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[Display omitted] • The metal adsorption and desorption of membrane can be tuned by pH. • The addition of TA improves the acid resistance of PVDF membranes. • The membrane has a high removal ratio for metals (R>99 %) and oils (R=100 %). Industrial wastewater is complex, containing a significant amount of heavy metals and organics, which needs complicated traditional treatment processes. Ultrafiltration (UF) membranes process can remove various organic pollutants, but exhibit no removal capacity for heavy metal. In this work, we directly blended tannic acid (TA) with polyvinylidene fluoride (PVDF) to fabricate membranes, based on the chelating ability. TA not only improves heavy metal adsorption properties to the membrane but also enhances its acid resistance. The PVDF/TA membrane maintained over 99 % remove rate to Fe3+ in five adsorption–desorption tests and also exhibited effective rejection of bovine serum albumin after the cycling test. The PVDF/TA membrane achieved efficient treating processing of oil and Fe3+ mixed solutions, with 100 % rejection for oil and over 99 % for Fe3+. In this study, the PVDF/TA membranes presented tremendous potential for application in complex wastewater treatment. [ABSTRACT FROM AUTHOR]

• Biochar derived from low-lignin biomass is highly susceptible to oxidation. • Aged low-lignin biochar releases significant DOM, decreasing soil As stability. • Oxygen-functional groups on aged biochar enhance Pb, Zn, and Cu stability. • Cu stability with biochar aging requires further research. Understanding biochar aging is a critical factor in predicting its long-term effects when added to soil. This study explores the complex links between lignin content in biochar feedstock and biochar stability during accelerated aging, including its influence on heavy metal mobility in soil. In this study, nine types of biochar based on fir (F), pine (P), and oak (O) sawdust were produced at 400 °C, and lignin was extracted from them using ammonia after 0, 3, and 7 days (named as 0FB, 3FB, 7FB, 0PB, 3PB, 7PB, 0OB, 3OB, and 7OB). Subsequently, each biochar was subjected to 25 cycles of wet-dry (WD) and freeze–thaw (FT) aging. The aged low-lignin biochars (7FB, 7 PB, and 7OB) released more dissolved organic matter (DOM) and contained more oxygen-containing surface groups on their surfaces than the high-lignin biochars (0FB, 0PB, and 0OB). The low-lignin biochars with high DOM leaching released 37–85 % more anionic arsenic (As) from biochar-amended soil after 25 cycles of aging than the high-lignin biochars. The stabilities of lead (Pb), zinc (Zn), and copper (Cu) were increased due to strong binding to surface functional groups on the low-lignin biochar. The acid-soluble fractions of Pb, Zn, and Cu were converted to organic-bound fractions as biochar aging progressed, with the degree of transformation being inversely proportional to the lignin content of biochar. This research highlights the crucial role of lignin in shaping biochar stability, and reveals how biochar stability impacts soil heavy metals speciation, opening new avenues for effective biochar-based environmental solutions and the promotion of soil health. [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] • 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] • Review the advanced thermal separation methods for heavy metals in MSWI fly ash. • Chlorination of heavy metals by NaCl/KCl requires excitation of Si-Al matrix. • Chlorides make heavy metals more volatile, but molten salts system does not. • XAFS is beneficial for exploring the thermal separation mechanism of heavy metals. • Recovery of heavy metals has good social benefits but poor economic benefits. Municipal solid waste incineration (MSWI) fly ash is categorized as a hazardous waste owing to the presence of heavy metals. The thermal separation of heavy metals from MSWI fly ash has the potential to not only purify the fly ash, but also enable the recovery of heavy metals. The main thermal separation methods include calcination thermal separation (700-1200℃), chlorination thermal separation (700-1000℃), reduction thermal separation (700-1000℃) and molten salts thermal separation (600-800℃). This paper presents a comprehensive review of these four thermal separation methods, comparing them in terms of separation effectiveness, economic feasibility, technical maturity, and environmental impact, etc. Additionally, the possibility of urban mining from MSWI fly ash was evaluated, and the results indicated that while it may be less cost-effective, it could bring significant environmental and social benefits. Finally, the limitations of the existing thermal separation methods and the focus of further research, including both mechanisms and experimental investigations were outlined. [ABSTRACT FROM AUTHOR]

• Metal-organic frameworks (MOFs) has outstanding performance in heavy metal removal. • The synthesis techniques and functionalization methods of MOFs were reviewed. • The applications of different MOFs materials in heavy metal removal are compared and summarized. • The adsorption mechanism of heavy metals removed by MOFs was analyzed and summarized. Worldwide rapid urbanization and development accelerate anthropogenic heavy metals release and dispersion from local to broader areas, posing serious threats to aquatic ecosystems and human health. Although removing various heavy metal ions in aqueous solutions is well explored, current approaches on how to treat heavy metal pollution efficiently and pertinently still need improvement. Adsorption has been identified as the best technique for heavy metal removal, while metal–organic frameworks (MOFs) were considered to be one of the most promising emerging adsorbents capable of addressing complex environmental problems and possessing excellent adsorption properties. Therefore, the synthesis techniques, functionalization methods, and adsorption mechanisms (including adsorption kinetics, adsorption isotherms, etc.) of MOFs to provide optimal solutions for the design, synthesis, and optimization of MOFs were comprehensively reviewed in this work. In addition, a detailed overview and comparison of the applications of pristine MOFs, functionalized MOFs, and MOFs complexes in the removal of heavy metals are also carried out, from which we summarize the adsorption characteristics of various MOFs and give prospects for the development of MOFs. In brief, this review offers a detailed summary of the current information on the removal of heavy metals by MOFs, aiming to provide a strong reference for the synthesis of MOFs and a feasible solution for heavy metal treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • Oxy-fuel co-combustion enriched Zn and Cd in ash with a low environmental risk. • Al-rich textile dyeing sludge immobilized Zn and Cd via enhanced chemisorption. • Cl directly promoted Zn and Cd volatilizations. • Oxy-fuel co-combustion enhanced S retention mainly as CaSO 4 in ash. • Possible reaction and immobilization pathways of the main species were proposed. This study quantified and revealed the temperature and atmosphere dependencies of the enrichment rates and speciation distributions of Zn and Cd and the behaviors of Cl and S for the co-combustion of a hyperaccumulator (SAH) of Zn and Cd and textile dyeing sludge (TDS) at a blend ratio of 3:1 (ST31). The addition of Al-rich TDS to SAH provided the chemisorption sites for Zn and Cd and generated stable Al/Si structures for their stabilization in the ST31 ash. The rising temperature and the atmosphere change from N 2 /O 2 to CO 2 /O 2 transformed Zn and Cd into their oxidizable and residual fractions. Cl promoted the volatilizations of the heavy metals, with its content in the ST31 ash falling from 86.28% at 650 °C to 17.98% at 950 °C. The S content (31.08–33.86%) of the ST31 ash existed mainly as CaSO 4 and was slightly higher in the CO 2 /O 2 than N 2 /O 2 atmosphere (29.45%) since the high CO 2 concentration adversely influenced the decomposition of CaCO 3 , while S indirectly affected the migrations of Zn and Cd. The combined results of the experiments, thermodynamic simulations, and multi-objective optimization pointed to 850 °C in the oxy-fuel atmosphere with 30% O 2 concentration as the optimal settings in order to stabilize Zn and Cd with an acceptable risk. The possible reaction pathways and immobilization mechanisms were also derived considering the interactions among minerals, Zn, Cd, Cl, and S. [ABSTRACT FROM AUTHOR]

• The Cd remediation performance of SRB varied across the sediment profile. • Surface sediment (0–6 cm) was the main remediation range with SRB bioremediation. • SRB bioremediation can inhibit Cd release and bioavailability within the sediment. • The relationship between labile S2- and Cd indicates the remediation performance. • Cd speciation in the sediment was the main factor affecting Cd bioavailability. Sulfate reducing bacteria (SRB) can be utilized for the in-situ remediation of heavy metal contaminated sediment, and the remediation processes occurring at different depths of the sediment profile are critical to the practical application of SRB. In this study, column reactors with sediment profile sampling devices were designed to investigate the variations in Cd speciation, labile S2− and microbial community at different depths of the sediment profile during the bioremediation of Cd contaminated sediment by SRB, over a 270 day monitoring period. In order to evaluate the remediation effect, in vitro extraction of sediment was performed with Sipunculus nudus intestinal juice to determine Cd bioavailability. Results showed that bioremediation caused acid soluble Cd to decrease in the surface sediment (0–6 cm), while reducible and residual fractions of Cd increased. The bioavailability of Cd in the surface sediment reduced by 25.1 % compared to before bioremediation, while no significant changes were observed in other sediment layers. These results indicate that the surface sediment was the main remediation range when SRB were initially added at the water–sediment interface. Furthermore, labile Cd and S2− in the surface sediment of the bioremediation column reactor exhibited a negative correlation (P < 0.1), while they were positively correlated in the sediment profile below 12 cm (P < 0.1) and throughout the whole control column reactor (P < 0.1). This demonstrates that the correlation between labile Cd and S2− could potentially be used as an indicator to reflect the remediation performance. Principal component analysis results revealed that the remediation effect was related to the different Cd fractions, labile S2− and microbial community in the sediment, among which Cd speciation was the most influential factor. Overall, this research provides comprehensive foundation for the practical application of SRB for sediment in-situ remediation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Microbial community and HGT are the key factors of ARGs changes. • Carbon-based materials and clay minerals can decontaminate ARGs and heavy metals. • Functional materials act as adsorbents and alleviate heavy metals to inhibit HGT. • Functional materials change microbial community to slow the VGT of ARGs. Antimicrobial resistance (AMR), especially antibiotic resistance, has posed a huge threat to public health. Moreover, heavy metal, another significant contaminant, can accelerate the generation and dissemination of AMR. Thus, the method and mechanism of AMR removal under heavy metal stress need to be elucidated urgently. Adsorption has been proved to be an important means to deal with AMR pollution. However, there is still a lack of systematic reviews on decontaminating the combined pollution of AMR and heavy metal by adsorption. With this in mind, this review introduces two types of adsorbents, carbon-based materials (biochar and graphene oxide) and clay minerals, which can remove antibiotic resistance genes (ARGs) efficiently even under heavy metal stress. Besides, we summarize the crucial factors affecting the variations of ARGs, and the mechanisms of ARGs removal by two materials under the influences of these factors are proposed. Then, the pathways of two materials to decrease ARGs by reducing heavy metal co-selection and altering microbial communities under heavy metal stress are emphasized. Finally, the bottlenecks of the research on reducing ARGs by these adsorbents and the prior study directions in the future are described in detail. To sum up, the review offers new insight into the mitigation of AMR and heavy metal pollution and facilitates the progress of feasible methods for the removal of ARGs and heavy metal. [ABSTRACT FROM AUTHOR]

[Display omitted] • An review of the effects of ZIF-8 surface modification and functionalization. • Evaluated the application of ZIF-8 based composites for heavy metal removal. • Limitations of ZIF-8 based materials and potential for practical applications. • The mechanism of heavy metal removal is explained by various methods. • Providing theoretical basis and ideas for the study of ZIF-8 based materials. Zeolite imidazolium skeleton-8 (ZIF-8) is a metal–organic framework (MOF) synthetic material with huge specific surface area, diverse structure, adjustable pore size, and easily designed and controlled pore surface characteristics, showing good potential for heavy metal (HMs) removal applications. This makes it a highly sought-after material in wastewater treatment. However, other ZIFs particles tend to clump together in aqueous solutions, resulting in reduced adsorption capacity. In addition, it is difficult to separate them from the water after the removal of contaminants, having poor recoverability. However, ZIF-8 based composite material (ZBC) solved the above problems and was successfully applied to HM in wastewater treatment. This review summarizes the synthetic design approach of ZBC, outlines the influencing factors, theoretical calculations, and characterization of HM removal behavior based on ZBC, as well as the possible interaction pathways. An attempt was made to lay down mechanistic insights for the application of ZBC in practical wastewater treatment and to provide new ideas for the construction of efficient ZBC adsorbents. In addition, the performance of ZIFs and other series of Metal-organic frameworks materials for HM ion removal is objectively compared. Finally, the problems and directions of ZBC in future environmental pollution treatment are discussed to guide the development and practical application of this material. [ABSTRACT FROM AUTHOR]

[Display omitted] • Amine-functionalized biochar was successfully synthesized by coprecipitation. • Amide enhances the adsorption of MgFe 2 O 4 –NH 2 @sRHB without changing its structure. • MgFe 2 O 4 –NH 2 @sRHB kept a stable structure after heavy metal adsorption in wastewater. • MgFe 2 O 4 –NH 2 @sRHB immobilizes soil heavy metals by complexation and functional groups. • MgFe 2 O 4 –NH 2 @sRHB may be a promising deactivator for wastewater and polluted soil. Biochar composites have been widely applied to wastewater and soil remediation due to their advantages of high efficiency, controllability and recyclability. Many studies have demonstrated the application potential of biochar, but little is known about the process and mechanism of surface functionalization of biochar. In this study, an amine-functionalized magnesium ferrite-biochar composite (MgFe 2 O 4 –NH 2 @sRHB) was first synthesized by coprecipitation and then used as a remediation agent to remove heavy metals from aqueous solution and immobilize heavy metals in polluted soils. The results revealed the performance and mechanisms for MgFe 2 O 4 –NH 2 @sRHB to remove or immobilize heavy metals from wastewater or in polluted soils. In wastewater treatment, the mechanisms primarily involved complexation and ion exchange as well as pore filling and electrostatic attraction, and Cd(II) and Pb(II) were adsorbed through a monolayer on the surface of MgFe 2 O 4 –NH 2 @sRHB, with the maximum adsorption capacity reaching 195.50 and 198.93 mg g−1, respectively. In the treatment of soils polluted by heavy metals, MgFe 2 O 4 –NH 2 @sRHB facilitated the transformation of exchangeable Cd to residual and Fe-Mn bound Cd. The addition of 1% MgFe 2 O 4 –NH 2 @sRHB decreased the concentration of exchangeable Cd from 21.0% to 15.2%, 14.8%, 14.8% and 14.6% after 7, 14, 21 and 35 days of treatment, respectively. Electrostatic attraction, precipitation and complexation contributed substantially to the immobilization of heavy metals in the soil. This study provides a new type of biochar composite that can effectively remove and immobilize heavy metals in wastewater and soil at the same time. [ABSTRACT FROM AUTHOR]

• Synthesis of Ti 3 C 2 T X -EDA composite by hydrothermal reaction for adapting as an active layer of nanofiltration membrane. • Controllable surface Zeta potential and active layer thickness. • High pure water flux as a nanofiltration membrane. • High rejection performance against various heavy metal ions. • Stable continuous nanofiltration performance. In a situation in which a huge amount of industrial wastewater is being generated worldwide, developing technology to effectively remove various types of heavy metal ions in wastewater is crucial. To achieve this goal, in this study, a material functionalized with ethylenediamine on Ti 3 C 2 T X is used as the active layer of a nanofiltration membrane to provide excellent rejection against six types of heavy metal ions (Mn2+, Zn2+, Cd2+, Cu2+, Ni2+, and Pb2+). When this Ti 3 C 2 T X -EDA membrane is applied to the nanofiltration system, a heavy metal rejection of greater than 93% is demonstrated, regardless of the heavy metal type with high pure water permeance of 21.1 LMH bar−1 at optimized operating conditions. In particular, for Mn2+, the Ti 3 C 2 T X -EDA membrane demonstrates a high heavy metal rejection of 99.8%. In addition, this membrane exhibit excellent continuous nanofiltration performance for various heavy metal solutions. Because this material can be deposited onto various support membranes, using it as an active layer provides a very efficient approach to achieving heavy metal removal from industrial wastewater. [ABSTRACT FROM AUTHOR]

[Display omitted] • A new tree inspired interfacial solar evaporator was designed for soil remediation. • Selective heavy metal adsorption and photothermal properties were demonstrated. • Evaporation rate reached 3.1 kg m−2h−1 under 1 sun illumination. • Heavy metal (As, Cd, Cr, Pb, Zn) content in soil pore water were reduced by 26–60%. Interfacial solar evaporation is a sustainable and efficient way to enhance water evaporation during seawater desalination and wastewater treatment. In this work, this concept is applied for heavy metal (HM) soil remediation, which is a major global challenge currently limiting food production and endangering human health. Inspired by natural transpiration remediation processes in plants, here a tree inspired evaporator structure is used to accelerate the extraction of HM containing liquids from soil. Coating of simple biomimetic leaf structures with reduced graphene oxide (rGO) can realize a high evaporation rate (3.1 kg m−2h−1) under 1.0 sun illumination. Four-week indoor solar evaporation tests of the evaporator shows that evaporation performance is generally stable and HMs (As, Cd, Cr, Pb, and Zn) in soil pore water are reduced to varying degrees. After solar driven evaporative remediation (SDER) a plant assay in the treated soil shows that relative to an untreated control soil, HM content in broccoli roots decreases by 37.2, 56.4, 25.9, 46.3 and 26.9% for As, Cd, Cr, Pb and Zn, respectively. This work successful demonstrates a new direction in solar evaporator design by enhancing water evaporation to achieve efficient soil contaminant remediation. [ABSTRACT FROM AUTHOR]

• A Solar driven Air Gap Membrane Distillation unit was developed for heavy metal ions removal from wastewater. • Zinc was used as a model contaminant in the wastewater. • A Zinc rejection of 97% and a flux of 0.32 L/m2h was achieved. • Porous activated carbon led to improved membrane characteristics and performance. As the world population grows, pure water becomes increasingly scarce, making wastewater treatment necessary. However, the processes currently used to treat industrial wastewater are generally energy-intensive, highlighting the need to develop environmentally friendly wastewater treatment technologies. To address this issue, a photothermal air–gap membrane distillation system was developed and tested for the first time to remove heavy metal ions from wastewater. Activated carbon particles at different concentrations were used in the prepared polyvinylidene fluoride membranes as components for solar energy recovery. Zinc, one of the most common heavy metals in industrial wastewater in the United Arab Emirates, was used as a model contaminant in this study. The results showed that the use of Activated Carbon particles to modify Polyvinylidene fluoride membranes can significantly improve solar absorption (97%) and porosity (60.6%), resulting in a permeate flux of 0.32 L/m2h and a rejection of 97% of Zn ions. Additionally, the optimized membrane was tested using a synthetic heavy metal solution and showed high rejection rates for most of the tested heavy metals (Zn2+, Fe3+, Cu2+, Cr3+, and Ni2+), which can be potentially used in the industrial heavy metal removal process. The developed photothermal water treatment system can provide a highly efficient and scalable water treatment process. [ABSTRACT FROM AUTHOR]

[Display omitted] • A simple strategy for PEI immobilization by polydopamine coating. • This hybrid adsorbent exhibited excellent Pb(II) adsorption capacity (103 mg/g). • High sorption selectively and rapid kinetics behavior were achieved. • yielding an outstanding capacity of ∼ 6200 L/kg sorbent for the application. Polyethyleneimine (PEI) is a famous chelated reagent for heavy metal capture, but the soluble PEI immobilization always needs complicated chemical procedures. In this work, we explored a simple and green strategy for PEI immobilization and Pb(II) removal by polydopamine (PDA) polymerization. It relies on a cooperative adsorption, originated from the fixation of charged SO 3 H groups inside polystyrene matrix, and in-situ formation of PDA adjugated PEI by simple reaction at ambient temperature. The PDA interface favors the formation of stable adjugated PEI, and the charged SO 3 H groups can drive trace heavy metal ions from bulk solution to the vicinity of branched PEI. These hybrid adsorbents exhibit superior selectivity with a distribution coefficient of 5250 mL/g, rapid kinetics (∼50 mins) and satisfactory sorption-regeneration property in Pb(II) removal. An outstanding capacity of ∼ 6200 L water/kg sorbent and trace effluent (<10 μg/L, WHO) was completed in the treatment of the Pb-contaminated stream. In addition, it also works efficiently for various metals, such as Fe(III), Cu(II) and Ni(II) removal. Our work therefore provides a new method for efficient PEI immobilization and brings a new perspective for mitigating the problem of diverse heavy metal contamination. [ABSTRACT FROM AUTHOR]

RNS-SF possesses long-term stability and excellent immobilization capability. [Display omitted] • RNS-SF remained stable for a long term. • RNS-SF immobilized Pb and Cd efficiently in soils. • High soil moisture favored the immobilization process. • RNS-SF promoted the speciation transformation of heavy metals in soils. Mercapto as an effective functional group for immobilizing heavy metal ions is usually grafted into various materials. However, mercapto is easily oxidized, which limits its practical application to a great extent. Therefore, mercapto iron complex functionalized nanosilica (RNS-SF) was prepared to improve the stability of amendments and the immobilization efficiencies in Pb/Cd-contaminated soil. RNS-SF was characterized with SEM, TEM, FTIR. The long-term stability and immobilization governing factors of RNS-SF were investigated. The results showed that the immobilization efficiencies of Pb and Cd in contaminated soil via RNS-SF were 98.7% and 97.9% with the dosage of 3% (w/w), respectively. Moreover, its immobilization efficiencies remains unchanged from −20 °C to 50 °C. And after 360 days storage at room temperature, the immobilization efficiencies of Pb and Cd were all about 90%. RNS-SF had the best passivation effect on Pb and Cd when the soil moisture maintained at 60% after 6 days aging. Sequential extraction experiments demonstrated that the fractions of EXC species and Carb species of Pb and Cd in the contaminated soil before and after RNS-SF immobilization declined from 22.62% and 43.12% to 0.321% and 0.94%, resulting in substantially reduced environmental risk of Pb and Cd. [ABSTRACT FROM AUTHOR]

[Display omitted] • Innovative treatment for removal Pb (II) from solutions as adherent oxide thin film. • Very simple and efficient treatment without adding reactants at room temperature. • Elimination of 99.99 % of Pb with concentrations directly acceptable for standards. • Total separation of soluble lead to other heavy metals in the optimal conditions. • Successful test on real sample highlighting possible applications. A very simple electrochemical process was developed for a high efficient elimination of Pb(II) from wastewaters. The principle is to remove soluble Pb(II) as oxide(s) adherent thin films only on the effect of an imposed specific potential by chronoamperometric method and an adequate pH, without adding reagents, at room temperature and in a conventional container. This treatment is very efficient for removing 99.99% of Pb(II) and directly reaching acceptable concentrations for the environment and drinking water standards, with low energy input. Firstly, the key parameters that could influence the efficiency of lead removal, such as the pH and the adequate values of potential, the initial concentration and the duration, were studied in pure water. Systematically, the solution was analyzed to quantify the concentration of Pb(II), and the recovered solid as an adherent thin film was characterized by X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS) to determine its nature according to the experimental conditions. In a second part, the same treatment was applied with the optimized conditions in the presence of chemical ionic species and other heavy metals such as Cd(II), Ni(II) or Cu(II) to confirm the possibility to have a total elimination and separation of lead from these other heavy metals. To conclude, this electrochemical process was applied with success on an effluent coming from a wastewater treatment plant (WWTP), which confirms the real interest of this easy electrochemical process for an efficient separation and purification of wastewaters containing soluble lead. [ABSTRACT FROM AUTHOR]

• Convert biomass and metal ions into highly efficient photocatalysts. • Products are composites of metal and hydrothermal carbon (HTCC). • Products can degrade Pharmaceutical and Personal Care Products of ibuprofen. • The metals can increase the charge separation efficiency and activity of HTCC. The degradation of emerging pollutants such as pharmaceutical and personal care products in water is very important. In this study, visible-light-driven metal-hydrothermal carbon composites are synthesized via the facile hydrothermal process, which have high photocatalytic activity for the degradation of ibuprofen. Catalysts are characterized by X-ray diffraction, scanning and transmission electron microscopy, X-ray photoelectron spectroscopy, and UV–vis diffuse reflectance spectrophotometer. These photocatalysts exhibit a light absorption range up to 1300 nm, which are better than many metal oxides or sulfides. Ibuprofen can be degraded within 60 min. The effects of the photocatalytic performance on the ibuprofen degradation efficiency have been studied, such as pH, catalyst dosages, the concentration of H 2 O 2. Various reactive species are detected, including ·OH, e−, h+, and ·O 2 –, while the catalytic mechanism shows that e CB -mediated reactions are essential degradation pathways. Furthermore, metal-HTCC is found to be applicable in real water systems, suggesting this composite is a good candidate photocatalyst for environmental applications. [ABSTRACT FROM AUTHOR]