initially revealed that PAEs-TiO 2 facilitated the ring opening and mineralization of PAEs, resulting in nearly 100 % detoxification. In actual wastewater, PAEs were not detected after treatment with PAEs-TiO 2. Further, the energy cost was reduced by 48.1 %, reaching discharge standard. This study offers new sights into selective photocatalysis of a class of pollutants with similar molecular structure. [ABSTRACT FROM AUTHOR]

• Atrazine was selectively removed from wastewater with almost 100% detoxification. • Highly specific atrazine recognition relied on halogen bond and hydrogen bond. • Relationship between intermediate and toxicity in atrazine removal was revealed. • Cyanuric acid played an important role in promoting total toxicity elimination. Selective removal of atrazine (ATZ) in wastewater and clarification of the degradation intermediate-toxicity correlation are of great importance. A newly molecularly imprinted, {001} facets-exposed TiO 2 (MI-TiO 2,001) photoanode with strong catalytic and selective ability was designed. ATZ was selectively removed from pesticide wastewater, reaching 1.9 µg L −1, approximately 1/10 of the concentration achieved with nonselective treatment. This selective removal originated from the preferential adsorption and enrichment of ATZ onto MI-TiO 2,001. The highly specific recognition relied on the halogen bond and strong hydrogen bond formed between the Cl atom and triazine ring π orbital of ATZ and the surface -OH group of MI-TiO 2,001 as well as the recognition of MI-TiO 2,001 to the shape and size of ATZ. The specific interaction leads to different accumulations of intermediates. The correlation of intermediate and toxicity was also discussed. Aquatic toxicity was rapidly reduced through the direct dealkylation path, and due to the accumulation of highly toxic 2‑hydroxy-4-ethylamino-6-isopropylamino-s-triazine, there will be transient fluctuations via the dechlorination-hydroxylation path first. The final product was identified as nearly nontoxic cyanuric acid, the selective accumulation of which indicated that there was almost 100% removal of aquatic toxicity and cytotoxicity with only 9.8% removal of total organic carbon. This work provides new insight into the correlation of pollutant degradation intermediates and changes in toxicity. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] Energy consumption from air cooling systems in summer, water scarcity in hot regions, and the functional reusability of waste paper are emerging environmental problems. Finding solutions to these problems simultaneously remains a significant challenge. Herein, a superhydrophobic passive cooling Cellulose-CaCO 3 film with hierarchical nano-sheets was fabricated to realize daytime radiative cooling with a temperature drop of 15–20 °C in summer and water harvesting with harvesting efficiency of 387 mg cm−2h−1 bd utilization of recycled waste paper. The superhydrophobic Cellulose-CaCO 3 film demonstrates its self-cleaning properties against inorganic and organic pollutants. Furthermore, the superhydrophobicity of the film was maintained after base/acid corrosions, dynamic water flushing, and thermal treatment at 100 °C for 7 h, exhibiting good durability of the superhydrophobicity. Moreover, the superhydrophobic Cellulose-CaCO 3 film is nonflammable after exposure to fire combustion for 1 min. In addition to waste paper, waste maize straws, and pasteboards were also collected to produce superhydrophobic passive cooling films. Results indicate that the above three cellulose-based raw materials can be well used to prepare durable superhydrophobic passive cooling materials. Environmental toxicology assessments confirm the safety of the material. This study not only provides a protocol for preparing superhydrophobic materials; but also demonstrates their potential for passive cooling and water harvesting. [ABSTRACT FROM AUTHOR]

• Electrochemical system catalyzes sulfate for in situ generation of SO 4 −. • Synergistic radical generation mechanism at cathode and anode is firstly clarified. • Co 3 O 4 NWs arrays with the fast electron transport to efficiently activate persulfate. • The electrically accelerated circulation of Co(III)/Co(II) sustained the stability. Sulfate-based electrochemical advanced oxidation is of rising importance for pollutant removal, however, adscititious sulfate has adverse effects on water salinity. A novel electrochemical system which could exploit the existed SO 4 2− for in situ generation of SO 4 − was successfully constructed with boron doped diamond (BDD) anode and hierarchical 1D Co 3 O 4 nanowire array cathode. The in situ electrochemical electron paramagnetic spectroscopy and titration were used to study the positive correlation between the increase of sulfate radicals (SRs) and the efficient activation of peroxydisulfate (PDS) by hierarchical 1D Co 3 O 4 nanowire array cathode. Electrochemical impedance and X-ray photoelectron spectroscopy revealed that the efficient activation of PDS by the Co 3 O 4 cathode was derived from the excellent electron transport capability of the 1D nanostructure, and the electric field accelerates the reduction of Co(III). The novel hierarchical 1D Co 3 O 4 nanowire array cathode can completely degrade dibutyl phthalate in 45% less time with 38% less energy compared to a traditional graphite cathode without the requirement of extra chemicals. The possible mechanism of anodic PDS accumulation and cathodic SRs generation was firstly revealed, and this advanced electrochemical oxidation system provides a good reference for the in situ sustainable remediation in sulfate-containing water. [ABSTRACT FROM AUTHOR]

Reuse of agricultural and industrial wastes simultaneously to prepare hydrochars (HCs) for removal of NH 4 + and PO 4 3− in practical sewage without additional wastes produced is still a challenge. Herein, HCs were fabricated by combination of rape straw and industrial sewage sludge to remove NH 4 + and PO 4 3− from hoggery effluent. Synthesis conditions were firstly optimized and optimized HC (OPT-HC) was further applied to adsorb NH 4 + and PO 4 3−. Monolayer and Pseudo-first-order as well as Pseudo-second-orders were confirmed via adsorption kinetic and isothermal adsorption studies. Morphologies and surface areas of the OPT-HC did not show any transformations before and after adsorption of NH 4 + and PO 4 3−. The OPT-HC after adsorption of NH 4 + and PO 4 3− (OPT–HC–N/P) was further applied as fertilizer for planting Ping-pong Chrysanthemum. Results indicate that the OPT–HC–N/P can improve comprehensive qualities of the Ping-pong Chrysanthemum such as plant height, fresh, Vitamin C, Chlorophyll, soluble protein and sugar because the OPT–HC–N/P can provide extra N and P elements and also promote to release available K in soil. OPT–HC–N/P treated Ping-pong Chrysanthemum open flowers in advance. Thus, two kinds of wastes were re-utilized to remove N and P in real-life effluent. • Agricultural and industrial wastes were used to prepare hydrochars. • The hydrochars can be applied to remove N and P in hoggery effluent. • No wastes produced after removal of N and P. • Horticultural/agricultural applications were further realized. • Qualities of Ping-pong Chrysanthemum improved by HC after adsorption of N and P. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel MM–TCMRs were synthesized for concurrent removal of phosphate and ammonium. • MM–TCMRs exhibits excellent phosphate and ammonium adsorption capacity. • Potential phosphate and ammonium removal mechanism with MM–TCMRs was proposed. • >70 % phosphate and ammonium were recovered from swine wastewater after four cycles. • Nutrient–loaded MM–TCMRs is applied as a fertilizer to promote alfalfa growth. Magnetic magnesium (Mg)–loaded Chinese herbal medicine residues (MM–TCMRs) were fabricated to simultaneously remove and recover phosphate and ammonium from wastewater. The MM–TCMRs exhibited larger specific surfaces and rougher structures with massive spherical particles than those of original residues. They could be separated by adjusting the magnetic field. The phosphate and ammonium adsorption by MM–TCMRs were matched with the pseudo–second–order model, while the Langmuir model yielded the maximum adsorption capacities of 635.35 and 615.57 mg g−1, respectively. Struvite precipitation on the MM–TCMRs surface was the primary removal mechanism with electrostatic attraction, ligand exchange, intra–particle diffusion, and ion exchange also involved. The recyclability of MM–TCMRs confirmed their good structural stability. More importantly, the nutrient–loaded MM–TCMRs enhanced alfalfa growth and improved soil fertility in planting experiments. Collectively, the MM–TCMRs are promising candidates for nutrient removal and recovery from wastewater. [ABSTRACT FROM AUTHOR]

In order to mitigate the harmful effects of eutrophication in water bodies, the applications of lanthanum-modified materials for phosphate removal from wastewater have attracted much attention. Unlike conventional adsorbents, plant wastes usually have poor adsorption abilities and are difficult to be reused for desorption of phosphate due to their small pore sizes and ununiform loading of modified ions. In this paper, a composite adsorbent (LC-MM) was synthesized by hydrothermal treatment of waste traditional Chinese medical materials (MMs) with load of lanthanum carbonate and co-heating treatment with coal fly ash (CFA), which was applied to remove phosphate from water. The results showed that maximum adsorption capacity of LC-MM was 52 mg g−1, and the LC-MM showed appreciable adsorption capacity of phosphate for agricultural wastewater in the presence of complex interfering ions and for urban surface waters with low phosphate concentrations. Five adsorption-desorption cycles showed good reusability. The mechanism study showed that the La3+ ions were more uniformly distributed on the surface of the absorbents with the introduction of Fe3+, Al3+, Mg2+ and Ca2+ ions in CFA. The ligand exchange between phosphate and carbonate, the internal spherical complexation formed by lanthanum ion and phosphate, and surface chemical precipitation attachment are the main reasons why the adsorption capacity of LC-MM approached or even surpassed that of conventional lanthanum-modified adsorbents. In conclusions, this work proposed an effective method for the modification of plant materials. [Display omitted] • Reuse of two types of waste after treatment. • A method to improve the inefficiency of phosphate adsorption by plant materials. • The mechanism of modification is to influence the state of lanthanum on the surface of the carrier. • Effect of phosphate separated after adsorption on plant growth. [ABSTRACT FROM AUTHOR]

In order to mitigate the harmful effects of eutrophication in water bodies, the applications of lanthanum-modified materials for phosphate removal from wastewater have attracted much attention. Unlike conventional adsorbents, plant wastes usually have poor adsorption abilities and are difficult to be reused for desorption of phosphate due to their small pore sizes and ununiform loading of modified ions. In this paper, a composite adsorbent (LC-MM) was synthesized by hydrothermal treatment of waste traditional Chinese medical materials (MMs) with load of lanthanum carbonate and co-heating treatment with coal fly ash (CFA), which was applied to remove phosphate from water. The results showed that maximum adsorption capacity of LC-MM was 52 mg g−1, and the LC-MM showed appreciable adsorption capacity of phosphate for agricultural wastewater in the presence of complex interfering ions and for urban surface waters with low phosphate concentrations. Five adsorption-desorption cycles showed good reusability. The mechanism study showed that the La3+ ions were more uniformly distributed on the surface of the absorbents with the introduction of Fe3+, Al3+, Mg2+ and Ca2+ ions in CFA. The ligand exchange between phosphate and carbonate, the internal spherical complexation formed by lanthanum ion and phosphate, and surface chemical precipitation attachment are the main reasons why the adsorption capacity of LC-MM approached or even surpassed that of conventional lanthanum-modified adsorbents. In conclusions, this work proposed an effective method for the modification of plant materials. [Display omitted] • Reuse of two types of waste after treatment. • A method to improve the inefficiency of phosphate adsorption by plant materials. • The mechanism of modification is to influence the state of lanthanum on the surface of the carrier. • Effect of phosphate separated after adsorption on plant growth. [ABSTRACT FROM AUTHOR]

One important pathway for human exposure to per- and polyfluorinated alkyl substances (PFASs) is based on the Earth's atmosphere. Figuring out atmospheric transformation mechanism of PFASs is beneficial for understanding their effects on humans. However, the focus on the molecular-level transformation mechanism of emerging PFASs in the atmosphere still need to be improved. In this work, we used quantum chemistry calculation to study ·OH-initiated degradation mechanism of a new fluorinated alcohol (C 3 F 7 OCHFCF 2 SCH 2 CH 2 OH, abbreviated FESOH) in the presence of oxygen and nitric oxide. Three main conformers of FESOH share the similar initial mechanism that the abstraction reactions of H atom at α-C and β-C atoms are the main pathways (activation free energies of <10 kcal mol−1 at 298 K), but make different contributions to the whole FESOH degradation. Subsequent transformations starting from initial products at α-C atoms will reunite with that at β-C atoms, and the intermediate (C 3 F 7 OCHFCF 2 S·) is produced. After O 2 addition to the intermediate and the following SO 2 elimination, the alkyl radical (C 3 F 7 OCHFCF 2 ·) can undergo consecutive chain cleavage cycles to form CF 3 OH finally. The bioaccumulation evaluation shows that FESOH and its transformation products cannot be accumulated in organisms. The work is helpful for knowing the atmospheric fate of FESOH at molecular level and can provide some insight into the transformation of other PFASs in the atmosphere. [Display omitted] • Three main conformers of FESOH account for approximate 99% of all conformers. • The H-abstraction at α-C and β-C mainly occurs for ·OH-initiated FESOH degradation. • Subsequent reactions can form alkyl peroxynitrite, fluorinated aldehyde and CF 3 OH. • FESOH and its transformation products cannot be accumulated in organisms. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) broadly coexist with heavy metals (HMs) in soil, Cd and Cu are the main types of soil HMs contamination, in addition to polystyrene (PS), which is also widely present in the environment and prone to aging. However, differences in the effects of MPs and HMs on soil properties and microbial characteristics under alternating wetting and drying (AWD) remain unclear. Thus, this study investigated the effects of four conventional (0.2% (w/w)) and aged MPs in indoor incubation experiments on soil properties under desiccation (Dry) and AWD. We found that with the influence of the "enzyme lock" theory, the coexistence of MPs and HMs under Dry had a more pronounced effect on soil physicochemical properties, whereas the effects on soil enzyme activity under AWD were more significant. In addition, MPs decreased the available Cu by 4.27% and, conversely, increased the available Cd by 8.55%. Under Dry , MPs affected microbial function mainly through physicochemical properties, with a contribution of approximately 72.4%, whereas under AWD enzyme activity and HMs were significantly greater, with increases of 28.2% and 7.9%, respectively. These results indicate that the effects of MPs on environmental variation and microbial profiles under AWD conditions differed significantly from those under Dry. [Display omitted] • Microplastics (MPs) under Dry effect more on physicochemical properties. • More evident effects of MPs on soil enzyme activities/heavy metals (HMs) under AWD. • The effects of MPs on soil microbial structure were more significant under AWD. • Combined contamination of MPs and HMs under AWD effect more on microbial functions. • Greater impact of enzyme activity and HMs on microbial function under AWD. [ABSTRACT FROM AUTHOR]

The removal of a class of toxic thiol-containing heterocyclic pollutants from complex water matrices has great environmental significance. In this study, a novel photoanode (Au/MIL100(Fe)/TiO 2) with dual recognition functions was designed for selective group-targeting photoelectrocatalytic removal of thiol-containing heterocyclic pollutants from various aquatic systems. The average degradation and adsorption removal efficiency of 2-mercaptobenzimidazole, 2-mercaptobenzothiazole, and 2-mercaptobenzoxazole were still above 96.7% and 13.5% after selective treatment with Au/MIL100(Fe)/TiO 2 even coexisting with 10-fold concentration of macromolecular interferents (sulfide lignin and natural organic matters) and the same concentration of micromolecular structural analogues. While they were below 71.6% and 3.9% after non-selective treatment with TiO 2. Targets in the actual system were selectively removed to 0.9 µg L−1, which is 1/10 of that after non-selective treatment. FTIR, XPS and operando electrochemical infrared results proved that the highly specific recognition mechanism was mainly attributable to both the size screening of MIL100(Fe) toward targets and Au-S bond formed between -SH group of targets and Au of Au/MIL100(Fe)/TiO 2. •OH are the reactive oxygen species. The degradation mechanism was further investigated via excitation-emission matrix fluorescence spectroscopy and LC-MS. This study provides new guidelines for the selective group-targeting removal of toxic pollutants with characteristic functional groups from complex water matrices. [Display omitted] • Fabrication of a novel Au/MIL100(Fe)/TiO 2 photoanode with dual recognition functions. • Thiol-containing heterocyclic targets were selectively removed from water matrices. • Highly specific recognition relied on the size screening and Au-S bond. • Providing insights for selective removal of toxic group-targeting pollutants. [ABSTRACT FROM AUTHOR]

The disposal of electroplating sludge (ES) is a common concern of researchers. Currently, it is difficult to achieve effective fixation of heavy metals (HMs) using traditional ES treatment. As green and effective HMs removal agents, ionic liquids can be used for the disposal of ES. In this study, 1-butyl-3-methyl-imidazole hydrogen sulphate ([Bmim]HSO 4) and 1-propyl sulphonic acid-3-methyl imidazole hydrogen sulphate ([PrSO 3 Hmim]HSO 4) were used as washing solvents for the removal of Cr, Ni, and Cu from ES. In reaction with increased agent concentration, solid–liquid ratio, and duration, the amount of HMs eliminated from ES rises, whereas opposite patterns were shown in response to rising pH. The quadratic orthogonal regression optimisation analysis also revealed that the ideal washing specifications for [Bmim]HSO 4 were 60 g L−1, 1:40, and 60 min, respectively, for agent concentration, solid–liquid ratio, and washing time, while those for [PrSO 3 Hmim]HSO 4 were 60 g L−1, 1:35, and 60 min, respectively. Under the optimal experimental conditions, the Cr, Ni, and Cu removal efficiencies for [Bmim]HSO 4 were 84.3, 78.6, and 89.7%, respectively, and those values for [PrSO 3 Hmim]HSO 4 were 99.8, 90.1, and 91.3%, respectively. This was mainly attributed to that ionic liquids enhance metal desorption through acid solubilisation, chelation, and electrostatic attraction. Overall, ionic liquids are reliable washing reagents for ES contaminated by HMs. [Display omitted] • Ionic liquids exhibited efficient Cr, Ni and Cu removal from electroplating sludge. • Effect of various experimental conditions on heavy metals removal was explored. • Removal mechanism of ionic liquids to heavy metals was described. • The finding will provide new ideas for the disposal of electroplating sludge. [ABSTRACT FROM AUTHOR]

Carbon aerogel (CA) was used in electrosorption to enhance Bi 2 WO 6 photoelectrocatalytic process for trace amount (1 mg/L) nonylphenol (NP) elimination. The composite Bi 2 WO 6 /CA electrode fabricated with CA as adsorbent and Bi 2 WO 6 as photocatalyst was found to be effective to achieve the synergy of electrosorption and photoelectrocatalysis. At alkaline pH (>12), more than 90% of NP was adsorbed by applying potential lager than 0.6 V ( vs. SCE), most of which was gathered on the electrode. Electrosorption was promoted with increasing of electric field intensity and pH. NP gathered on the electrode was degraded completely (99.3%) in the photoelectrocatalytic process due to electrosorption enrichment and well photocatalytic properties of the electrode. The degradation efficiency depended largely on the electrosorption process, thus the removal of NP was also affected by pH and applied potentials. The electrode achieved “self-cleaning” due to synergistic effect of electrosorption and photoelectrocatalysis: electrosorption was favorable for photocatalytic degradation and the photocatalytic degradation can renew the electrode after the adsorbed pollution was removed. Trace NP can be eliminated efficiently in real sample, and the final concentration of NP was below 6.4 μg/L, which meet the effluent standard of NP. [ABSTRACT FROM AUTHOR]