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• The nanofiber composites are prepared for high-performance interface evaporation. • Dual-ion channels ensures simultaneous steam generation and heavy metal ion removal. • Solar driven interface evaporation promotes the Cr (VI) adsorption. Solar driven interfacial evaporation (SDIE) is promising in harvesting fresh water because of its low cost, environmental friendless and sustainability; however, it is desirable but still difficult to achieve high efficiency heavy metal ion removal during SDIE. Here, we develop a superhydrophilic and stretchable nanofiber composite solar evaporator via carbon nanofiber (CNF) assembly on polymer fiber surface and then polydopamine (PDA) modification. The evaporation rate reaches as high as 1.456 kg m−2 h−1 with the evaporation efficiency of 91.40 %. The functional groups of PDA endow the nanofiber composite with good heavy metal ion adsorption performance that is proved to be an endothermic process, and SDIE can induce the increase of interface temperature and localized ion concentration and hence promote the Cr (VI) adsorption. One the other hand, NaCl ions are able to diffuse into body water without salt precipitation by virtue of powerful water transportation capability of the evaporation device. The dual Cr (VI) adsorption and NaCl ion diffusion channels ensure simultaneous and high efficiency Cr (VI) removal and seawater interface evaporation. SDIE accelerated heavy metal ion adsorption and the dual ion channel model provide inspiration to design multifunctional solar evaporator materials for waste water purification. [ABSTRACT FROM AUTHOR]

[Display omitted] • Biosynthesis of bacterial cellulose as greener materials for water treatment. • Tailored functionalization without effecting the natural fibrillar structure of BC. • Excellent removal efficiency for Cd2+ and Cr3+ ions from aqueous medium. • Repeated reuse potential with flux recovery of more than 90%. Bacterial cellulose (BC) membranes produced from biomass are emerging as an eco-friendly solution for water decontamination. The abundance of hydroxyl groups and the high surface-to-volume ratio of this material allow for the integration of diverse functional groups, providing the potential for targeted water purification applications. Beyond their intriguing mechanical properties and unique complex structure, bacterial cellulose membranes are biodegradable into sugar molecules and can be processed with minimal handling and using mild chemicals. Taken together, these features make them a compelling choice for water filtration in the context of environmental responsibility. In their natural state, BC membranes have limited potential for targeted wastewater treatment. One strategy for enhancing their functionality is to graft customized molecules onto their surface. Therefore, this study aims to impart multifunctionality to BC membrane for water filtration. Hence a novel precursor with hard and soft base functionalities consisting of amines, carbonyls, amides, hydroxyls etc. is designed and grafted onto BC membranes, grown to ensure surface uniformity and membrane-to-membrane repeatability of the properties. The structure of the synthesized precursors and the effective functionalization of the membrane are then validated through various structural characterization techniques. Changes in the morphology of BC membranes are examined using Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM). Both the pristine and modified BC membranes undergo a series of tests to assess their filtration capabilities under low-pressure regime and their efficiency in removing representative cadmium and chromium ions. The modified BC membrane exhibits superior filtration performance and water permeability than pristine-BC. The targeted metal ions were rejected more than 90% from the effluent. The modified membranes demonstrated a flux recovery of above 90% maintaining its effectiveness even after five successive cleaning-filtration cycles. [ABSTRACT FROM AUTHOR]

• The development and principle of EK-PRB and energy consumption calculations are described. • The enhancement strategies of EK-PRB by regulating key factors are summarized in depth. • The optimization methods of EK-PRB energy consumption are firstly summarized. • The perspectives regarding to main bottlenecks of EK-PRB are comprehensively provided. In the past two decades, electrokinetic technology combined with permeable reactive barriers (EK-PRBs) has demonstrated great potential for soil heavy metal remediation. This review focuses on outlining the strategies for improving the removal efficiency of heavy metal by EK-PRB. The type of electrolyte, electrode material, type and position of PRB material, magnitude of the electric field, soil water content and pH are the key factors. We have summarized and concluded the optimization methods of EK-PRB energy consumption for the first time. We found that regulating the electric field and self-powered cells have great potential for energy consumption optimization in the future. The existing EK-PRB remediation technologies were summarized and prospected, providing a comprehensive and systematic knowledge framework for EK-PRB remediation of soil heavy metal pollution. EK-PRB technology still needs to be explored in the direction of optimizing energy consumption and PRB material development, and more basic research is still needed to collect data for predictive system design. This review would suggest valuable views for practical remediation of heavy metals in soil by EK-PRB with high efficiency and acceptable energy consumption. [ABSTRACT FROM AUTHOR]

[Display omitted] • Summarized the microbial-mediated detoxification pathways of Cr(VI). • Microbial-mediated detoxification mechanism of Cr(VI) have been included. • Current problems and bottlenecks in the field were discussed. • Prospects for chromium pollution treatment and future research perspectives. Chromium, a ubiquitous heavy metal, finds extensive utilization in industrial sectors such as tanning, electroplating, stainless steel production, paints, and fertilizers. Due to its apparent biological toxicity, Cr(Ⅵ) is recognized as a predominant contaminant, inflicting severe impacts on both the environment and biological systems. The remediation of Cr(Ⅵ) serves not only to alleviate its ecological ramifications but also to engender substantial economic savings. Nevertheless, extant physicochemical techniques employed for Cr(Ⅵ) elimination are marred by environmental unfriendliness and reliant on copious chemical agents. In contrast, microorganisms, acclaimed for its cost-effectiveness, good environmental compatibility, and conspicuous removal efficacy, stands as an efficacious and practicable approach for Cr(Ⅵ) pollution mitigation. The operation mechanisms of this strategy encompass microbial adsorption and reduction, etc., facilitating a considerable reduction in hexavalent chromium content. This comprehensive review meticulously delineates the physicochemical attributes and origins of Cr(Ⅵ), alongside its implications for the ecological milieu. Moreover, it accentuates the adsorption and reduction mechanisms pertinent to microbial Cr(Ⅵ) abatement, elucidating the influence of environmental factors and external agents on removal efficacy. Ultimately, considering the non-renewable nature of chromium as a resource and combining with the current research status, some future research prospects are proposed, offering forward-looking perspectives for future research endeavors. [ABSTRACT FROM AUTHOR]

[Display omitted] • Heavy metals binding behaviors of sewage sludge DOM components were explored. • The sewage sludge DOM components can bind with Zn, Cu and Cr, rather than Pb. • Sewage sludge humic-like components can be used to modify heavy metal-polluted soil. • "Treating the contaminations with wastes" strategy was formed for pollution control. Dissolved organic matter (DOM), known for its ability to influence the environmental geochemical behavior of heavy metals, is widely regarded as an eco-friendly substance for mitigating heavy metal pollution in the environment. Understanding the unique properties of DOM as a ligand is essential for comprehending its impact on the migration and toxicity of metal pollutants. In this study, sewage sludge composting DOM components were used as ligands for the biding of heavy metal contaminants. Parallel factor analysis (PARAFAC) and variance partitioning analysis (VPA) was employed to analyze the complexing properties. Four DOM components were found in sewage sludge composting products. The identified DOM components in sewage sludge showed significant complexing ability with Zn, Cu and Cr, rather than Pb. Furthermore, based on VPA analysis, the heavy metal contaminants-binding contribution scores of each DOM components showed that simple structure DOM component C1 showed high Zn, Cu and Cr-binding ability. However, high humification degree DOM components presented high stability which could be employed for long-term heavy metals contaminants control. These promising findings provide valuable insights into the distinct binding properties of various DOM components with contaminants. This characterization serves as a theoretical foundation to support efforts in heavy metals control. [ABSTRACT FROM AUTHOR]

[Display omitted] • A total of 9 HMR-MDRBs and 16 associated genes were identified from wastewater. • Microbubble UAPR adapted blue light successfully controlled HMR-MDRB and HMRGs-ARGs-MGE. • DO and blue light have significant effects on HMRG and MGE reduction. • Stable DO supplementation was a critical factor in controlling the type of ROS. • 1O 2 contributed to ARGs and integron reduction; h+ reduced pbrT and transposon. The emergence of multidrug resistance (MDR) and heavy metal resistance (HMR) in bacterial pathogens and genes through mobile genetic elements (MGEs) from wastewater effluents needs to be eradicated using green technology. HMR is critical to controlling antimicrobial resistance but has been neglected in most photocatalytic disinfection (PCD) studies. Advanced photocatalysis in antimicrobial studies requires a strategic approach to enhance the disinfection efficiency. This study applied an optimized upflow airlift photocatalytic reactor (UAPR) with microbubble air and blue light to remove the antimicrobial resistance (HMR–MDR bacteria (HMR–MDRB), HMR genes (HMRGs), antibiotic resistant genes (ARGs) and MGEs) and inhibit pathogenicity in a mixed culture of high-strength HMR–MDRB isolated from wastewater. Stable dissolved oxygen (DO) supplementation and blue light significantly affected the HMRGs and MGE reduction, resulting in enhanced disinfection activity (30 %) and reaction time (60 min) required for the complete inactivation of HMR-MDRB mixed culture. The process effectively reduced the bla NDM-1 (3.37 log), pbrT (2.18 log), intl1 (2.16 log), and tn916/1545 (4.07 log), with a PCD rate constant (k g) of 0.0515 min−1, 0.0359 min−1, 0.0292 min−1, and 0.0662 min−1, respectively. Process mechanism studies showed that the stable supplementation of DO was a critical factor in controlling the type of reactive oxygen species (ROS), resulting in type II ROS, 1O 2 , as the critical free radical contributing to the reduction of ARGs and integron, whereas h+ was the ROS for pbrT and transposon. [ABSTRACT FROM AUTHOR]

[Display omitted] • Efficient removal of thallium by MnO 2 @HKUST-1 catalyst. • Conformation of thallium removal kinetics to the Arrhenius law. • Electrolysis-based recovery of thallium from the washing solution. With the rapid development of ore refining, coal power plants, and mining, aqueous thallium pollution in natural waters has been reported over the past few decades. However, few thallium control technologies have been put into practice. In this study, a modified MOF adsorbent, MnO 2 @HKUST-1(MOH), was fabricated. Its chemical component shift, thermal stability, and microstructure changes during thallium adsorption were analyzed using TGA, XRD, XPS, and TEM-EDS techniques. The results showed a promising Tl+ removal rate of over 90 %, and an adsorption capacity of 178.8 mg/g was obtained at a pH of 5 and a temperature of 293 K. The dynamic behavior of Tl+ adsorption on MOH was simulated using power rate law expression (PRL), pseudo-first-order model (PFO), and pseudo-second-order model (PSO), which revealed a superior selection of Tl+ among other competing heavy metal ions (Cr3+, Fe3+, Ca2+, Zn2+, and Cu2+). The Tl+ removal mechanism was further studied, which was mainly forced by surface adsorption/desorption. Based on its efficient Tl+ removal rate, high adsorption capacity, promising regeneration property, and economical price, the MOH adsorbent has the potential to be a feasible option for smelting, ore refining, packaging, and testing wastewater treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel and greener approach is used to develop TFC/TFN membranes. • GO-NH-NH 2 is used as nanofillers to enhance the TFN membrane's properties. • Rejection of Na 2 SO 4 (∼96 %), Pb(NO 3) 2 (∼95 %), CuSO 4 (∼94 %) and CdSO 4 (∼92 %) salts. • TFN membranes showed enhanced antifouling properties and antibacterial performance. Alternate to the conventional dip coating method, a new eco-friendly approach has been used to develop thin-film nanocomposite (TFN) membranes in this research work, all while preserving the exceptional separation capabilities of TFN membranes. The methodology is altered by employing spray coating and implementing vapor-phase interfacial polymerization (VP-IP) to craft thin-film nanocomposite membranes. This innovative approach significantly reduces reagent consumption and eliminates the need for organic solvent (n -hexane). By incorporating amine-functionalized graphene oxide (GO-NH-NH 2) as a nanofiller, we have fabricated both thin-film nanocomposite (TFN) and thin-film composite (TFC, without nanofiller) membranes. Developed membranes were characterized with various physicochemical characterization techniques and tested against heavy metal ions. The membranes demonstrated outstanding performance, with ∼ 96 % rejection of Na 2 SO 4 , ∼95 % rejection of Pb(NO 3) 2 , ∼94 % rejection of CuSO 4 , and ∼ 92 % rejection of CdSO 4 salt with highest pure water flux 46.57 Lm2h−1. The antifouling characteristics and antibacterial activity of the membrane were also assessed, revealing that including nanosheets has substantially elevated the antifouling properties, notably by increasing the flux recovery ratio. Furthermore, the prepared membranes exhibited enhanced antibacterial performance after incorporating these nanosheets. [ABSTRACT FROM AUTHOR]

[Display omitted] • Protein-like substances contributed a lot to heavy metals removal in CWs. • Pyrite oxidation facilitated TP removal via the complexation of ferric hydroxide. • Biochar and pyrite promoted heterotrophic and autotrophic denitrification in CWs. • Functional bacteria related to autotrophic denitrification were enriched by pyrite. Wastewater polluted by heavy metals with low C/N ratio posed a big challenge to constructed wetlands (CWs) for sustainable advanced wastewater purification. In this study, biochar coupled with pyrite was successfully applied in CWs to simultaneously remove organics, total nitrogen (TN), total phosphorus (TP) and heavy metals, with the highest removal efficiency of 95.78%, 98.78%, 96.22% and 99.91%, respectively. Batch tests proved that the complexation of ferric hydroxide from pyrite oxidation played an important role in TP and heavy metals removal. Meanwhile, fluorescence excitation-emission matrix combined with parallel factor analysis (EEM-PARAFAC) further manifested that protein-like substances contributed a lot to heavy metals stabilization. Moreover, the multiplication of Proteobacteria , Chloroflexi at phylum level and Dechloromonas at genus level, which were capable of heterotrophic or autotrophic nitrate reducing process indicated that the denitrification capacity of CWs was significantly enhanced by biochar and pyrite. This study provided a feasible insight into the application of CWs with biochar and pyrite addition to enhance the treatment of low C/N wastewater. [ABSTRACT FROM AUTHOR]

[Display omitted] • Bio-S0 was a more efficient substrate than Chem-S0 in S0Disp process. • Hydrophilic property of Bio-S0 likely facilitated S0Disp process initiation. • Lower crystallinity and presence of -S x - in Bio-S0 likely promote the S0Disp rate. • Sulfur disproportionating bacteria was more enriched in Bio-S0 driven S0Disp system. Sulfidogensis via element sulfur disproportionation (S0Disp) has been recently suggested to be a cost-effective and low carbon footprint process to produce sulfide for wastewater treatment such as denitrification and the removal of heavy metals. However, studies on this process are limited in using the industrial grade chemical sulfur (Chem-S0). In this study, biogenic sulfur (Bio-S0), a solid waste produced from biogas bio-desulfurization, was investigated for the first time in the S0Disp process with the performance compared to the Chem-S0 with identical size. The results showed that the S0Disp process driven by Bio-S0 was initiated more rapidly than that by the Chem-S0 (8 d vs 13 d) and performed a 1.2-fold higher sulfide production rate in the steady phase. A series of characterizations were conducted to elucidate the difference between using these two types of S0 in disproportionation. The faster initiation of Bio-S0 sets was suggested to correlate its hydrophilic properties, while the higher sulfide production rate was likely due to its higher reactivity as indicated by the lower crystallinity and the presence of organic polysulfane with lower dissociation energy for the S-S bond. Additional tests demonstrated that the Bio-S0 could be more readily attacked by the sulfide to produce polysulfide, a putative rate-limiting step of S0 taken by bacteria in the S0Disp process. Moreover, the sulfur-disproportionating bacteria were found to be enriched more in the Bio-S0 set, which might also contribute to the higher sulfide production rate. This study extended the knowledge of Bio-S0 in good bioavailability and offered new opportunities for reusing this solid waste. [ABSTRACT FROM AUTHOR]

[Display omitted] • Composts addition (30 %, 50 %, 80 %) could all remediate the mine tailing soils. • 50 % Composts was the optimal to reduce aqueous heavy metal(loid)s by 82.9 ∼ 91.4 % • Enhanced complexation with humus contributed to reduced heavy metal(loid)s mobility. • Improved archaeal diversity and enriched Bacillaceaea benefited Cd mobility reduction. • Excessive addition of Composts from 50 % to 80 % brought rebounded metal pollution. The sludge stabilization products (hereinafter referred to "Composts") added in different addition ratios (30 %, 50 % and 80 %) were applied to remediate the heavy metal(loid)s-contaminated mine tailings. Physicochemical, biochemical and microbial characteristics at day 0 and 180 were systematically investigated. The Composts added in different ratios could all remediate the mine tailings in terms of significantly decreased bulk density, increased organic matters, porosity, germination index, pH and DHA activity, as well as obviously declined aqueous extractable Cu, Pb, As, Cd, Hg, Cr, Zn and Ni (p < 0.05). Taken phytotoxicity alleviation and metal (loid)s mobility inhibition into consideration, the 50 % Composts was the most recommended in this study, with the highest reduction (82.9 %∼91.4 %) in aqueous heavy metal (loid)s concentration comparted to the un-amended. The transformation of Cu, Pb, As, Cd and Hg from exchangeable to more stable forms (especially organically-bound form), due to their enhanced complexation with humus through promoted organic matters aromatization, was considered to drive the alleviation of their leaching pollution in mine tailing soil. While the declined aqueous extractable Cr, Zn and Ni were more likely ascribed to the increased pH value. Further, different from fungal communities not sensitive during remediation, the highest porosity and DHA activity by the 50 % Composts amendment benefited the improved archaeal diversity and enriched bacterial family Bacillaceae (capable of heavy metals biomineralization), further significantly (p < 0.05) contributing to the decrease in Cd mobility. Overall, this study highlights the effective role of the Composts in alleviating heavy metal(loid)s pollution in mine tailings and further clarifies the multiple mechanisms including immobilization, pH adjusting and microbial effects. [ABSTRACT FROM AUTHOR]

[Display omitted] • Stability of biochar to Cd, Zn and Pb in soil enhanced after KMnO 4 modification. • Biotoxicity of metals was reduced by 28%-95% at 10% KMnO 4 -modified biochar dose. • Biochar was oxidized and C-O stretching change was prior during freeze–thaw cycles. • Ion exchange and precipitation were mechanisms for MBC to stabilize Cd, Zn and Pb. • KMnO 4 -modified biochar resisted the adverse effects of freeze–thaw cycles in soil. Biochar has been widely used in soil remediation because of its porosity and impressive efficiency. Many studies have demonstrated the good affinity of biochar for heavy metals (HMs), but efficient modification methods to increase the stability of multiple HMs are lacking. Moreover, few studies focus on biochar's potential ability to ageing resistance and changes in its physicochemical properties during freeze–thaw (F/T) cycles. Here, KMnO 4 -modification biochar (MBC) was prepared and the immobilization and anti-freeze performance of MBC on Cd, Zn and Pb in soil were investigated. The addition of 10 % MBC decreased concentrations of toxicity characteristic leaching procedure (TCLP) by 66.80 %, 25.39 % and 99.68 % for Cd, Zn and Pb, respectively, after 28 days, accompanied by a significant decrease in the phytoavailability and bioaccessibility of HMs in soil. Soil fertility was also improved by MBC application. Furthermore, frequent F/T cycles obviously induced the fragmentation of soil particles and enhanced the activity of HMs. Conversely, MBC particles became finer, accompanied by further oxidation and higher alkalinity but degraded pore structures during F/T cycles. The oxidation of lignocellulose and changes in C-O stretching were greatest among all functional groups in biochar. Therefore, MBC could suppress the migration of HMs through precipitation, cohesion of soil particles, and stronger complexation by oxygen-containing functional groups. Moreover, fractions of HMs were also transferred from exchangeable to potentially labile or nonlabile species. Overall, MBC displayed advantages in the stabilization of HMs and showed higher resistance to F/T cycles and promise for long-term remediation of HM-contaminated soils in cold regions. [ABSTRACT FROM AUTHOR]

[Display omitted] • A new polyacrylate-coated ferrous sulfide and layered double hydroxide was designed. • A high synergistic removal of Cr(VI) with Cu(II), Ni(II), or Cd(II) was achieved. • The reusability of the composite was enhanced when Cr(VI) and Cu(II) coexisted. • Synergistic removal mechanisms of heavy metal oxoanions and cations were proposed. Heavy metal oxoanions and cations often co-exist in the environment and it is a critical challenge to achieve their simultaneous and efficient removal due to their presence of opposite charges. Here, a polyacrylate-coated ferrous sulfide and layered double hydroxide (PAA/FeS@LDH) nanocomposite was developed. Results illustrated that PAA/FeS@LDH exhibited excellent reductivity and stability due to the dispersion of PAA and the support by LDH. The removal efficiency of single Cr(VI) (9.73 mg/L) using PAA/FeS@LDH reached 100 % within 120 min, which was significantly higher than that of LDH (35.39 %), FeS (73.13 %), and FeS/LDH (96.47 %). Attractively, an enhanced removal of Cr(VI) (19.46 mg/L) by PAA/FeS@LDH in the presence of Cu(II), Ni(II), or Cd(II) was observed, with Cr(VI) removal efficiency increasing from 49.63 % (single Cr(VI)) to 99.51 %, 82.46 %, and 72.18 % within 30 min, respectively. The adsorption capacities of Cr(VI) significantly enlarged from 140 mg Cr/g (single Cr(VI)) to 221, 175, and 171 mg Cr/g when co-existing with Cu(II), Ni(II), or Cd(II), respectively. Another interesting outcome was the significant enhancement of reusability of PAA/FeS@LDH by the co-existence of Cr(VI) and Cu(II). After 5 cycles, PAA/FeS@LDH could still remove 96.97 % of Cr(VI) together with >70 % of Cu(II) in the mixed solution, by contrast, the removal efficiency of Cr(VI) was only 38.04 % in a single solution. The characterization analysis and density functional theory calculations demonstrated that besides surface reduction, complexation and precipitation, the cation-anion bridge interaction was an essential mechanism of achieving the synergistic removal of heavy metal oxoanions and cations. [ABSTRACT FROM AUTHOR]

[Display omitted] • Unique properties of hydrogel beads, i.e. stimuli-responsive properties and smart adsorption behaviors. • Advanced techniques for preparation of hydrogel beads are summarized and compared. • Different natural and synthetic polymers for preparation of hydrogel beads. • Adsorption mechanisms of hydrogel beads for pollutants in aqueous solutions. • Recent advances of hydrogel beads in the adsorption and removal of various contaminants. Hydrogel particles, encompassing spherical beads (microgels) and non-spherical particles (pears, cylindrical, or irregular shapes), show outstanding features including biocompatibility, good mechanical properties, tunable sizes ranging from micrometer to tens of nanometers, and large active surface areas. They also offer simplicity in design and operation, excellent regeneration capabilities, and non-generation of secondary contaminants. As a result, they are widely recognized as exceptional adsorbents and are extensively utilized in separating and purifying various contaminants in water and wastewater. Understanding the unique properties, preparation techniques, and innovations of hydrogel particles plays a vital role in the formulation of development strategies of novel hydrogel adsorbents towards sustainable purification of contaminants in aqueous solutions. Here, we provide a critical review of the interesting characteristics of hydrogel particles and several types of polymers for their design and fabrication. The state-of-the art applications, innovations, important adsorption mechanisms of hydrogel particles in the removal of various pollutants are also summarized and discussed. The advantages/disadvantages of different biopolymers and synthetic polymers, and advanced technologies for preparation of hydrogel particles are emphasized as well. This review aims to consolidate scientific evidence to facilitate the development of novel adsorbents based on hydrogel particles for water and wastewater treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • Specially modified coffee grounds adsorbents were developed to capture Cd2+ from wastewater. • Cd2+ was reduced and deposited on the surface of activated carbon under the action of sulfoxide from the modified adsorbent. • The adsorption capacity of adsorbent was greatly enhanced after reducing H+ interference. Cadmium ions (Cd2+), due to their high toxicity, easy migration and recalcitrant degradation, pose a high risk to both ecological security and human health. Various biosorbents have been developed to eliminate Cd2+ from contaminated environmental media. However, the mechanism involved is mainly coordination, in which the large amount of H+ generated is unfavorable for Cd2+ removal, resulting in a poor adsorption capacity. Here, coffee grounds were prepared by calcining into functional biochar modified by phosphoric acid and mercaptoacetic acid (PAC-SH) as a high-performance absorbent for the removal of Cd2+ from contaminated water. PAC-SH-140 possesses a three-dimensional (3D) microporous structure and large specific surface area (781 m2/g). The adsorption capacity of PAC-SH-140 for Cd2+ was 205 mg/g, which is 2.7 times higher than that of PAC (75 mg/g). Besides complexation, cation-π coordination and electrostatic interaction, Cd2+ was also reduced to Cd0 under the action of sulfoxide. The adsorption capacity of PAC-SH-140 was improved via these multi-pathway mechanisms. For the first time, the interference of H+ in the adsorption process was weakened, thereby enhancing the adsorption behavior. The adsorption capacity achieved a significant breakthrough (328 mg/g, up by 60 %), providing new guidance for the industrial application of heavy metal adsorption. These findings may offer a promising strategy for low-cost and friendly remediation of Cd2+ contaminated media. [ABSTRACT FROM AUTHOR]

• Efficient two-step phase transition extracted valuable metals from gypsum. • Path-0.5 outpaced path-0, achieving 99.9 % Cr and 98.8 % Cd extraction. • Atom rearrangement in two-step transition triggered atom remove form the lattice. • Extraction efficiencies for trace Pb, Zn, Hg, and As were > 98.5 %, and 95.6 % for Sr. Retrieving valuable metals (VMs) from industrial waste is an attractive approach to reduce the continuous consumption of metallic resources and prevent the environmental contamination by heavy metals. However, metal extraction efficiencies are extremely low due to their entrapment in crystal lattices. Herein, a universal strategy for extracting VMs from gypsum (CaSO 4 ·2H 2 O), a common industrial waste, was reported using a two-step phase transition of dehydration–rehydration; metal extraction was achieved by designing an appropriate phase transition route and controlling the phase transformation kinetics. As the phase transition route to CaSO 4 ·0.5H 2 O (path-0.5) proceeded faster than that to CaSO 4 (path-0), higher extraction efficiencies were realized for Cr (99.9%) and Cd (98.8%) from gypsum. Mechanistic investigations indicated that during the selected path-0.5 dehydration, water molecule loss from gypsum initiated a direct solid-state transformation, triggering the first rearrangement of local atoms and excluding partially incorporated metals from the CaSO 4 ·0.5H 2 O lattice. The subsequent rehydration from CaSO 4 ·0.5H 2 O to CaSO 4 ·2H 2 O, with a phase transition rate faster than that of path-0, triggered the secondary atom rearrangement. The synergism between the two atomic rearrangements finally led to the complete release of trapped metals. Additionally, this strategy was used for retrieving other metals (e.g., Pb, Zn, Hg, As, and Sr) from gypsum, thereby potentially offering a new approach for designing an appropriate phase transition route for extracting VMs from other hydrous minerals. [ABSTRACT FROM AUTHOR]

[Display omitted] • Surface soil can efficiently activate PMS without any extra energy or catalyst. • Free Fe oxides in soil play a vital role in PMS activation for BPA removal. • The process is almost not inhibited by common substances, except for SOM. • The soil properties before and after PMS treatment have altered insignificantly. • BPA-contaminated soil toxicity displays considerable reduction by PMS treatment. Peroxymonosulfate (PMS) has been extensively applied in soil refractory organics remediation, but studies without an activator were scarce. Besides, the role of soil as well as the interaction between the soil constituents and PMS remained unclear. Using bisphenol A (BPA) as a model contaminant, our findings demonstrated that soil could efficiently activate PMS for BPA abatement in water and slurry. Free Fe oxides, especially crystalline Fe oxides in soil, were primarily responsible for PMS activation through nonradical pathways (singlet oxygen) for BPA removal, but soil organic matter (SOM) might inhibit the process. Moreover, BPA elimination was almost not inhibited by the addition of anions (Cl−, NO 3 −, HCO 3 −, and SO 4 2−) and humic acid, but could be promoted by cations (Fe3+ and Mn2+). PMS oxidation caused an insignificant impact on the bioavailability of heavy metals, except for Fe, Mn, SOM, pH, total phosphorus (TP) content, soil composition, and crystal structure have not changed obviously after PMS treatment. BPA decomposition pathways were proposed based on the intermediates identified. Furthermore, the phytotoxicity of BPA − polluted soil was significantly reduced after PMS remediation in terms of crop growth indexes. Overall, the study provided new insights into the crucial role of soil constituents in PMS activation and inspired more energy or catalyst − saving soil remediation strategies. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel Fe3+-modified magnetic chitosan (MCS-Fe3+) was facilely fabricated. • Cooperation of multi-mechanisms enables TC's adsorption equilibrium within 15 min. • At near neutral condition, Cu2+ and TC mutually enhanced each other's removal. • A 'Three-stage' dynamic sorption profile was proposed in TC-Cu2+ binary system. • MCS-Fe3+ was suitable for simultaneously and synergistically removing TC and Cu2+. Some trace heavy metals, used as feed additives to promote animal's growth, often coexist with antibiotics in aquaculture wastewater to form combined pollution, inevitably altering their adsorption behavior and mechanism on adsorbent surfaces. Until now, there are still no studies on systematically unravelling dynamic adsorption process of both heavy metals and antibiotics at different sorption stages. Thus, a novel Fe3+-modified magnetic chitosan composite (MCS-Fe3+) was facilely fabricated as a model adsorbent for revealing its co-adsorption behavior and mechanism toward Tetracycline (TC) and Cu2+. It was found that the as-resultant adsorbent displayed extraordinary sorption capability toward TC with q max value of 230.66 mg g−1. The cooperation of multi-mechanisms (e.g. , H-bonding, electrostatic attraction, and Fe3+-complexation) enables TC adsorption to reach equilibrium within 15 min. Interestingly, in TC-Cu2+ binary system, the co-existing Cu2+ or TC dramatically promoted each other's removal efficiency at pH of 6 due to formation of ternary complex (adsorbent-Cu2+-TC or adsorbent-TC-Cu2+). Most importantly, a 'Three-stage' adsorption profile of TC and Cu2+ in their mixed system was firstly proposed and described in details, providing unique insights into adsorption pattern of multi-pollutants in actual wastewater. Moreover, the as-designed composite was applied for treating simulated aquaculture wastewater bearing different ratios of TC and Cu2+ and satisfactory removal rates over 80 % were obtained, confirming its feasibility in simultaneously and cooperatively eliminating TC and Cu2+ in complex wastewater. [ABSTRACT FROM AUTHOR]

[Display omitted] • Aminated silica aerogels were synthesized via self-catalyzing polycondensation. • Aminated silica aerogel affects both the microstructure and adsorption properties. • The optimized aerogel has high mechanical strength and low thermal conductivity. • It has excellent CO 2 adsorption capability of 3.13 mmol/g at a pressure of 15 kPa. • It has notable efficacy and reusability for removing heavy metal ions such as Pb2+. Although aminated silica aerogels have already been identified as potential materials for adsorption, separation, and thermal insulation applications, their extensive use is limited by their natural brittleness and costly production. In this study, aminated silica aerogel monoliths were synthesized via a facile route utilizing 3-aminopropyl triethoxysilane (APTES) acting as both an amination precursor and a self-catalyst as well as tetraethyl orthosilicate (TEOS). The fabricated TA-NH 2 -x (i.e., using an APTES/TEOS molar ratio of x) adsorbents had high CO 2 selectivity, efficient heavy metal removal capability, and good mechanical strength. Remarkably, the TA-NH 2 -2.5 aerogel exhibited a high CO 2 capture capacity (3.10 mmol/g) and CO 2 /N 2 selectivity (9 5 1) under typical flue gas conditions. Moreover, it showed efficient removal of hazardous heavy metal ions such as Pb2+, Hg2+, Ni2+, and Cu2+, as well as excellent mechanical strength (13.96 MPa) and thermal conductivity (29.1 mW/mK). These results suggest that synthesizing aminated aerogel monoliths via self-catalyzed polycondensation using APTES is an efficient strategy for developing rigid multifunctional adsorbents for CO 2 capture and heavy metal removal. [ABSTRACT FROM AUTHOR]

[Display omitted] • Catalysts MC-LDHs recovered from AMD which improved the degradation efficiency. • The adsorbed Mn in LDHs sludge was proved by DFT to be a key activate site. • ROS production pathway was clarified and the catalytic mechanism was proposed. • Norfloxacin degradation in this system was environmental safety. • The heavy metals concentration of catalyst was leached at very low level. Acid mine drainage is rich in metals (including transition metals), so the neutralization treatment based on AMD for in situ regulation will ultimately result in sludge with potential catalytic effects. In this study, we reported a catalyst (MC-LDHs) that differed from traditional catalysts in that it was derived from AMD neutralized sludge containing high concentrations of Mn, which was a typical industrial waste. The catalytic performance of activated PMS for the removal of norfloxacin (NOR, a typical antibiotic) was evaluated under different operating conditions. The contribution of active species in the reaction system was evaluated through quenching experiments, and the types of free radicals were further determined through electron spin resonance experiments. In addition, density functional theory was used to simulate the electron transfer and vulnerable sites of NOR in the adsorption of PMS by MC-LDHs. Subsequently, the degradation pathway of NOR was inferred based on DFT results, and the toxicity changes of intermediate products were predicted. This study has reduced the cost of catalysts and simplified the preparation process of doped catalysts, thus providing a new strategy for catalyst preparation, which is of great significance for the promotion and application of advanced oxidation process. [ABSTRACT FROM AUTHOR]

[Display omitted] • Designing a crosslinking strategy for tailoring high-value agricultural residues. • A type of amphoteric agricultural residues-based porous adsorbent was tailored. • The adsorbent possessed abundant amphoteric sites and developed micropore. • The adsorbent could completely remove multiple heavy metal ions within 10 min. • The adsorbents can be applied in groundwater and soil remediation. Converting agricultural residues into environmentally friendly adsorbents to address the problem of low removal efficiency of low-concentration heavy metal ions is an effective strategy for high-value utilization of agricultural residues. Herein, a simple general strategy is proposed for constructing amphoteric agricultural residues-based porous adsorbents by forming anisotropic cross-linked structures at the heterogeneous interface of agricultural residue, coconut shell carbon, and polyethyleneimine. This green preparation strategy can be widely adapted to agricultural residues with hydroxyl structures, such as bagasse fiber, corn cob, and peanut shell, to prepare high-performance adsorbents with high densities of amphoteric adsorption sites (The density of amino and carboxyl groups was 3.44 mmol·g−1 and 3.64 mmol·g−1) while maintaining a developed microporous structure (BET specific surface area of 760.68 m2·g−1), the reactant conversion rate was higher than 99 %. Interestingly, the synergistic effect of abundant amphoteric functional groups and developed microporous structures enabled the adsorbents to completely remove Cr(VI), Cu(II), Pb(II), and Cd(II) from water within 10 min, which exhibited a promising synchronous removal efficiency for multiple heavy metal ions. It provides a reference for the remediation of heavy metals contaminated groundwater and soil by agricultural residues-based adsorbent. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel PANI@PCDP media targeting both metals and organic micropollutants was developed. • Cr(VI) could be reduced to Cr(III) after being absorbed onto PANI@PCDP at pH 6. • The PANI@PCDP achieved the efficient removal of total Cr through the sequestration of Cr(III). • A broader range of emerging organic micropollutants can be removed using PANI@PCDP. • The PANI@PCDP maintained a high level of performance in surface water and wastewater. The occurrence of diverse pollutants in water resources across the globe, including organic micropollutants and heavy metals, has challenged the efficacy of many existing water treatment processes. Various materials and media have been developed for removal of these compounds, but few have the capacity to remove multiple contaminants which are typically present in real water sources. Here we report on a novel sorbent (PANI@PCDP) for the simultaneous removal of organic micropollutants and heavy metals during a single process. Cr(VI) and bisphenol A (BPA) were selected as target pollutants due to their frequent occurrence in aquatic environments and the significant health risks they pose. PANI@PCDP exhibited a high level of performance for removal of BPA and total Cr at pH 6 for initial concentrations of 0.5–100 mg/L for Cr(VI) and 0.228–22.8 mg/L for BPA. Up to 98 % Cr was removed at pH 6 through the adsorption and reduction of Cr(VI), followed by the sequestration of the generated Cr(III). In addition, BPA could be captured by PANI@PCDP at an adsorption rate of 1.4 × 10-1 g mg−1 min−1 as a result of the fast formation of complexes with the media. When the PANI@PCDP media was tested on a wider variety of emerging organic micropollutants (including chlorinated aromatic compounds, simple aromatics, and pharmaceuticals) good removal was observed. Such performance benefits arise from the integration of porous β-cyclodextrin polymers with polyaniline, which provides the PANI@PCDP with multiple binding sites for contaminant removal. In addition, the PANI@PCDP can be regenerated at least five times without loss in performance using a facile procedure, providing evidence for its practical application in water treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • Progress in polymeric nanocomposite membranes for removing heavy metals from water. • Investigations relevant to carbon-based, and clay-based, nanocomposite membranes. • Studies relevant to zeolite-based, and metal oxide-based nanocomposite membranes. • Critical insights into fabrication strategies for nanocomposite membranes. • The current challenges and future perspectives for nanocomposite membranes. The presence of toxic heavy metals (HMs) in water systems poses significant threats to both human health and the environment. Researchers worldwide have been actively exploring various technologies for HMs removal, and nanomaterial-based adsorption has emerged as a particularly promising approach. Nanomaterials like carbon nanotubes, graphene oxide, zeolites, and metal oxide nanoparticles have garnered attention due to their exceptional adsorption performance, which can be attributed to their high thermal/chemical stability, large surface area, and functional groups. However, the practical implementation of these nanomaterials faces challenges, i.e., recovering the adsorbents and the tendency of aggregation into larger particles. In recent years, the development of polymeric nanocomposite membranes has shown great potential for HMs removal. By incorporating nanomaterials into the polymer matrix, these membranes achieve a synergistic effect of filtration and adsorption, making them highly effective in removing HMs. This comprehensive review focuses on the latest findings regarding the performance of widely studied polymeric nanocomposite membranes. Specifically, it covers carbon-based, clay-based, zeolite-based, and metal/metal oxide-based nanocomposite membranes, discussing their HMs rejection rates, flux rates, and critical insights into fabrication strategies. Furthermore, the review addresses the current challenges and offers future perspectives for nanocomposite membranes. The aim of this review is to provide a comprehensive analysis of the recent advancements in polymeric nanocomposite membrane-based filtration for removing HMs from water. By presenting a detailed overview of the current state of research, limitations, and potential directions, this review serves as a valuable resource for researchers and practitioners in the field. It offers insights into the efficacy of these membranes and paves the way for further exploration in addressing the pressing issue of toxic metal contamination in water sources. [ABSTRACT FROM AUTHOR]

[Display omitted] • Acid modification reduced HMs and extractable PAHs content the most effectively. • H 2 O 2 reduced extractable and bioavailable PAHs but was less effective than acid. • Base treatment significantly increased the extractable PAHs in most BCs. • Porosity and DOC determined contaminant changes in BC after H 2 O 2 or base treatment. The effect of biochars (BCs) chemical modifications on the content of various contaminants is poorly studied and understood, despite the fact that such results would be important in terms of estimating the safety of BCs application. The aim of this study was to evaluate the content of different types of contaminants - heavy metals (HMs), polycyclic aromatic hydrocarbons (solvent extractable - C tot and freely dissolved - C free PAHs) and environmentally persistent free radicals (EPFRs) in post-pyrolytic chemically modified (HNO 3 , KOH and H 2 O 2) BCs produced under diverse conditions (temperature and carrier gas) and from various feedstocks (willow, rice husk, sewage sludge, oil seed rape straw, wheat straw). The physio-chemical properties of BCs were determined (such as morphology, elemental composition and chemical state, and crystalline structure) and correlated with contaminants content. Regardless of the BCs type, acid modification reduced HMs and C tot PAHs the most effectively but simultaneously increased C free PAHs and EPFRs content (compared to pristine BCs). Changes in contaminant content after H 2 O 2 and alkali treatment were more varied and strictly related to the physio-chemical properties of BCs (such as porosity, DOC, and polarity). H 2 O 2 treatment reduced C tot and C free PAHs content but was less effective than acid modification. In contrast, KOH treatment significantly increased the C tot in most BCs, which depends mainly on porosity and DOC changes. Also, the reduction in HMs content and increase in EPFR after alkali and H 2 O 2 treatment were less substantial and more differentiated by BC origin than after acid modification. [ABSTRACT FROM AUTHOR]

[Display omitted] • FeCl 3 -assisted electrokinetic technique coupling hydrothermal carbonization was proposed. • Electrokinetic technique improved P availability by transferring metal oxides to Fe/Al-bound P. • Low pH value of sludge caused by electrokinetic technique favored P transformation and HM removal. • 56–64% of Ni, Cu, and Zn in hydrochars were removed by coupling treatment. • Coupling treatments showed synergistic effects on P reclamation and HM removal. Hydrothermal carbonization is a promising treatment technology for wet organic solid wastes, due to its energy-efficient production of functionalized carbonaceous materials. However, the usage of sewage sludge (SS) derived hydrochar as phosphorus (P) fertilizer for agricultural soil is inhibited by the presence of heavy metals (HMs). Appropriate HM removal technology is required prior to its land application. In this study, an innovative FeCl 3 -assisted electrokinetic technique coupling with hydrothermal carbonization (FEK–HTC) is proposed to produce SS hydrochars with reduced HM content and increased P-retention. FEK–HTC treatment showed synergistic effects in terms of P retention and HM content reduction (56–64 % for Ni, Cu, and Zn). Furthermore, the toxicity of the remaining HMs was dramatically reduced, e.g., by 39.35 % in the case of Zn. Additionally, FEK–HTC transformed P species in hydrochars into highly bio-available form. Electrokinetic treatment resulted in decreased pH values of SS feedstock and promoted the solubilization and erosion of Ca-associated P, resulting in higher non-apatite inorganic phosphorus contents (12.47 to 23.19 mg·g−1) compared to hydrochars from untreated sludge. The P migration patterns during the FEK-HTC treatment were assessed based on the combined result of chemical extraction, 31P NMR, X-ray absorption near edge structure (XANES), and diffusive gradients in thin film (DGT). DGT analysis showed that the addition of treated hydrochars greatly increased the available P content in the soil. The results provide new insights into applying FEK-HTC technique for SS management. [ABSTRACT FROM AUTHOR]

[Display omitted] • Single/multi-step effluent treatment with BPS at supercritical conditions was performed. • HMs were recovered as NCH with BPS, with co-generation of H 2 -rich gas mixture. • The synergetic effect of HMs in wastewater catalyzes the gaseous yield during SCWG. • The synthesized NCH was employed for making carbon-based electrodes for lithium-sulfur batteries. Supercritical water gasification (SCWG) is an effective technique for the conversion of biomass into hydrogen-rich fuel gas. This work addresses two important aspects of the SCWG process by employing the concept of waste to wealth: first, the requirement of heterogeneous catalysts for better efficiency, and second, the safe disposal of byproducts of the process. Metal-contaminated aqueous effluent (Zn-EPW) is used as the reaction medium with the catalyst for single-step hydrothermal conversion of banana pseudo-stem (BPS) to synthesize multi-dimensional value-added products such as H 2 -rich fuel gas, nano metal–carbon hybrids (NCH), and treated aqueous phase. This study demonstrates the enhanced conversion of biomass into hydrogen-rich gas and recovery of heavy metals (HMs) in the form of nanometal carbon hybrids, which can be utilized to fabricate carbon-based electrodes in Li-S batteries. A comparative study of feedstock, such as a combination of Zn-EPW adsorbed on BPS (MA-BPS) with Millipore water, direct treatment Zn-EPW with BPS, and Millipore water with BPS (without HMs), was performed. The results inferred the catalytic effect of heavy metals increased the yield of hydrogen about ∼2.9 times with Zn-EPW and BPS and ∼1.7 times with MA-BPS and Millipore water over the non-catalytic operation. Furthermore, the obtained NCH were characterized to evaluate their performance for electrodes in energy storage devices. The electrochemical performance of NCH obtained after multi-step SCWG of MA-BPS with Millipore water and single-step treatment of Zn-EPW with BPS at 600 °C, have specific capacity of 610 and 615 mAh.g−1 at 0.1C respectively. [ABSTRACT FROM AUTHOR]

• DFT calculation fully supported the results predicted by CD-MUSIC model. • As(V) and Sb(V) exhibited a stronger affinity for bidentate coordination. • P(V) exhibited a stronger affinity for monodentate coordination. • The adsorption competitiveness of As(V) and P(V) was generally stronger than Sb(V). • Ion existing form and coordination structure affinity decided adsorption behavior. Despite the geochemical prominence of As(V), Sb(V), and P(V) coexisting in an extensive array of iron-oxide environments, the comprehension of their mobility and destiny is constrained due to the differences in the surface properties and exposed crystal facets of iron oxides. Herein, goethite primarily exposing the {1 1 0} facet, was employed as the model iron mineral to investigate the competitive adsorption behavior of As(V), Sb(V), and P(V) via batch experiments leveraging EXAFS, CD-MUSIC model, and DFT calculations. Results showed that observed co-adsorption behaviors were attributed to the comprehensive action of goethite surface chemistry, ion existing forms and different coordination structures stability at the molecular scale. CD-MUSIC model indicated As(V) and P(V) competed for surface sites through a combination of bidentate and monodentate coordination, whereas Sb(V) was primarily adsorbed via bidentate coordination, which led to the surpassed competitiveness of As(V) and P(V) on {1 1 0} facet compared to that of Sb(V). The affinity of various coordination structures on {1 1 0} facets based on DFT was found to be consistent with the trends predicted by the CD-MUSIC model. Specifically, As(V) and Sb(V) exhibited a greater affinity for bidentate coordination, while P(V) tended to form monodentate coordination complexes. However, the existing forms of As(V), Sb(V), and P(V) under different pH, especially for protonated species, accelerated the more weakened competitive combination ability of Sb(V) than As(V) and P(V) with increasing pH. Furthermore, charge density difference and Bader analysis have confirmed the contribution of electron transfer from the surface Fe to O towards forming Fe O bonds. This work provided a novel investigation way and facilitated a more profound understanding of the geochemical cycle of toxic metals. [ABSTRACT FROM AUTHOR]

[Display omitted] • As(V) showed a stronger affinity to Fe minerals and inhibited Sb(V) adsorption. • Sb(V) tended to be incorporated into Fe minerals during aging process. • As(V) was mainly adsorbed on the surface of Fe minerals during aging process. • The mobility and bio-availability of As(V) was higher than Sb(V). Iron (oxyhydr)oxides, especially ferrihydrite (Fh), abundant in the natural environment, are frequently applied in controlling the migration of heavy metals like antimony (Sb) and arsenic (As) in contaminated soils. However, little is known about the mobility and fate of Sb and As during the aging of Fh. In this study, we investigated the competitive adsorption between Sb(V) and As(V), the mineralogical transformation of Fh, and the redistribution of Sb(V)/ As(V) during the accelerated aging process of Fh. Our results showed that As(V) inhibited Sb(V) adsorption at the same concentration, but Sb(V) had no discernable influence on As(V) adsorption, suggesting As(V) had a stronger affinity to Fe minerals. XRD patterns showed that Fh was transformed into hematite or goethite in the presence of 25 mg/L Sb(V), but the transformation was inhibited in the presence of 25 mg/L As(V). Regarding the redistribution, the mobility of Sb(V) appeared to decrease probably via incorporation into Fe minerals during aging, and Fe minerals could host at least 20 % (w/w) Sb(V) in the low-mobility pool. As for As(V), the transformation of Fh was impeded resulting in high proportions of As(V) retained in high-mobility pool, with only 1.6 % (w/w) As(V) in the low-mobility pool. Our findings highlighted the differential behaviors of Sb(V) and As(V) during the adsorption and aging process on Fe oxide materials. These insights contributed to a deeper understanding of the mobility and fate of co-existing Sb(V) and As(V) in contaminated soils and offered practical guidance for their remediation using Fe oxide materials. [ABSTRACT FROM AUTHOR]

A novel molecular design paradigm for developing narrowband electroluminescence emitter composed of multiple resonance (MR) framework and organometallic complex is proposed here, and the solution-processed organic light-emitting diode (OLED) employing the target organometallic platinum (II) complex BNCPPt as an efficient dopant emitter exhibits green CIE coordinates (0.22, 0.63) with narrow FWHM (35 nm), and achieves maximum EQE of 13.5% with very low efficiency roll-off (4.4%) at 1000cd/m−2(-|-). [Display omitted] • A novel narrowband organometallic complex EL emitter composed of multiple resonance (MR) framework is developed. • A simple solution-processed fabrication process for preparing high-performance OLED has been achieved. • Quite high maximum EQE >13.5% with very low efficiency roll-off (4.4%) at 1000 cd m−2 has been realized. The narrowband emission required by wide color gamut display is an extremely important research topic for any luminescence mechanism, which has made significant progress in traditional fluorescence and thermally activated delayed fluorescence (TADF) based on purely organic compounds, but is far from mature in organometallic complexes. Herein, we propose a feasible molecular design paradigm for constructing the desirable organic electroluminescence (EL) emitter with narrowband emission by integrating an original multiple resonance TADF (MR-TADF) fragment into the classical platinum (II) complex. The solution-processed organic light-emitting diode (OLED) by employing the target model platinum (II) complex BNCPPt as the dopant emitter shows light green emission with a peak of 507 nm and narrow full-width at half-maximum (FWHM) of 35 nm, which achieves a maximum external quantum efficiency (EQE) of 13.5% with very low efficiency roll-off of 4.4% at 1000 cd m−2. [ABSTRACT FROM AUTHOR]

• Synergetic interactions between ZVI and Sch during premixing process existed. • Premixing time and mass ratio played essential roles in As(III) removal. • Mass and electron transfer occurred between Sch and ZVI during the premixing. • Recrystallization of Sch and the corrosion process of ZVI were accelerated. • As(III) removal capacity of ZVI/Sch mixtures improved by premixing. Although the enhanced removal of heavy metals using zero valent iron (ZVI) assisted by schwertmannite (Sch) was achieved in previous studies, their interactions between Sch and ZVI seems to be bidirectional and impact on the As(III) removal by ZVI/Sch mixture remains elusive. This study investigated As(III) removal in the mixed suspensions of ZVI and Sch with various premixing times and mass ratios. Batch experiments demonstrated that ZVI/Sch mixture with the premixing time of 3 h and mass ratio of 2:1 exhibited excellent performance in As(III) removal. The results indicated that synergetic interactions between ZVI and Sch during premixing process played crucial roles, particularly in terms of morphological variations. Results of FTIR and XPS revealed the mass and electron transfer occurred between Sch and ZVI during the premixing process, resulting in the accelerated recrystallization of Sch and the corrosion process of ZVI. Furthermore, the premixing process was found to significantly improve the As(III) removal capacity of ZVI/Sch mixture without altering the As(III) removal pathway, including the adsorption/precipitation/oxidation processes of ZVI and surface complexation/ion exchange/channels inlay of Sch. These findings shed light on the complex interactions between ZVI and Sch in As(III) removal and offer promising opportunities for the development of efficient treatment strategies in As(III)-contaminated environments. [ABSTRACT FROM AUTHOR]

[Display omitted] • A simple strategy for polyphenolic nano-microspheres (PTA) by TA crosslinking. • This adsorbent exhibited tunable pH-responsive metal coordination structures. • High selective adsorption with larger K d of 84400 mL/g and 95 % efficient regeneration. • Yielding a high treatment capacity of ∼ 5250 L/kg sorbent for application. The proficient advancement of nanoscale adsorbents assumes a pivotal role in the enhanced elimination of heavy metals to trace concentrations. Nevertheless, within the realm of engineering, the attainment of elevated selectivity and effective regeneration remains an arduous endeavor. In this context, we propose a novel structure-tunable sorption/regeneration mechanism by designing TA cross-linked polyphenolic nano-microspheres (PTA). These PTAs exhibit tunable pH-responsive metal coordination structures, enabling high sequestration and purification in removing heavy metals, and facilitating efficient regeneration. Taking Pb(II) as an example, under neutral conditions, the PTAs form a six-coordination configuration with Pb(II) ions, resulting in larger selectivity of K d : 84400 mL/g with a 99 % removal efficiency even in the presence of various cations, anions, and organic acids. This performance far surpasses that of the commercial ion exchanger D001, exhibiting an enhancement factor of nearly 250 times, rendering it amenable for deployment in a wide array of contaminated water sources, encompassing lake water and industrial wastewater. Notably, the PTA also demonstrates exceptional practical utility, affording a voluminous treatment capacity of 5250 L per kilogram of adsorbent in wastewater scenarios. Furthermore, under acidic conditions, the transformation of PTA's metal coordination into a weaker two-coordination facilitates the efficient desorption of Pb(II) with an impressive efficiency of up to 99.0 % across multiple cycles. In contrast, commercial cheated resins D401 and D418 experience a significant 70 % decrease in reuse performances after the first cycle. This study provides a new perspective and platform for efficient adsorbent development through coordinated structural changes, it holds the potential to alleviate the challenges associated with deep restoration of heavy metal-contaminated wastewater. [ABSTRACT FROM AUTHOR]

[Display omitted] • V(V) reduction and denitrification, coupled with S0 oxidation, were observed. • 96.7 ± 2.2 % and 99.0 ± 1.1 % of V(V) reduction and NH 4 +-N oxidation were accomplished. • V(V) was reduced by MAGs containing genes (narG , napA) or MHCs (OmcB , MtrA). • NH 4 +-N was oxidized to NO 3 –-N/ NO 2 –-N, and then reduced to N 2 or assimilated. • NH 4 +-N oxidation was primarily facilitated by nitrifiers (e.g., Anaeromyxobacter sp.). The extensive use of ammonium (NH 4 +) as a precipitant in non-ferrous metallurgy, such as vanadium production, leads to the co-occurrence of toxic heavy metals and NH 4 +-N in the resultant wastewater. Finding an efficient and cost-effective method for simultaneously removing vanadate [V(V)] and NH 4 +-N in a single step has remained unexplored. This study presents a novel approach by establishing the synchronous bio-elimination of V(V) and NH 4 +-N in a sulfur (S0)-based autotrophic system. Remarkably, 96.7 ± 2.2 % of V(V) and 99.4 ± 0.8 % of NH 4 +-N were successfully removed within 24 hrs. V(V) was transformed into V(IV) precipitates, while S0 was oxidized into sulfate, achieving complete nitrogen removal. Fifty-six genomes were retrieved and constructed from metagenomic binning, unveiling symbiotic interactions involved in sulfur, nitrogen, and vanadium transformation. With the annotation of functional genes (e.g., nar , nir , nap , nor , nos , sox , sor , dsr) and multi-heme c-type cytochromes, it was identified that V(V) reduction and denitrification, coupled with S0 oxidation, were mediated by species such as Sulfuricurvum sp., Achromobacter sp., and Thiomonas sp.. Meanwhile, NH 4 + oxidation was accomplished by Anaeromyxobacter sp.. Furthermore, autotrophs harnessed inorganic carbon through the Calvin-Benson-Bassham and Wood-Ljungdahl pathways to synthesize organic intermediates, which were subsequently consumed by heterotrophic organisms (e.g., Pseudomonas sp.) to facilitate V(V) reduction and denitrification. The quantification of transcripts associated with genes responsible for V and N metabolism provided additional evidence of these metabolic pathways' existence. This study offers a sustainable and environmentally friendly strategy for mitigating the adverse environmental impacts of vanadium production wastewater. [ABSTRACT FROM AUTHOR]

[Display omitted] • A robust polyoxometalate and metal–organic framework hybrid is designed. • The hybrid is a catalytic reservoir for generation of reactive oxygen species. • The hybrid can eradicate bacteria and enhance wound healing efficiently. • Antibacterial mechanism is investigated. Infections by bacteria always post significant challenges to global human health. Recent developed non-antibiotic treatment, such as using metal–organic frameworks (MOFs) to kill bacteria by generating reactive oxygen species (ROS) represents a promising strategy. However, drawbacks including low efficiencies of ROS generation and high concentrations of toxic metal ions released always exist. We have creatively designed a robust polyoxometalate (POM) and MOF hybrid (denoted as CuPOM-MOF@S) that functions as an efficient catalytic reservoir for cascaded generation of ROS (mainly ·OH) from H 2 O 2 thus eradicating bacteria and enhancing wound healing at an administration dosage as low as 5 μg∙mL−1. The remarkable antibacterial capability surpasses those for most MOF-based materials reported thus far, which is mainly attributed to the reservation of massive catalytic copper ions, the synergistic effect regarding catalytic activity between MOFs and Keggin-type POMs as well as its bacteria-capturing ability by the coated surfactants. Its biological safety is investigated and confirmed by cell cytotoxicity and body weight assessment. This work presents a prospective strategy towards cascaded ROS generation by combining inorganic catalytic POMs with MOFs thus for multiple biomedical applications including treating bacterial infections and cancer as well as inducing biological signal responses. [ABSTRACT FROM AUTHOR]

[Display omitted] • OA with 8 carbons provides better adsorption capacity through steric hindrance. • –COOH competes between OA/H 2 bpydc and H 2 bpdc to bind Zr cluster to form defects. • L-cysteine modification introduces more adsorption sites such as –COOH and –SH. • Easy recyclability and separation of aerogel beads were provided. • Adsorption capacity for Pb2+, Cd2+ and Cu2+ increased by 66.2, 10.7 and 5.8 times. Threats caused by heavy metal ions have prompted people to develop porous and functionalized materials to remove them. Metal–organic frameworks (MOFs) show potential for heavy metal ions removal due to the high specific surface area, tunable pore size, flexible designability and favorable stability. However, the intrinsic microporous structure and powder form limit their applications. Herein, we designed a shapeable aerogel bead incorporated with L-cysteine-modified defective UiO-67 for Pb(II), Cd(II) and Cu(II) adsorption. The pristine UiO-67 powders were firstly modified by introducing the modulator (octanoic acid) and an extra ligand (2,2′-bipyridine-5,5′-dicarboxylic acid) to construct defects, both of them competed with the original ligand to coordinate to Zr clusters, resulting in an increased BET surface area (from 337.66 to 1,037.14 m2/g) and mesoporous ratio (from 34 % to 74 %) of the pristine UiO-67. Then, the graft of L-cysteine containing –COOH and –SH introduced more active adsorption sites. Moreover, the powder material was incorporated into sodium alginate aerogel beads which enhanced the recyclability and further improved the adsorption capacity for Pb(II), Cd(II) and Cu(II). These appealing advantages endow the adsorbent with quicker adsorption equilibrium (240 min), and outstanding removal capacities for Pb(II) of 661.2 mg/g, Cd(II) of 296.2 mg/g and Cu(II) of 326.4 mg/g. The chelation and ions exchange between the numerous functional groups including –COOH, –OH and –SH and the heavy metal ions are the main mechanisms for effective adsorption. This work provided a novel approach for the application of MOFs in environmental remediation. [ABSTRACT FROM AUTHOR]

[Display omitted] • New crosslinking agents based on the combination of Calcium and Europium applied on pectin. • Deep structural changes after crosslinking with Eu or Ca + Eu. • Pectin crosslinked with Eu results in a fully amorphous material. • Pectin crosslinked with Ca + Eu results in a semicrystalline material. • Low methoxylation pectin crosslinked with Ca + Eu can remove pharmaceuticals and heavy metals simultaneously. The contamination of water resources by heavy metals and pharmaceuticals is a significant threat to human health and the environment. Pectin is a promising material for removing heavy metals from water. However, its removal efficacy for other types of pollutants is limited. In this study, we developed a novel approach to enhance the remediation capacity of pectin (with a low degree of methylation) by crosslinking it with different agents: calcium, europium, and their combination. We performed scanning electron microscopy, infrared spectroscopy, and X-ray diffraction experiments to understand the molecular structure of pectin after gelation with the three agents. Our results showed that calcium, europium, and their combination all induce the gelation of pectin. However, the reticulated pectin structures exhibited significant structural differences depending on the type of crosslinking agent used, which affected the adsorption capacity. Specifically, calcium cations partially formed a crystalline "egg-box" structure, whereas europium cations produced a more homogeneous network without crystalline regions. The dual-crosslinking system comprising calcium and europium cations resulted in an intermediate network with both crystalline and amorphous regions. Our findings suggest that dual-cross-linked pectin is a highly effective adsorbent for the simultaneous removal of both heavy metals and pharmaceutical products. This novel approach of crosslinking pectin with multiple agents has the potential to significantly enhance its remediation capacity, offering a promising solution for the simultaneous removal of multiple pollutants from water. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synthesis and modification of cross-linked (MIP) for recovery of Pb(II) and As(V). • Analytical techniques were used to characterize and confirm the synthesized material. • Integrative mechanisms for recognition and selective recovery were discussed. • Studying isotherms modeling, kinetics, and thermodynamics parameters of recovery. • Solvent types, interfering ions, selectivity, and regeneration were investigated. A cross-linked molecularly imprinted polymer (MIP) was synthesized and functionalized by metal oxide nanoparticles (TiO 2 and SiO 2) to form a potential cross-linked (MIP) nanocomposite via binding of Nano-TiO 2 and Nano-SiO 2 to cross-linked chitosan. Where chitosan acted as a functional monomer, glutaraldehyde (Glu) acted as an organic cross-linker with bifunctional reactive groups, and lead (II) and arsenic (V) acted as templates. This work is composed of a binary of promising ideas: (a) a facile preparation of cross-inked molecularly imprinted polymer (MIP) via bulk polymerization method, and (b) the functionalization of newly fabricated cross-linked (MIP) using metal oxide nanoparticles. The fabricated cross-linked biopolymer nanocomposite was used for simultaneous and selective recovery of toxic metal ions from water. Microwave irradiation was applied as an assisted technique to estimate the performance of the synthesized material. The properties and structure of the fabricated Nano-TiO 2 @Cross-linked Chitosan@Nano-SiO 2 were characterized by FT-IR, XRD, TG/DTA, BETs, SEM-EDX, TEM, and XPS. The results indicated that Pb(II) at pH 5.0 ± 0.15 and at time varied from 5 sec to 25 sec exhibited recoveries capacity 97.99–99.81% and Q max 81.97 mg/g, while As(V) at pH 4.0 ± 0.15 and at 5 sec to 20 sec, exhibited recoveries capacity 96.38–99.72 % and Q max 625.00 mg/g. The cross-linked MIP nanocomposite exhibited an improved specific surface (388.0 m2/g) and mesopore size (15.18 nm) compared to its precursors. Freundlich and pseudo -second-order equation well-fitted the experimental data. Pb(II) and As(V) recoveries were exothermic, spontaneous, and governed by entropy change. Solvents subjected to eliminate the templates, interfering ions, selectivity, and reusability experiments were carried out. Newly integrative mechanisms for implementing cross-linked (MIP) nanocomposite for recognizing and recovering metal ions were adequately explained. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fabrication of antifouling BGM nanobioaerogel utilizing industrial byproduct. • Statistical optimization based on mechanical stability and adsorption capacity. • High surface area and abundant functional groups in BGM provided stable structure. Fabrication of mechanically stable porous materials with excellent adsorption capacity for different types of heavy metal ions simultaneously is still scientifically and technically challenging. Herein, the Response Surface Methodology (RSM) was employed to statistically fabricate the biological materials (collagen, chitosan) functionalized graphene–magnetite (BGM) hybrid nanobioaerogel. RSM statistically predicted the concentration of GO, Fe2+, collagen–chitosan mixture and glutaraldehyde as 6.78 mg/mL, 0.20 M, 61.39 mg/mL and 68.63 µM, respectively, for the maximum responses of Young's modulus (5.26 kPa) and adsorption capacity. Various spectroscopic and microscopic techniques demonstrated the porous interconnected network structure and superparamagnetic behavior of BGM hybrid nanobioaerogel with a saturation magnetization value of 19.34 emu/g. The nanobioaerogel exhibited fast and high adsorption for Cu(II) (183.96±5.68 mg/g, 29 min), Cd(II) (67.04±1.53 mg/g, 36 min), Cr(VI) (134.49±5.21 mg/g, 45 min) and As(III) (64.62±2.40 mg/g, 40 min) at optimum pH 5.0 and 60 °C in multicomponent system, which is almost four times higher than commercially available activated carbon and other reported literatures. The adsorption process follows the Langmuir isotherm suggesting the monolayer chemisorption, follows pseudo–second order (Cu(II)) and intraparticle diffusion (Cd(II), Cr(VI) and As(III)) models and suggesting rate–limiting step is surface binding and internal pores. ATR–FTIR spectrum revealed that hydroxyl, amine, carboxylate, carbohydrate and iron functional groups in hybrid BGM nanobioaerogel interacted with the heavy metals in a multicomplex manner. It was easily regenerated and reused for multiple adsorptions–desorption cycles. In addition, it also showed >5 log reduction in 4 h against different pathogens and antibiofouling agents. [ABSTRACT FROM AUTHOR]

[Display omitted] • OH groups were introduced to the Si surface after the alkali treatment. • The introduction of OH groups enhances the adsorption capacity of Halloysite. • Cd/Pb promotes H migration in Si-OH and forms covalent bonds with residual O atom. • Si-OH provides a pathway for adsorbing CdCl 2 /PbCl 2 on Si (0 0 1) surface. We attempted to activate the Si surface of Halloysite (Hal) to enhance its adsorption capacity for heavy metal (HM, CdCl 2 /PbCl 2) vapors through thermal-alkali modification. A combination of experimental and simulation methods was used to analyze the stabilization mechanism of CdCl 2 /PbCl 2 comprehensively. FTIR, 1H MAS NMR, and XPS results confirm the generation of Si-OH groups on the alkali-treated Hal (AHal) surface. The adsorption performance of adsorbents was investigated in a two-stage high-temperature adsorption setup, and the results show that a relatively short alkali treatment time (20 min) improved the adsorption capacity of Hal, while a longer treatment time (60 min) led to a negative impact. XPS results revealed that the adsorption of CdCl 2 /PbCl 2 involved both physical and chemical adsorption. Grand Canonical Monte Carlo simulations demonstrated an increased adsorption potential of AHal and enhanced reactivity with the HMs. Density functional theory was employed to investigate the adsorption mechanism of Cd/Pb compounds on the Si surface. Compared to raw Hal, AHal exhibited higher adsorption energy for HMs after introducing Si-OH groups, resulting in a more stable configuration. The stabilization of Cd/Pb monomers on the Si surface primarily relies on promoting the H migration from Si-OH to interlayer O and then forming covalent bonds with the remaining active O atoms, while Si-OH played a role in facilitating the occurrence of De-HCl reaction, thereby transforming the adsorption of metal chlorides into more stable metal monomers adsorption. [ABSTRACT FROM AUTHOR]

• The addition of RM complements the silica-aluminum phase of the FGS system. • The maximum acceptance of alkali by the FGS system is characterized. • FGS has the potential to be used as a non-load bearing material in engineering. • Heavy metals are stabilized by gel adsorption and precipitation. Municipal solid waste incineration fly ash (MFA) and Bayer red mud (RM) were coprocessed with geopolymer technology. The two wastes were used as precursors to synthesize a geopolymer. The ratio of the two wastes and the amount of alkali used, and their effects on the properties of the geopolymer, were investigated. The mechanical properties, mineral compositions, and IR spectra indicated that a 56 d compressive strength of 13.11 MPa was achieved for samples made with 40% MFA and 60% RM and the addition of 7% Na 2 O as the alkali. The alkaline conditions enabled dissolution of the raw materials, a phase change of the aluminosilicate, and a higher degree of polymerization for the gel products. The SEM–EDS and leaching tests showed that gel networks consisting of N-A-S-H and C-(A)-S-H gels immobilized heavy metals by physical wrapping and chemical bonding. A dense matrix limited the release of the toxic elements. The levels of Zn, Ni, Pb, Cu, Cr, and Cd leaching were within the acceptable limits of Chinese and US norms. [ABSTRACT FROM AUTHOR]

[Display omitted] • Identified the potential of nanodiamonds (NDs) as electrocatalysts for chromium. • Modified ND electrode demonstrates superior chromium removal capacity. • Electrosorption system showed improved electrical conductivity via the graphitized NDs. • ND-based redox-assisted flow-through electrosorption system was optimized. Effective removal of hexavalent chromium (Cr(VI)) from water is challenging due to the need for a highly selective process. Efficient chromium removal may potentially be achieved through the use of redox-assisted flow-through electrosorption. In this study, graphitized nanodiamonds (NDs) were annealed under various conditions and the ND with the lowest internal resistance was applied to an activated carbon cloth electrode. The ND-modified electrode was then used as the cathode in a flow-through electrode cell with pristine carbon cloth as the anode. Effective chromium removal was found through a dual pathway mechanism, whereby Cr(VI) is directly electrosorbed at the anode while Cr(VI) is reduced to Cr(III) at the cathode, and subsequently precipitated as Cr(OH) 3 under the locally high cathodic pH conditions. The effects of flow rate and charging/discharging voltage on Cr(VI) removal were further investigated, revealing that sufficiently low flow rates (i.e., ≤1 mL min−1) are required for effective Cr(OH) 3 precipitation and sufficiently high (i.e., >1.4 V) reverse voltages are needed during the discharging period to enable full desorption. Overall, the system displayed high Cr removal capacity (i.e., up to 39.51 µmol g−1) and favorable redox of Cr(VI) to trivalent chromium Cr(III) and Cr(III) to Cr(VI). These results suggest that the ND-modified electrode is a promising tool for the removal of toxic metal ions from wastewater. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel hydrophilicity-tunable CMPA-CS polymer was prepared in-situ. • CMPA-CS exhibits ultrahigh adsorption capacity, rate and selectivity for Hg(II). • CMPA-CS efficiently reduces Hg(II) levels from 0.578 ppm in real water to 1.106 ppb. • The active and abundant O − and N − sites were responsible for Hg(II) adsorption. Conjugated microporous poly(aniline)s (CMPAs) are an intriguing material platform for the selective capture of toxic heavy metal ions from water. However, the hydrophobic, monotonous N heteroatom and microporous properties limit their application scopes, particularly for the in-depth treatment requiring to a parts per billion (ppb) level. Herein, we report a novel chitosan-anchored CMPA (CMPA-CS), as designed through delicately exploiting the chitosan as either adsorption sites or pore templates for CMPA to acquire highly functionalized mesopores that could considerably facilitate Hg(II) adsorption. The CMPA-CS thus displayed excellently wide pH suitability (1.0–13.0), large capacity (862.1 mg g−1), ultrafast removal rate (k 2 = 0.163 mg g−1 min−1), high affinity (K d = 7.1 × 106), and strong anti-interference performance (selectivity of minimum 94.5% under the extreme influence of 100-fold-concentration cations). Besides, the Hg(II) concentration could be decreased from 0.578 ppm to less than 1.106 ppb in Minjiang river water substrates, below the EPR drinking water standards of 2 ppb. Comprehensive characterization revealed that the removal mechanism of Hg (II) was primarily a synergetic chelation reaction from the unique nitrogen ligands and O-containing groups, with the following features intensified: (i) good wettability to increase the interaction between CMPA and Hg(II) as contributed by the plentiful oxygen-containing groups; (ii) hierarchical mesopores that would promote ions transport efficiency as created by the chitosan. The new insight in this work can offer valuable guidelines for the design and structure optimization of CMPAs, facilitating its real-world commercial implementation. [ABSTRACT FROM AUTHOR]

• Modified mangrove filler (MAC) was successfully synthesized. • A green pH-responsive adsorptive modified polylactic acid membrane was prepared. • The highest pure water permeability was 2306.6 ± 97.1 L.m−2.h−1.bar−1 using 3 wt% MAC. • Rejection of Cu, Pb, and Ni reached > 99.95% at pH 10. • 3MAC-PLA exhibited FRR of 72.4% after 4 cycles. A novel green pH-responsive adsorptive membrane was prepared by incorporating amino-activated carbon (AC) modified mangrove particles (MAC) into polylactic acid (PLA) ultrafiltration (UF) membranes via the non-solvent induced phase separation (NIPS) technique. The performance of MAC was investigated at various concentrations (ranging from 0 to 6 wt%). The successful synthesis of the material was confirmed through Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction, and scanning electron microscopy (SEM) coupled with energy-dispersive X-ray (EDS) spectroscopy. The membranes were characterized by SEM, surface zeta potential, pure water permeability, pore size, and porosity analysis, among others. Static adsorption and dynamic filtration were carried out to study the membranes' water permeability and rejection performance of pH responsiveness at pH 4, 7, and 10. The results demonstrated that the addition of MAC improved water permeability from 1336.4 ± 96.4 L.m−2.h−1.bar−1 in the original PLA to 2306.6 ± 9.7 L.m−2.h−1.bar−1 in the 3MAC-PLA membrane (3 wt% MAC). Moreover, the rejection of heavy metal ions increased from 18.15, 17.31, and 17.50% for Cu2+, Pb2+, Ni2+ ions at pH 4, to 99.95, 100, and 99.95% at pH 10 for the 3MAC-PLA membrane; respectively. According to the equilibrium data, the Freundlich isotherm provided the best fit for the experimental data, implying a non-uniform affinity for adsorption on heterogeneous surfaces via chemisorption. The maximum adsorption capacities achieved at pH 7 were 4.2 mg.g−1 for Cu2+, 5.0 mg.g−1 for Ni2+, and 6.8 mg.g−1 for Pb2+; respectively. Overall, the addition of MAC enhanced the properties of the pristine PLA, opening new potential for these composite membranes in the wastewater treatment industry. [ABSTRACT FROM AUTHOR]

This study provides a new idea for the heavy metal ions and organic matter pollution coexisting systems remediation and MFC degradation efficiency optimization. [Display omitted] • The bi-directional promotion effects on heavy metals and organics removal were realized via manganese-iron cycling in the microbial fuel cell (MFC). • The enriched deep-sea bacteria responsible for degrading complex heavy metals and organics were analyzed. • Photocurrent efficiency increases by 0.5-fold in the presence of Fe3+ and Mn4+. • Fe3+ and Mn4+ shuttles electrons for enhanced activation and generation of OH in MFC. With the rapid development of industry and agriculture, the heavy metal ions and organic matter pollution coexistence systems become increasingly common, aggravating environmental damage and endangering water safety. Therefore, an urgent need to find a general method to achieve the typical removal of two pollutants or promote the removal of one to improve another degradation, solving the related pollution problems. Meanwhile, the related research microorganism's salt and heavy metal tolerance is lower, limiting the related research. Therefore, the study makes the deep-sea sediment as the strain source, obtaining the low-valence manganese-oxidizing functional bacteria (OMF) with salt-tolerant and heavy metal-tolerant characteristics, constructing the closed-circuit microbial fuel cell (MFC), carried out the degradation mechanism of saliferous compounding heavy metals-organic wastewater by manganese and iron cycling processes. The results showed that under the salt content conditions of 3%, pH = 6, external resistance of 510 Ω, Mn2+ concentration of 11 g/L, Mn2+:Fe2+ = 1:0.3 and OMF (Rhodococcus erythropolis: Microbacterium kitamiense : Dietzia = 1:2:1) inoculation amount of 20%. The maximum removal rates of organic pollutants (400 mg/L), Cu2+ (250 mg/L), Co2+ (150 mg/L) and Ni2+ (200 mg/L) were 94.72%, 91.23%, 99.89% and 99.97%, respectively. Realizing the heavy metal ions and organic matter pollution coexisting systems purification. The manganese-iron cycle mediated by oxidized low-valent manganese functional bacteria has a dual effect on the pollutant's degradation process through MFC. Firstly, the synergistic redox cycle transformation of iron and manganese promoted the production of OH and accelerated the degradation of organic matter. Secondly, the ferromanganese oxidation products and bio-nanowires enhance material oxidation and electron transfer, improving the organic pollution oxidation and heavy metal ions fixation efficiency. This study provides a new idea for the heavy metal ions and organic matter pollution coexisting systems remediation and MFC degradation efficiency optimization. [ABSTRACT FROM AUTHOR]

[Display omitted] • Co-culture of the two algae had the highest nutrient and metal removal efficiency. • The higher tolerance of Chlorella to metals due to the higher GSH and SOD activities. • There was no significant biomagnification of the metals in the algae-shell food chain. This research the bait microalgae Chlorella sp. and Isochrysis zhangjiangensis were fed to Ruditapes philippinarum (clams) using two types of cultures, monoculture and co-culture, simulating the conditions, and presence, of common heavy metals Cu2+, Pb2+ and Cd2+ in cultured waters. The effects of microalgae growth, antioxidant activity, and changes in nutrient TN and TP were investigated. The metal contents of the culture solution, algal cells, and four tissues of Ruditapes philippinarum were analyzed. The results showed that the highest nutrient removal efficiency was achieved under the co-culture of three heavy metals, with the removal rates of TN and TP ranging from 47.26% to 51.36% and 78.28% to 87.72%, respectively. The higher tolerance of Chlorella sp. to heavy metals compared to Isochrysis zhangjiangensis was probably due to the higher glutathione and super oxide dimutase activities exhibited by Chlorella sp. cells, which increased by 28% and 40.64%, respectively. Isochrysis zhanjiangensis , Chlorella sp. and their co-culture group had the highest removal rate of Pb2+, which were 20.15%, 26.56% and 29.19%, respectively, followed by Cd2+ and Cu2+. The enrichment of the four tissues from the Ruditapes philippinarum organism for heavy metals, was in the order of visceral mass > gill > coat membrane > muscle. The biotransfer coefficients of the three metals in the microalgae- Ruditapes philippinarum food chain biomagnification ranged from 0.24 to 0.79, which indicated that there was no significant biomagnification of the metals in the transfer process of the food chain. The results of this study reveal the mechanism of heavy metal transport in the algae-shellfish system, which would provide a theoretical basis for improving the ecological environment, and can improve the quality of cultured shellfish products. [ABSTRACT FROM AUTHOR]

[Display omitted] • rSBR improve sulfate removal by upregulating dissimilated sulfate reductase. • Bioaugmentation with immobilized rSBR accelerates the metabolism of sulfate. • rSBR remove heavy metals via coprecipitation. • Bio-AnMBR removes approximately 99.4% of sulfate and 95.6% of metal removal. Sulfate-rich metal-laden wastewater (SRMLW) shows a significant threat on the ecological environment and human health. Sulfate-reducing bacteria (SRB) can remove sulfate from wastewater in anaerobic membrane bioreactor (AnMBR). This study constructed recombinant genetic engineered SRB (rSRB) and investigated the sulfate and heavy metals removal efficiency for treating SRMLW by immobilized-microbial bioaugmentation using rSRB (IMrSRB) coupled with AnMBR (Bio-AnMBR). The results show that Bio-AnMBR removed sulfate (99.4%) from SRMLW by upregulating key genes (Sat , DsrAB , AprAB , QmoABC , DsrC and DsrMKJOP) and enzymes (APS reductase, Dissimilatory sulfite reductase, Trithionate reductase and Thiosulfate reductase) in dissimilatory sulfite and sulfate respiration processes. Bio-AnMBR achieved synergistic biodegradation of sulfate and nitrogen by stimulating the activity of these bacteria related to the conversion of nitrogen and sulfate. Microbial analysis indicated that the relatively high abundance of rSRB (79.2%) and functional genes (70.1%) upregulated the activities of key enzymes associated with sulfate metabolism system, thus increasing the production of S (66.4 mg/L) and H 2 S (23.8 mg/L). Bio-AnMBR significantly improved the tolerance to heavy metals by increasing concentrations of CO32–, S2-, and HS-, which was configured to reduce heavy metals (95.6%) via precipitation of metal sulfide (81.3 mg/L), metal carbonates (30.7 mg/L) and metal hydroxides (18.7 mg/L). Bio-AnMBR increased system stability, shorted hydraulic retention time (HRT), decreased the production of soluble microbial products (SMP), extracellular polymeric substances (EPS) and waste-sludge production (WSP), as well as improved effluent quality. In conclusion, data in this study indicate that application of Bio-AnMBR is a feasible strategy for the treatment of SRMLW. [ABSTRACT FROM AUTHOR]

[Display omitted] • MEC for effective simultaneous removal of sulfates and heavy metals.. • Electric fields further enhance the tolerance of heavy metals on microorganisms. • CuS and Cu(OH) 2 are the fate of Cu. • More functional genes related to sulfate metabolism enhanced at low Cu2+ level. It is poorly understood how the mechanism of heavy metals affect sulfate-reducing bacteria (SRB) in microbial electrolysis cell (MEC) system, however, this is essential to improve the effectiveness of sulfate reduction in acid mine drainage (AMD). This study evaluated the impact of Cu2+ on MEC performance using SRBs enriched biocathode. The sulfate reduction rate and pathway, the fate of Cu, as well as the succession of microbial community were investigated. Results showed that MEC performance was optimized at influent Cu2+ concentration of 20 mg/L, while slight inhibition was observed at 40 mg/L. The removal of Cu2+ was accomplished through bioprecipitation and biosorption, forming CuS and Cu(OH) 2. However, MEC performance was inhibited at higher Cu2+ concentrations (60 mg/L) due to damaged cell structure, increased charge transfer internal resistance, and altered microbial communities. Specifically, the relative abundance of Firmicutes and Bacteroidota decreased, and functional genes related to sulfate reduction metabolism were reduced, leading to impairment of the assimilatory and dissimilatory sulfate reduction pathways. This knowledge provides revealing insights and theoretical support for developing a feasible approach to realize the treatment of wastewater containing multiple pollutants. [ABSTRACT FROM AUTHOR]

• A relationship exists between biosorption and bioflocculation in MBFs application. • Heavy metal removal depends on the adsorption but also on the separation of MBFs. • Zeta potential presents a similar profile in the heavy metal hydroxide precipitation. • Three-phase division of zeta potential guides the addition of MBFGA1. • Insufficient precipitation favors the simultaneous biosorption and bioflocculation. The microbial flocculants (MBFs) hold the potential of biosorption to removal the heavy metals. However, it remains unclear what the relationship between biosorption and bioflocculation. Here, during the hydroxide precipitation of Cu, Zn, Pb and Cd, besides the commonly used pH, a three-phase division of zeta potential curves provided an orientation for the addition of MBFs. The plateau phase of zeta potential, indicating an insufficient hydroxide precipitation, was appropriate for introducing MBFGA1, a polysaccharide-based MBF. Its removal capacities on Cu, Zn, Pb and Cd reached the highest of 250 mg/g, 96.7 mg/g, 551.1 mg/g and 233.3 mg/g, respectively. A sufficiently suspended hydroxide precipitates of Pb could receive a higher dosage of MBFGA1, ensure their thorough separation, and finally improve the removal efficiency. In order to further control the residual risk of MBFGA1, the response surface methodology (RSM) was employed to optimize this process. The compromised results improved the Pb removal rate to 98% in a weak acidic solution at pH 6.2. The precipitates composition and crystallinity, the functional groups and the molecular morphology were characterized by the X-ray diffraction (XRD), fourier transform-infrared spectra (FTIRs) and atomic force microscopy (AFM), respectively. The results indicated that the negatively-charged hydroxyl, carbonyl, amino and phosphoryl played the significant roles on fixing the molecular of MBFGA1 on the precipitates, providing the points for the aggregation of flocs, and capturing the residual Pb ions. The insufficient hydroxide precipitation laid the foundation for these multiple functions of MBFGA1, and promoted the synergistic effects between biosorption and bioflocculation. [ABSTRACT FROM AUTHOR]

• β-CD based polymeric adsorbent with an expanded "pocket" structure was created. • PCD-VI exhibited excellent adsorption capacity for organic dyes and heavy metal ions. • Competitive adsorption between organic dyes and heavy metal ions was effectively avoided. • Possible adsorption mechanisms in both mono-component and binary systems were proposed. • Cationic RB and Cd(II) could be recovered separately and PCD-VI could be recycled. The currently reported adsorbents for wastewater purification generally have only limited adsorption capacity towards a single type of pollutant; few of them can simultaneously remove multiple types of pollutants from cocontaminated water with high efficiency. In this work, a kind of β-Cyclodextrin based polymeric adsorbent (PCD-VI) with an expanded "pocket" structure was created, and it exhibited excellent adsorption capacities for different kinds of pollutants, cationic rhodamine B (RB), anionic Congo red (CR) and cadmium ion (Cd(II)) in a mono-component solution. Since the "pocket effect" (composed of cavity inclusion and π-π interactions), electrostatic attraction and coordination were the dominant mechanisms for RB, CR and Cd(II) adsorption, respectively, competitive adsorption was effectively avoided in the simultaneous adsorption process. RB and Cd(II) exhibited a synergistic effect in the RB-Cd(II) binary solution; the coexisting Cd(II) showed a negligible effect on CR adsorption at lower CR concentrations (≤400 mg L−1), while the removal of Cd(II) was prominently promoted by the coexisting CR in the CR-Cd(II) binary system. More importantly, RB and Cd(II) could be recovered separately, and PCD-VI could be recycled without a serious decline in performance even after five sequential adsorption-desorption cycles in the RB-Cd(II) binary system. Our studies suggest promising strategies for fabrication and application of advanced adsorption materials in water pollution remediation. [ABSTRACT FROM AUTHOR]

• The adsorption mechanisms and affecting factors of DWTRs were reviewed. • Application of DWTRs in both wastewater treatment and polluted soil remediation was presented. • Limitation and existing potential modifying methods of DWTRs are discussed. Adsorption has been proved to be an excellent approach for heavy metals and semimetals removal from wastewaters and polluted soils. As an easily, locally & largely available water industrial by-product, drinking water treatment residual (DWTR) has been studied as a low-cost adsorbent for heavy metals and semimetals immobilization in recent years. This opens the two-prong way of beneficial reuse of "waste" for pollution control. In line with the intensive studied in the literature, this review expected to compile an extensive profile from different studies of using DWTRs for heavy metals and semimetals removal. These include Cd, Cr, Co, Cu, Pb, Hg, Ni, Zn, Mo, V, Ga, As, Se, and B. The updated adsorption mechanisms were reviewed. A detailed survey of the literature on the application of DWTR in both wastewater treatment and polluted soil remediation is presented. The limitation and existing potential modifying methods of DWTR are discussed with authors' view of prospects on further DWTRs study. [ABSTRACT FROM AUTHOR]

• The effects of Pb2+ on the DH-α-HH transformation kinetics were investigated. • Four major Pb2+ distribution species were confirmed. • Pb2+ distribution among DH and α-HH were tracked. • Time and dosage dependent Pb2+ evolution in all species were systematically elucidated. The behavior of Pb, a toxic heavy metal that commonly exists in flue gas desulfurization (FGD) gypsum, requires a systematic study for FGD gypsum recycling. In this study, we focus on the role and fate of Pb2+ during the conversion of calcium sulfate dihydrate (DH, the leading component of FGD gypsum) to α-hemihydrate (α-HH) whiskers, in Pb2+ ion-containing ethylene glycol (EG)-water solutions. The results demonstrate that Pb2+ retards DH–α-HH conversion by decreasing the driving force and simultaneously reducing the aspect ratios by shortening the lengths of the whiskers. Four major Pb2+ species, including free Pb2+ ions, Pb2+ in anglesite precipitate, weakly adsorbed Pb2+, and Pb2+ doped onto/into calcium sulfate surfaces are determined to be present. Most Pb2+ is distributed in the solids, while a small amount of Pb2+ moves freely in the solutions. During the induction period of conversion, the majority of Pb2+ is weakly adsorbed on DH, and the remaining Pb2+ exists in anglesite. Upon the initiation of conversion, the anglesite phase starts accumulating, and the adsorbed Pb2+ transfers into the surface lattice of α-HH (denoted as doping Pb2+). The adsorbed Pb2+ on α-HH increases significantly from 0.055 to 1.63 wt% and the doping Pb2+ decreases slightly from 0.82 to 0.76 wt% within a c (Pb2+) initial value of 500–1500 mg/L. Kinetically controlled lattice incorporation accounts for the variation in doping Pb2+. These findings provide new insights into the synthesis of α-HH whiskers, which is influenced by heavy metals and may be useful in FGD gypsum utilization. [ABSTRACT FROM AUTHOR]