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Despite the excellent thermometric performance of many developed luminescent nanomaterials, their use has not gone beyond proof‐of‐concept in vivo experiments to date. An important issue that needs to be resolved before moving toward true biomedical applications of engineered nanothermometers is their potential toxicity and bioaccumulation in the human body considering the ultimate objective of clinical applications. Since most reported nanothermometers currently are not degradable materials and are mainly based on the incorporation of heavy metal ions, these aspects remain of genuine concern in the fields of nanomedicine, nanobiotechnology, nanotoxicology, and nanopharmacology. This work explores the possibility of designing visible, as well as near‐infrared, emitting luminescent ratiometric nanothermometers based on appropriate organic dye mixtures embedded in hollow disulfide‐bridged periodic mesoporous organosilica (PMO) particles. Such hybrid particles show excellent thermometric performance in the physiological temperature range (20–50 °C), favorable degradability in simulated physiological conditions, as well as no toxicity to healthy normal human dermal fibroblast (NHDF) cells in a wide concentration range. Considering the simplicity of the approach from the synthetic point of view, and the large available library of known fluorescent dyes emitting in various regions of the electromagnetic range, this motif renders a very promising approach to designing novel non‐toxic, decomposable, luminescent ratiometric thermometers. [ABSTRACT FROM AUTHOR]

Paper-based microfluidics combined with potentiometric measurement has emerged as an attractive approach for detecting various chemical ionic moieties. Detection of heavy metal ions, using paper substrates as solution sampling and delivery systems remains challenging despite efforts to introduce several physico-chemical paper substrate modifications to stop adsorption of ions onto the paper substrates. This study quantitatively investigates the adsorption of heavy metal ions on the paper substrates during paper-based potentiometric measurements and explains the super-Nernstian response of potentiometric sensors through local depletion of heavy metal ions from the solution. Consequently, based on the investigated ion adsorption, a corrective potential protocol was established for the electrodes coupled with paper-based solution sampling by predicting interference free sensor response from paper-based measurement. Furthermore, the ion adsorption was also recorded for mixed metal ion solutions to understand competitive primary/interfering ions adsorption onto the paper substrates and establish corrective measures to predict interference free sensor response. In this method, no modifications of the paper substrates are necessary before actual potentiometric measurements. The proposed corrective protocol allows prediction of sensor response based on the paper-based solution sampling potentiometric measurement, providing a simple methodological approach based on correction of potential readout of the potentiometric sensor, thus completely resigning from the need of modifying paper substrate for measurements of heavy metal ions. [ABSTRACT FROM AUTHOR]

Heavy metal ions can be introduced into the water through several point and non-point sources including leather industry, coal mining, agriculture activity and domestic waste. Regrettably, these toxic heavy metals may pose a threat to both humans and animals, particularly when they infiltrate water and soil. Heavy metal poisoning can lead to many health complications, such as liver and renal dysfunction, dermatological difficulties, and potentially even malignancies. To mitigate the risk of heavy metal ion exposure to humans and animals, it is imperative to extract them from places that have been polluted. Several conventional methods such as ion exchange, reverse osmosis, ultrafiltration, membrane filtration and chemical precipitation have been used for the removal of heavy metal ions. However, these methods have high operation costs and generate secondary pollutants during water treatment. Biosorption is an alternative approach to eliminating heavy metals from water that involves employing eco-friendly and cost-effective biomass. This review is focused on the heavy metal ions contamination in the water, biosorption methods for heavy metal removal and mathematical modeling to explain the behaviour of heavy metal adsorption. This review can be helpful to the researchers to design wastewater treatment plants for sustainable wastewater treatment. [ABSTRACT FROM AUTHOR]

Heavy metals ions as metallic pollutants are a growing global issue due to their adverse effects on the aquatic ecosystem, and human health. Unfortunately, conventional detection methods such as atomic absorption spectrometry exhibit a relatively low limit of detection and hold numerous disadvantages, and therefore, the development of an efficient method for in-situ and real-time detection of heavy metal residues is of great importance. The aptamer-based sensors offer distinct advantages over antibodies and emerged as a robust sensing platform against various heavy metals due to their high sensitivity, ease of production, simple operations, excellent specificity, better stability, low immunogenicity, and cost-effectiveness. The nucleic acid aptamers in conjugation with nanomaterials can bind to the metal ions with good specificity/selectivity and can be used for on-site monitoring of metal ion residues. This review aimed to provide background information about nanomaterials-based aptasensor, recent advancements in aptamer conjunction on nanomaterials surface, the role of nanomaterials in improving signal transduction, recent progress of nanomaterials-based aptasening procedures (from 2010 to 2022), and future perspectives toward the practical applications of nanomaterials-based aptasensors against hazardous metal ions for food safety and environmental monitoring. [ABSTRACT FROM AUTHOR]

Heavy metal ions such as cadmium, mercury, lead, and arsenic in the soil cannot be degraded naturally and are absorbed by crops, leading to accumulation in agricultural products, which poses a serious threat to human health. Therefore, establishing a rapid and efficient method for detecting heavy metal ions in agricultural products is of great significance to ensuring the health and safety. In this study, a novel optimized spectrometric method was developed for the rapid and specific colorimetric detection of cadmium ions based on N-(2-Acetamido)-iminodiacetic acid (ADA) and Victoria blue B (VBB) as the chromogenic unit. The safety evaluation of ADA showed extremely low biological toxicity in cultured cells and live animals. The standard curve is y = 0.0212x + 0.1723, R2 = 0.9978, and LOD = 0.08 μM (0.018 mg/kg). The liner concentrations detection range of cadmium is 0.1–10 μM. An inexpensive paper strip detection method was developed with a detection limit of 0.2 μM to the naked eye and a detection time of less than 1 min. The method was successfully used to assess the cadmium content of rice, soybean, milk, grape, peach, and cabbage, and the results correlated well with those determined by inductively coupled plasma–mass spectrometry (ICP-MS). Thus, our study demonstrated a novel rapid, safe, and economical method for onsite, real-time detection of cadmium ions in agricultural products. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Flexible electronics offer a versatile, rapid, cost-effective and portable solution to monitor water contamination, which poses serious threat to the environment and human health. This review paper presents a comprehensive exploration of the versatile platforms of flexible electronics in the context of heavy metal ion detection in water systems. The review overviews of the fundamental principles of heavy metal ion detection, surveys the state-of-the-art materials and fabrication techniques for flexible sensors, analyses key performance metrics and limitations, and discusses future opportunities and challenges. By highlighting recent advances in nanomaterials, polymers, wireless integration, and sustainability, this review aims to serve as an essential resource for researchers, engineers, and policy makers seeking to address the critical challenge of heavy metal contamination in water resources. The versatile promise of flexible electronics is thoroughly elucidated to inspire continued innovation in this emerging technology arena. [ABSTRACT FROM AUTHOR]

Chromium-contaminated soil is a serious environmental problem that threatens human health and the environment. Electrokinetic technology is used as a promising solution to treat these soils, as it relies on applying an electric field to remove pollutants from the soil. In this study, four experiments were conducted, where experiments have shown that the use of wheat straw as an available, cheap, economical and efficient adsorbent material to prevent the occurrence of reverse osmosis. The results showed that the percentage of removal increased with the increase in the acidity of the medium, that is, as the pH decreased. This is due to an increase in the movement of pollutants as the soil particles become more positively charged, which enhances Attract negative heavy metal ions. This leads to increased movement of heavy metal ions into soil pores, making them more susceptible to transport under the influence of an electric field. The results proved that when using a disinfection solution with a pH of 2, it gave a higher result compared to pH 7 and 12, where the percentage of removal was 78.3%, 62.6 %, and 51.9% respectively. The dissolution of these metals can be enhanced by adding oxalic acid at a constant voltage gradient 1.2 v/cm and an initial concentration of 200 mg/kg. It was noted after the end of the experiment that the percentage of removal reached 81.9%, as the concentration of metals on the cathode side was higher than on the cathode side. The anode, and this is due to the migration of metals under the influence of electromigration to the cathode side, where the chromium concentration was 47 mg/kg at the cathode side, 27 mg/kg at the anode side. [ABSTRACT FROM AUTHOR]

This study presents a new method for detecting and monitoring heavy metal ions in water samples. The method uses liquid crystal‐based optical sensors and a molecular probe called dodecyl‐N‐iminodiacetic acid (DIDAA). The probe's hydrophilic polar diacetate head group acts as a chelator for heavy metal ions, while its hydrophobic non‐polar tail aligns the liquid crystal molecules. When heavy metal ion‐contaminated water samples are introduced, the LC alignment is rapidly disrupted, resulting in bright optical signals. The sensor has a detection limit of 0.1, 0.3, 1.0, and 5.0 μM for for Mercury (Hg2+), Copper (Cu2+), Cadmium (Cd2+), and Lead (Pb2+) respectively. The diacetate probe remains effective even after multiple uses and was not affected by changes in pH. Its activity could persist for over 5 days. Furthermore, this sensor could be reversed and reused to detect HMIs in the presence of EDTA, making it a potential candidate for developing logic gates at the molecular level. [ABSTRACT FROM AUTHOR]

Water pollution with heavy metals owing to industrial and agricultural activities have become a critical dilemma to humans, plants as well as the marine environment. Therefore, it is of great importance that the carcinogenic heavy metals present in wastewater to be eliminated through designing treatment technologies that can remove multiple pollutants. A novel green magnetic nano-composite called (Carbonized Chitosan-Fe3O4-SiO2) was synthesized using Co-precipitation method to adsorb a mixture of heavy metal ions included; cobalt (Co2+), nickel (Ni2+) and copper (Cu2+) ions from aqueous solutions. The novelty of this study was the synthesis of a new nano-composite which was green with magnetic properties to be more sustainable and environmentally friendly. Its magnetic properties made it separated easily from solutions after accomplishment of the adsorption process using a magnet. Extended Freundlich isotherm was the best fitted model with maximum adsorption capacity of the metal ions mixture 2908.92 mg/g. Different experimental parameters have been studied included the initial concentration for a mixture of nickel, cobalt and copper metal ions (0.05–0.1 molar), dosage of adsorbent (0.5–3.5 g/L) and contact time (6–90 min) to investigate their changing effect on the removal percents of the heavy metal ions mixture from aqueous solutions. The experimental adsorption percent of cobalt ion ranged from 1.58 to 64.28%, nickel ion adsorption percent ranged from 10.68 to 94.12% and copper ion adsorption percent ranged from 4.41 to 76.23% at pH = 9 were based on the combination of the adsorption process parameters. [ABSTRACT FROM AUTHOR]

Screen-printed electrodes (SPEs) are reliable, portable, affordable, and versatile electrochemical platforms for the real-time analytical monitoring of emerging analytes in the environmental, clinical, and agricultural fields. The aim of this study was to evaluate the electrochemical behavior of gold screen-printed electrodes (SPGEs) modified with molecules containing amino (Tr-N) or α-aminophosphonate (Tr-P) groups for the selective and sensitive detection of the toxic metal ions Pb2+ and Hg2+ in aqueous samples. After optimizing the analytical parameters (conditioning potential and time, deposition potential and time, pH and concentration of the supporting electrolyte), anodic square wave stripping voltammetry (SWASV) was used to evaluate and compare the electrochemical performance of bare or modified electrodes for the detection of Hg2+ and Pb2+, either alone or in their mixtures in the concentration range between 1 nM and 10 nM. A significative improvement in the detection ability of Pb2+ ions was recorded for the amino-functionalized gold sensor SPGE-N, while the presence of a phosphonate moiety in SPGE-P led to greater sensitivity towards Hg2+ ions. The developed sensors allow the detection of Pb2+ and Hg2+ with a limit of detection (LOD) of 0.41 nM and 35 pM, respectively, below the legal limits for these heavy metal ions in drinking water or food, while the sensitivity was 5.84 µA nM−1cm−2 and 10 µA nM−1cm−2, respectively, for Pb2+ and Hg2+. The reported results are promising for the development of advanced devices for the in situ and cost-effective monitoring of heavy metals, even in trace amounts, in water resources. [ABSTRACT FROM AUTHOR]

In this study, amorphous zirconium phosphate were synthesized (Am-ZrP) through a facile method and then composited with cotton fiber (Am-Co) for the utilization of heavy metal ions adsorptive elimination. In the research, Am-Co exhibited a higher adsorption capacities compared with Am-ZrP, with 85.69 mg/g for Cu2+, 30.73 mg/g for Ni2+, 56.74 mg/g for Cd2+. The adsorption kinetics of the adsorbents was extrapolated using pseudo-first-order and pseudo-second-order kinetic model and the experimental data were found to fit pseudo-second-order more than pseudo-first-order. Langmuir and Freundlich isotherm model were also applied in the study to reflect the interaction between adsorbate and adsorbent. In this research, the adsorption isotherm of Am-ZrP and Am-Co fitted the Langmuir model favorably. The results indicated that the Am-Co was a promising candidate for practical application in the treatment of wastewater contaminated by heavy metal ions. [ABSTRACT FROM AUTHOR]

The use of non ferrous smelting slag to prepare new types of cementitious materials is an important way to realize the resource utilization of solid waste. The gelation mechanism and mechanical properties are the focus of research on non ferrous smelting slag based cementitious materials, and the leaning and solidification mechanisms of heavy metal ions have been receiving increasing attention nowadays. In this article, the morphology and structure of non ferrous smelting slag are described, the existence form and immobilization principle of heavy metal ions in non ferrous smelting slag based cementitious materials are summarized systematically. This review can provide reference for the study of heavy metal immobilization in the application of smelting slag based cementitious materials. [ABSTRACT FROM AUTHOR]

A novel electrochemical sensor based on multiwalled carbon nanotubes (MWCNTs) and 1-butyl-3-methylimidazolium hexafluorophosphate (BMIMPF6) hydrophobic ionic liquid for the rapid detection of Pb2+ and Cd2+ was developed. In this study, the BMIMPF6-MWCNTs composite, as well as BMIMPF6 and MWCNTs, were characterized using SEM. The electrochemical studies were performed using Cyclic Voltammetry (CV) and Electrochemical Impedance Spectroscopy (EIS). The BMIMPF6-MWCNTs/GCE exhibited excellent electrochemical activity. The effect of the pH value of 0.1 M NaAc/HAc buffer, deposition potential, and deposition time was investigated. Under the optimal conditions, the linear range for the modified sensors varies from 5 to 1850 µg L−1 for Pb2+ and 22 to 600 µg L−1 for Cd2+. The limit of detection (LOD) for Pb2+ and Cd2+ was 0.9 µg L−1 and 0.5 µg L−1, respectively, and the limit of quantification (LOQ) was 3 µg L−1 for Pb2+ and 1.7 µg L−1 for Cd2+. Moreover, this method showed excellent anti-interference performance, short analysis time, and practicability for determining Pb2+ and Cd2+. The electrochemical sensor was able to determine heavy metal ions in actual water samples without complex pretreatment, with acceptable recoveries from 98 to 110.8% for Pb2+ and 98.6 to 111.3% for Cd2+, demonstrating that the sensor based on BMIMPF6-MWCNTs/GCE can apply for Pb2+ and Cd2+ quantification. [ABSTRACT FROM AUTHOR]

Ways to increase the efficiency of the electric spark method of wastewater purification from heavy metal ions by increasing the stability of discharges and reducing energy losses are shown. General regularities of changes in the electrical characteristics of a multi-spark underwater discharge distributed in a layer of a mixture of iron and aluminum granules from the parameters of the discharge circuit have been revealed. The dependencies of the power amplitudes of electric spark discharges in a layer of metal granules on time under conditions of different combinations of inductance and capacitance of the discharge circuit are formalized, the regularities of energy input into working reactors to regulate the conditions and efficiency of purification are considered. [ABSTRACT FROM AUTHOR]

Biotreatment of wastewater has attracted considerable attention due to its low cost and eco-friendliness. This study developed a novel bionanocomposite comprised of Nanochitosan (NCS), Bentonite (Bt), and SnO2–ZnO nanocomposite prepared using Salvia officinalis extract as a reducing/stabilizing agent. The NCS/Bt/SnO2–ZnO bionanocomposite exhibited a rough surface with porous nature. EDX, XRD, and FTIR results confirmed the formation of the bionanocomposite. TGA indicated high thermal stability of the NCS/Bt/SnO2–ZnO. DRS results revealed that the bionanocomposite had a band gap of 2.60 eV. The surface area of NCS/Bt/SnO2–ZnO was found to be 32.54 m2 g−1 with a 17.98 nm pore size. Adsorption of Fe(III) and Pb(II) ions and photocatalytic degradation of methylene blue (MB) dye using this bionanocomposite were studied. Under optimal conditions, the highest removal of Fe(III) (99.5%) and Pb(II) (91.5%) was achieved after 5 min and 40 min, respectively. The adsorption data fitted the Langmuir isotherm and indicated the removal capacity of 555.55 and 243.90 mgg−1 for Fe(III) and Pb(II), respectively. Also, the NCS/Bt/SnO2–ZnO showed the MB dye degradation efficiency of 99% within 30 min. Therefore, the NCS/Bt/SnO2–ZnO can be used as an environmentally friendly, cost-effective, thermally stable, and high-performance adsorbent/photocatalyst to remove heavy metal ions and dye molecules. [ABSTRACT FROM AUTHOR]

Core – shell magnetic nanoparticles MCM-41 and nano-clays are working absorbents for elimination of heavy metal ions. Nanoparticles Fe3O4 are made by sol- gel method and are covered by silica and their surfaces are modified with suitable organic compounds. Organic clays also are one of usual absorbents which absorb diverse spectrum of organic pollutants and adsorption function of these compounds is relating to interlayer structure and their surface modification. In present research, for the first time, Kaolinite-NH2@thiazolidinone and Fe3O4@MCM-41-NH2@thiazolidinone nanocomposites were prepared and after structural approval by FTIR, VSM, XRD, SEM, TGA, BET, EDX technics, were used for adsorption of Pb 2 + and Cd2+ from aqueous medium as an active absorbent. to urgent elimination and active heavy metal ions in aqueous solutions, MCM-41 and Kaolinite were modified with (3-aminopropyl) trietoxysilane (APTES) and then during a three-step reaction in condition without solvent with thioglycolic acid and benzaldehyde were reacted and finally, thiazolidinone was synthetized on their surfaces. Adsorption process and different conditions of absorbent dose, metal ion concentration, time and pH have been studied. For optimization conditions, method of response surface (RSM) has been used. 120 tests with two synthetic absorbents were performed for adsorption of Pb2+ and Cd2+, which most capacity of adsorption with the use of Fe3O4@MCM-41-NH2@thiazolidinone was 768.25 mg/g in pH = 5 and 341.5 mg/g in pH = 7.5, respectively. Also, results indicated that most capacity of adsorption with the use of Kaolinite-NH2@Thiazolidin for elimination of Pb2+ and Cd2+ were 552.81 mg/g in pH = 6.5 and 393.21 mg/g in pH = 7.5. Effect of pH, time, absorbent dose, and initial concentration of cations lonely and effect of their simultaneously in adsorption capacity and elimination percentage were evaluated. [ABSTRACT FROM AUTHOR]

Magnetic solid-phase extraction (MSPE) is a highly effective method for separating metal ions from aquatic solutions, making it a popular choice for metal ion separation. This study investigated the behavior of Fe3O4@SiO2-SH core–shell composites for the adsorption and recovery of silver ions. The quality of the synthesized adsorbent was verified using XRD, FT-IR, EDS, FE-SEM, and EDAX-map analyses. Magnetic properties and surface charge changes were assessed using VSM and Zeta potential analyses. By implementing the classic OFAT method, the study evaluated the effect of various parameters on silver adsorption, such as pH, composite dosage, initial Ag+ concentration, temperature, and secondary metal ions. Results showed that the proposed composite had a high maximum adsorption capacity (112 mg/g) at pH = 6, ambient temperature, 0.1 g/L adsorbent dosage, and silver concentrations greater than 25 mg/L. The composite demonstrated good selectivity in Ag+ separation from a bimetallic solution containing silver and mercury ions. The results also showed that 1M HNO3 and 1M HCl solutions released over 78% and 70% of absorbed ions from the composite surface, respectively. However, the HCl solution enabled the precipitation of almost all desorbed Ag+, providing a selective recovery of silver ions. [ABSTRACT FROM AUTHOR]

The massive environmental pollution caused by widespread industrialization jeopardizes human life and ecosystems. Among several pollutants, heavy metal ions in fresh water reservoirs pose a major threat that needs an immediate attention. One of the feasible, cheap and robust approaches to mitigate this pollution is the sorption on efficient and easily available materials. Hence, the contemporary study is designed to the synthesis, characterization, and application of the sodic form of hydroxyethyl cellulose maleate (HEC-MAL-Na) for the selective uptake of Cd(II) metal ions from the spiked aqueous solution. The esterification of hydroxyethyl cellulose (HEC) with maleic anhydride was initially carried out to synthesize HEC-MAL. HEC-MAL was subsequently neutralized by NaHCO3 to form HEC-MAL-Na. The sodic form of HEC-MAL was characterized by comparing the FT-IR spectra of HEC-MAL-Na, HEC-MAL and HEC. Zero-point charge pH of HEC-MAL-Na confirmed the neutralization of HEC-MAL by NaHCO3. HEC-MAL-Na was utilized as an adsorbent for the treatment of polluted water by removing Cd(II) ions via an ion-exchange mechanism. The optimum conditions for the effective removal of Cd(II) ions from the aqueous solution were determined by screening different parameters such as temperature, pH, contact time, sorbent dose and initial metal ion concentration. The experimental data supported the pseudo-second order kinetics and Langmuir isothermal model for removal of Cd(II) ions from aqueous solution with the maximum sorption capacity of 277.7 mg/g at pH 5.5, initial metal ion concentration (110 mg L−1), sorbent dosage (40 mg) and contact time (30 min) at 298 K. The thermodynamic parameters, such as ∆S°, ∆H° and ∆G° were also estimated, and their values indicated the exothermic, spontaneous and feasible nature of the sorption process. Regeneration studies demonstrated the feasibility of the repeated use of activated adsorbent for removal of heavy metal ions. [ABSTRACT FROM AUTHOR]

Purification of emerging heavy metal antimony contaminated water based on advanced ingenious strategies. An activated modified coconut shell charcoal (CSC) was synthesized and evaluated as a substrate-supported loaded organic photovoltaic material, PM6:PYIT:PM6-b-PYIT, to prepare a surprisingly highly efficient, stable, environmentally friendly, and recyclable organic photocatalyst (CSC–N–P.P.P), which showed excellent effects on the simultaneous removal of Sb(III) and Sb(V). The removal efficiency of CSC-N-P.P.P on Sb(III) and Sb(V) reached an amazing 99.9% in quite a short duration of 15 min. At the same time, under ppb level and indoor visible light (~1 W m-2 ), it can be treated to meet the drinking water standards set by the European Union and the U.S. National Environmental Protection Agency in 5 min, and even after 25 cycles of recycling, the efficiency is still maintained at about 80%, in addition to the removal of As (III), Cd (II), Cr (VI), and Pb (II) can also be realized. The catalyst not only solves the problems of low reuse rate, difficult structure adjustment and high energy consumption of traditional photocatalysts but also has strong applicability and practical significance. The pioneering approach provides a much-needed solution strategy for removing highly toxic heavy metal antimony pollution from the environment. [ABSTRACT FROM AUTHOR]

Copyright of Mycosystema is the property of Mycosystema Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A magnetic perovskite-spinel oxide nanocomposite synthesized through a sol–gel self-combustion process is used for the first time as an adsorbent to remove toxic heavy metals (i.e., Pb2+). The synthesized LaFeO3:CoFe2O4 ((LFO)1:(CFO)x) (x = 0.11–0.87) nanocomposites possess good stability, abundant oxygenated active binding sites, and unique structural features, making them suitable for removing divalent Pb2+ ions. Scanning electron microscopy, X-ray diffraction, BET surface area, magnetization measurements, zeta-potential analyses, and X-ray photoelectron spectroscopy were used to analyze the nanocomposites, and their structural changes after Pb2+ ions adsorption. Batch tests confirmed that (LFO)1:(CFO)x efficiently removes Pb2+ from water with a maximum adsorption capacity of 105.96 mg/g. The detailed quantitative study indicates that the interaction of hydroxyl groups with Pb2+ ions occurs through electrostatic interactions and complex formation. We also demonstrate a new ring-magnetic separator system that allows magnetic separation of the toxic ions at a higher speed compared to traditional block magnets. The unique structure, high porosity, large specific surface area, and oxygenated functional groups of (LFO)1:(CFO)x nanocomposites make them promising materials for removal of heavy metal ions and possibly other environmental pollutants. This study provides a new approach to preparing nanocomposites of magnetic spinel ferrites with perovskite oxides for environmental applications. [ABSTRACT FROM AUTHOR]

Porous materials are excellent candidates for water remediation in environmental issues. However, it is still a key challenge to design efficient adsorbents for rapid water purification from various heavy metal ions‐contaminated wastewater in one step. Here, two robust nitrogen‐rich covalent organic frameworks (COFs) bearing terpyridine units on the pore walls by a “bottom‐up” strategy are reported. Benefitting from the strong chelation interaction between the terpyridine units and various heavy metal ions, these two terpyridine COFs show excellent removal efficiency and capability for Pb2+, Hg2+, Cu2+, Ag+, Cd2+, Ni2+, and Cr3+ from water. These COFs are shown to remove such heavy metal ions with >90% of contents at one time after the aqueous metal ions mixture is passed through the COF filter. The nitrogen‐rich features of the COFs also endow them with the capability of capturing iodine vapors, offering the terpyridine COFs the potential for environmental remediation applications. [ABSTRACT FROM AUTHOR]

Medium-density fiberboard (MDF) waste generation has increased steadily over the past decades, and therefore, the investigation of novel methods to recycle this waste is very important. The potential of repurposing MDF waste as an adsorbent for the treatment of Cd(II), Cu(II), Pb(II), and Zn(II) ions in water was investigated using MDF offcuts. The highest adsorption potential in single-metal ion solution systems was observed for Pb(II) ions. The experimental data of Pb(II) ions fit well with the Freundlich isotherm and pseudo-second-order kinetic models. Complexation and electrostatic interactions were identified as the adsorption mechanisms. The adsorption behavior of multi-metal ion adsorption systems was investigated by introducing Cd(II) ions as a competitive metal ion. The presence of the Cd(II) ions reduced the adsorption potential of Pb(II) ions, yet the preference for the Pb(II) ions remained. Regeneration studies were performed by using 0.1 M HCl as a regeneration agent for both systems. Even though a significant amount of adsorbed metal ions were recovered, the adsorption potential of the MDF was reduced in the subsequent adsorption cycles. Based on these results, MDF fines have the potential to be used as an economical adsorbent for remediation of wastewater containing heavy metal ions. [ABSTRACT FROM AUTHOR]

A facilely prepared composite based on Polyvinyl alcohol anchored‐ L‐cysteine (PVA‐L‐CYS) demonstrated efficient functionality in the elimination of heavy metals (Hg, Cr, Pb, and Cd) from working wastewater. The synthesis of the composite was validated through a comprehensive characterization utilizing various analytical techniques to ensure the composite's structural, chemical, and physical properties. At ambient temperature, pH of 4–5.5, interaction time of 15–20 minutes, and concentration of 200 mg/L metal ions, the composite exhibited a maximum retention capacity of 48.5, 25, 45.25, and 44.25 mg/g for Hg, Cr, Pb, and Cd, respectively. Langmuir modeling was establish to be more fitting to the practical results than Freundlich, providing theoretical values of 49.02, 25.97, 46.08, and 44.84 mg/g for Hg, Cr, Pb, and Cd, respectively. The kinetics of PVA‐L‐CYS composite was accurately predicted by model of the pseudo‐first‐order kinetic. Thermodynamic prospects indicated a spontaneous, exothermic, and favorable uptake process at low temperatures. Efficient elution of the heavy metal ions from the overloaded composite was performed using 1 M HNO3. In accordance with WHO and FAO guidelines, the successful elimination of working metal ions from wastewater utilizing the PVA‐L‐CYS composite was demonstrated in a single cycle before discharge into the marine environment. [ABSTRACT FROM AUTHOR]

Access to clean water, hygiene, and sanitation is becoming an increasingly pressing global demand, particularly owing to rapid population growth and urbanization. Phytoremediation utilizes a highly conserved phytochelatin in plants, which captures hazardous heavy metal ions from aquatic environments and sequesters them in vacuoles. Herein, we report the design of phytochelatin-inspired copolymers containing carboxylate and thiolate moieties. Titration calorimetry results indicate that the coexistence of both moieties is essential for the excellent Cd2+ ion-capturing capacity of the copolymers. The obtained dissociation constant, KD ~ 1 nM for Cd2+ ion, is four-to-five orders of magnitude higher than that for peptides mimicking the sequence of endogenous phytochelatin. Furthermore, infrared and nuclear magnetic resonance spectroscopy results unravel the mechanism underlying complex formation at the molecular level. The grafting of 0.1 g bio-inspired copolymers onto silica microparticles and cellulose membranes helps concentrate the copolymer-coated microparticles in ≈3 mL volume to remove Cd2+ ions from 0.3 L of water within 1 h to the drinking water level (<0.03 µM). The obtained results suggest that hyperconfinement of bio-inspired polymers in flow-through systems can be applied for the highly selective removal of harmful contaminants from the environmental water. Access to clean water is a fundamental requirement owing the rapid population growth. Here, the authors report bio-inspired polymers mimicking plant phytochelatin and their hyperconfinement in flow-through systems to enable the selective capture of hazardous heavy metal ions from contaminated water to drinkable level. [ABSTRACT FROM AUTHOR]

Sepsis is a potentially life-threatening condition triggered by pathogens such as bacteria and toxins. In clinical settings, hemoperfusion has been used as a therapeutic technique for the treatment of sepsis to remove pathogens, toxins and other inflammatory mediators from the bloodstream. However, the existing adsorption process of hemoperfusion is not specific to sepsis-related pathogens or toxins, resulting in unsatisfactory removal effectiveness and the lack of capture selectivity. Herein, we developed an ultrasound-responsive asymmetric polymeric microbowl coated with macrophage and red blood cell (RBC) membranes to selectively eliminate pathogens, toxins, and heavy metal ions from blood. Poly(glycidyl methacrylate) spherical microparticles were first synthesized and then eroded using dibutyl phthalate and styrene to form a microbowl structure. This asymmetric structure could provide acoustic radiation pressure gradients to realize orientation motion under non-invasive ultrasound fields with a velocity of 37.14 μm s−1 at 20 Vp–p, which could increase adsorption efficiency in physiological environments by fuel-free programable movements. In addition, the macrophage and RBC membrane coating endowed the microbowl with desired biocompatibility, enhanced blood circulation and the ability to selectively eliminate endotoxins, bacteria and heavy metal ions. Endotoxin removal assay showed that 92.80% of endotoxin was eliminated within 15 minutes. Owing to the affinity between the red blood cell membrane and heavy metal ions, the removal efficiency reached 92.75% and 93.91% for Pb2+ and Hg2+, respectively. Meanwhile, over 90% of S. aureus in the blood was eliminated owing to the selective recognition and adhesion of bacteria by macrophage membrane proteins. Overall, this work on ultrasound-responsive asymmetric polymeric microbowls provides a new insight to eliminate pathogens, toxins and heavy metal ions from the bloodstream for sepsis treatment. [ABSTRACT FROM AUTHOR]

AbstractHeveaBrasiliensis wood sawdust (HBS), a lignocellulosic material, was employed for the eradication of Cd(II), Pb(II), and Ni(II) from synthetic single and multi-metalsystem. In the realm of multimetal adsorption, HBS exhibited the most substantial adsorption capacities for heavy metals, in the order: Pb(II) > Cd(II) > Ni(II). Experiments involving batch process were carried out to explore the rolesofpH, contact duration, HBS quantity, and preliminary metal concentrations on the adsorption capacity. Optimal conditions for biosorption of metal ions were determined as pH 5.0, dosage of 7 gL−1, and an equilibrium time of 90 min. The pseudo-second-order kinetics andLangmuirisotherm had a favorable alignment with the biosorption of all individual metal ions. Adsorption capacity was 8.45, 13.01 and 6.04 mg g− 1 for Cd, Pb and Ni respectively in single metal system. In binary and ternary system the capacity and adsorption percentages decreases significantly due the presence of competitive metal ions. HBS demonstrated effectiveness in treating real wastewater containing Cd2+, Pb2+and Ni2+ ionsin both single and mixed metal solutions, highlighting the necessity of thoroughly considering the impact of competitive adsorption. SEM with EDS results indicated single metal fixing in a multi-ion solution followed complex mechanisms. The surface area and functional group studies were conducted utilizing BET and a FTIR Spectrometer. Electrostatic attraction and complexation mechanisms were identified as responsible factor for capturing metal ions to the active surfaces of the bio sorbent. Cost analysis reflected the adsorbent cost was $0.021 per liter of mixed contaminated ternary effluent (30 mg L−1). [ABSTRACT FROM AUTHOR]

A highly efficient hydrogel derived from D-Mannitol xanthate has been successfully synthesized using a free-radical solution copolymerization technique. An equimolar mixture of acrylonitrile (AN) and acrylic acid (AA) has been reacted with D-Mannitol xanthate (DMX) under inert atmosphere. Three distinct grades of D-Mannitol xanthate-based hydrogels viz. DMXHGs-1, DMXHGs-2, and DMXHGs-3, were prepared. Extensive analyses were conducted on the hydrogels using various methods such as UV, FT-IR, SEM, XRD, GPC, TGA and ΔpHPZC. The maximum swelling ratio of DMXHGs-3 was found to be 52122%, 50434% and 48576% for 24 h with water retention ratio of 80.98%, 78.64% and 79.22% for 30 h in distilled, tap and gray water respectively. These findings indicate the DMXHGs-3 hydrogel has remarkable swelling and water retention capacity. Comprehensive investigations were carried out to evaluate the hydrogel's remarkable adsorption capacity to act as an adsorbent for effectively removing hazardous metal ions. The highest removal percentages of 95.5% and 94.4% and maximum adsorption capacities of 523.56 mg g-1 and 462.96 mg g-1 were observed with DMXHGs-3 hydrogel for Cu2+ and Co2+ ions, respectively. Metal ion removal experiments were conducted by varying several parameters including dosage, pH, temperature, concentration, and time. The quantification of Cu2+ and Co2+ was accomplished using UV–visible spectroscopy. Present studies demonstrate the suitability of D-mannitol xanthate-based hydrogels for the efficient removal of toxic metal ions from wastewater [ABSTRACT FROM AUTHOR]

Novel and facile investigation applying polyethylenimine (PEI) functionalised Single-wall Carbon Nanotubes (SWCNTs) for detection of heavy metal ion, copper (Cu2+) ions has been studied as a nanosensing platform. PEI/SWCNTs shows highly selective and rapid detection of Cu2+ ions since SWCNTs having large surface area shows high porosity and high chemical reactivity towards Cu2+ ions with high stability. FESEM and Raman Spectra measurements have been employed for characterising the nanocomposite and these techniques indicate that the PEI functionalised SWCNTs have been favourably synthesised. The detection of Cu2+ ions on the fabricated PEI/SWCNTs nanocomposite has been carried out by UV-vis spectroscopy. This study illustrates that PEI@SWCNTs nanoplatform is highly sensitive for selective and stable sensing of Cu2+ ions in the range of 0.01 µM to 100 µM with lower limit of detection (LOD) of 6.2 nM in aqueous medium. Selectivity and stability studies suggest that it is a unique and versatile platform for detection of copper ions rather in complex mediums with long-term usability. [ABSTRACT FROM AUTHOR]

Wastewater treatment plants are typically complex because they involve physical, chemical, and biological processes. Meanwhile, the efficiency of the removal of pollutants such as auramine (AO), methylene blue (MB), and ion Cadmium (Cd (II)) from the wastewater are difficult to be measured directly in real-time, as this measurement requires laboratory instruments that are time-consuming. The soft sensors could be the solution to perform the real-time prediction of the AO, MB, and Cd (II) removals' capability. Hence, this study investigates the performances of a soft sensor, namely least-square support vector regression (LSSVR) to estimate the AO, MB, and Cd (II) removals' ability. In this study, two wastewater-related case studies involving AO, MB, and Cd (II) removals were used to evaluate the predictive performance of the LSSVR. Additionally, its results were compared and analyzed with other soft sensors. For both case studies, notice that LSSVR gives the best results for AO, MB, and Cd (II) removals as compared to other soft sensor models where its root means square errors, mean absolute errors, and the approximate error, are lowered by 83% to 1,756%. Moreover, its coefficients of determination, denoted R2 are the highest which are all more than or close to 0.9 for all the AO, MB, and Cd (II) removals even for the testing data for the case studies that were not used to develop the LSSVR model. In conclusion, LSSVR is more suitable for evaluating the effectiveness of the AO, MB, and Cd (II) removals at present. [ABSTRACT FROM AUTHOR]

Heavy metals such as Iron, Copper, and Zinc are micro-essential trace metal and involve animportant biological role, but it quickly turns toxic at exceeding the permissible limit, causing gastrointestinal irritation, liver, bone, and kidney damage, as well as disorders including Wilson's, Parkinson's, and Alzheimer's. It is important to detect the metal ions as well as their concentration quickly and affordable cost using organic probes. Among the organic probes,the coumarin fluorescent probe shows a very prominent candidate with heavy metal ions. Therefore, in the present review, we reviewed the very recent literature the identify the heavy metals using modified coumarin fluorescent probes. Readers will get information quickly about the method of preparation of modified coumarin core and their use as fluorescent probes with heavy metals using absorption and emission spectroscopic methods along with the probable mechanistic pathway of detection. [ABSTRACT FROM AUTHOR]

A novel chitosan (CS) functionalized optical fiber sensor with a bullet-shaped hollow cavity was proposed in this work for the trace concentration of Pb2+ ion detection in the water environment. The sensor is an optical fiber Mach–Zehnder interferometer (MZI), which consists of a sequentially spliced bullet-shaped hollow-core fiber (HCF), thin-core fiber, and another piece of spliced bullet-shaped HCF. The hollow-core fiber is caused to collapse by adjusting the amount of discharge to form a tapered hollow cavity with asymmetric end faces. The bullet-like hollow cavities act as beam expanders and couplers for optical fiber sensors, which were symmetrically spliced at both ends of a section of thin core fiber. The simulation and experiments show that the bullet-like hollow-core tapered cavity excites more cladding modes and is more sensitive to variation in the external environment than the planar and spherical cavities. The ion-imprinted chitosan (IIP-CS) film was fabricated with Pb2+ ion as a template and uniformly coated on the surface for specific recognition of Pb2+. Experimental verification confirms that the developed sensor can achieve high-sensitivity Pb2+ ion detection, with a sensitivity of up to −12.68 pm/ppm and a minimum Pb2+ ion detection concentration of 5.44 ppb Meanwhile, the sensor shows excellent selectivity, repeatability, and stability in the ion detection process, which has huge potential in the direction of heavy metal ion detection in the future. [ABSTRACT FROM AUTHOR]

The issue of food safety has received significant attention in recent years. Heavy metal ions in food can accumulate in living organisms and significantly threaten human health. Therefore, it is crucial to detect heavy metal ions. Conventional instrumental analysis methods have high accuracy, but the disadvantage is the high cost and the complexity of the operation process, so it is very urgent to establish a low-cost, rapid, and continuous detection method for heavy metal ions. Field effect transistor (FET) biosensors are one of the most promising detection tools for heavy metal ion detection due to demonstrated advantages of rapidity, accuracy, and continuity in hazard detection. This review first introduces the structure and principle of graphene FETs in detail, then lists some examples of graphene FETs for detecting common heavy metal ions, and analyzes their advantages and disadvantages in depth. Finally, the development direction of graphene FET biosensors in heavy metal ion detection highlighted in this paper. [ABSTRACT FROM AUTHOR]

Low‐cost, reliable, and efficient biosensors are crucial in detecting residual heavy metal ions (HMIs) in food products. At present, based on distance‐induced localized surface plasmon resonance of noble metal nanoparticles, enzyme‐mimetic reaction of nanozymes, and chelation reaction of metal chelators, the constructed optical sensors have attracted wide attention in HMIs detection. Besides, based on the enrichment and signal amplification strategy of nanomaterials on HMIs and the construction of electrochemical aptamer sensing platforms, the developed electrochemical biosensors have overcome the plague of low sensitivity, poor selectivity, and the inability of multiplexed detection in the optical strategy. Moreover, along with an in‐depth discussion of these different types of biosensors, a detailed overview of the design and application of innovative devices based on these sensing principles was provided, including microfluidic systems, hydrogel‐based platforms, and test strip technologies. Finally, the challenges that hinder commercial application have also been mentioned. Overall, this review aims to establish a theoretical foundation for developing accurate and reliable sensing technologies and devices for HMIs, thereby promoting the widespread application of biosensors in the detection of HMIs in food. [ABSTRACT FROM AUTHOR]

The colorimetric detection of metal ions has witnessed a surge in advancements, with nanostructured fibers emerging as a powerful platform for environmental monitoring and remediation applications. These fibers offer several advantages, including a high surface area, enhanced sensitivity and selectivity, non-intrusive analysis, rapid response times, robustness under harsh conditions, and user-friendly handling. This unique combination makes them particularly suitable for visible eye detection of metal ions in remote or challenging environments. This review provides a concise overview of recent developments in nanostructured fibers, and their cutting-edge fabrication methods, for the colorimetric-based detection of various heavy metal ions in real-time samples. By exploiting the unique properties of these fibers, colorimetric detection offers a promising and cost-effective approach for heavy metal ion determination. This review delves into the design principles, functionalization strategies, and detection mechanisms employed in these innovative sensors. We highlight the potential of nanostructured fibers as a well-established and efficient platform for the colorimetric detection of heavy metals, paving the way for more sustainable and accessible environmental monitoring solutions. [ABSTRACT FROM AUTHOR]

Due to rapid industrialization, novel water-quality monitoring techniques for the detection of highly toxic and hazardous heavy metal ions are essential. Herein, a hybrid noble nanoparticle/DNAzyme electrochemical biosensor is proposed for the simultaneous and label-free detection of Pb2+ and Cr3+ in aqueous solutions. The sensor is based on the combination of a two-dimensional naked-platinum nanoparticle film and DNAzymes, whose double-helix configuration disassembles into smaller fragments in the presence of target-specific heavy metal ions. The electrochemical behavior of the fabricated sensor was investigated with non-faradaic electrochemical impedance spectroscopy (EIS), resulting in the successful detection of Pb2+ and Cr3+ well below their maximum permitted levels in tap water. So far, there has been no report on the successful detection of heavy metal ions utilizing the non-faradaic electrochemical impedance spectroscopy technique based on advanced nanomaterials paired with DNAzymes. This is also one of the few reports on the successful detection of chromium (III) via a sensor incorporating DNAzymes. [ABSTRACT FROM AUTHOR]

Higher education requires learning in the form of practice and research which is often carried out in the laboratories. The research completed in the laboratory usually produces wastewater which not only has a high organic content, but also contains heavy metal ions, such as copper (Cu), cadmium (Cd), and lead (Pb). These heavy metal ions will harm the environment when directly disposed of without being treated first. One of methods to reduce the level of heavy metal ions in laboratory wastewater is adsorption using chitosan. Therefore, this research was focused on removal heavy metal ions in laboratory wastewater by adsorption method using a chitosan derived from fish scales. The objective of this research was to investigate the effect of pH on the removal of Cu, Cd, and Pb ions in the treatment of synthetic wastewater using chitosan. The effect of chitosan dose on the treatment of laboratory wastewater was also examined. Initially, the chitosan was applied in reducing the metal ions in synthetic wastewater. The synthetic wastewater was prepared using single-component and multi-component samples of heavy metal ions. In this study, the pH was varied from 3–7 for application of chitosan on single and multicomponent synthetic wastewater experiments. Optimum pH was produced and then used to remove the metal ions included in the laboratory wastewater sample. The chitosan dose was varied 0.5–2 g/L. As a result, the highest removal percentage for the reduction of Cu, Cd, and Pb metal ions in single-component synthetic wastewater was at pH 7. However, the highest removal percentage for the reduction of Cu, Cd, and Pb metal ions in multicomponent synthetic wastewater were found in different pH, such as Cu ions at pH 5, Cd ions at pH 7, and Pb ions at pH 3. When applied to laboratory wastewater assessments with pH of 7 and chitosan doses of 0.5–2 g/L, the highest percentage removal of Pb ions (93.75%) was reached when using chitosan dosage of 1.5 g/L; the highest percentage removal of Cu ions (28.99%) was obtained when using chitosan dosage of 2 g/L. Alas, the chitosan dose of 0.5–2 g/L did not have a significant effect on reducing the Cd ions. [ABSTRACT FROM AUTHOR]

Environmental pollution by toxic heavy metals is increasing at an alarming rate which demands the development of an appropriate analytical method to investigate and quantify the target analytes. In response to this call, polyaniline Titanium (IV) tungstomolybdate (PANI/TWM) nanocomposite was synthesized by incorporating polyaniline into Titanium (IV) tungstomolybdate using sol–gel method. The material was then characterized using X-ray diffraction (XRD), UV-Vis, Fourier transform infrared (FTIR), Thermogravimetric analysis (TGA-DTA), and Scanning electron microscope (SEM-EDX). It was amorphous with appreciable thermal stability as it retained 65.2% of its ion exchange capacity (IEC) up to 600 OC. It acts as a bifunctional strong acid cation exchanger with an IEC of 1.58 meq/g for Na+ ions. Moreover, the high distribution coefficients (Kd) of 1572 and 928 mL/g for Pb(II) and Co(II), respectively, indicate its potential to treat these ions in an aqueous matrix selectively. Real sample treatment with the prepared material was undertaken for binary separation of selected metal ions in column mode and practically appreciable efficiency (90.3 to 96.8%) was achieved. Therefore, the synthesized material can be considered as a promising cation exchanger to treat an environmental matrix containing toxic heavy metals. [ABSTRACT FROM AUTHOR]

AbstractThis study focuses on the synthesis of three grades of xanthates of natural polymeric material Xanthan gum (XG) by reacting it with Carbon disulfide (CS2) in basic medium at room temperature under inert atmosphere. The confirmation of the formation of Xanthan Gum Xanthates (XGX) has been done with the help of Ultraviolet (UV) spectroscopy, Fourier Transform Infrared (FTIR) spectroscopy, point of zero-charge (PZC), Scanning Electron Microscopy and Energy Dispersive Spectroscopy (SEM-EDS) studies. DSC and XRD studies have been done to confirm the crystalline nature of the xanthates. The removal of Cu2+and Co2+ from the prepared grades was found to be 86.7%, 89.9% and 93.6% for Cu2+ and 86.1%, 88.8% and 93.1% for Co2+ respectively. Therefore, these xanthates can be employed for the eradication of such toxic metal ions from their synthetic solutions. The adsorption capacities of three grades of xanthates viz. XGX1, XGX2, and XGX3 were found to be 319.48, 303.03, and 325.73 mg/g for Cu(II) and 238.66, 246.91, and 230.41 mg/g and for Co(II) respectively, which are better than the adsorption capacities reported for various other adsorbents in literature. [ABSTRACT FROM AUTHOR]

Water constitutes an indispensable resource for global life but remains susceptible to pollution from diverse human activities. To mitigate this issue, researchers are committed to purifying water using a variety of materials to remove harmful chemicals, such as heavy metals. Layered double hydroxides (LDHs), with their intriguing, layered structure and chemical behavior, have attained substantial attention for their effectiveness in removing heavy metal cations and various inorganic oxoanions from water. To enhance the efficiency, considerable endeavors have focused on functionalizing LDHs with different chemical species. Intercalation with metal sulfides has proven to be particularly effective, facilitating heavy metal absorption through multiple mechanisms, including ion-exchange, reductive precipitation, and surface sorption. This review concentrates on the synthesis and performance of polysulfide (Sx, x = 2–5), Mo–S, and Sn–S anion intercalated LDHs for heavy metal cations and inorganic oxoanion sorption, along with their mechanisms. Furthermore, the discussion includes prospects for expanding the chemistry of metal sulfide intercalated LDHs, with existing challenges and future outlooks. [ABSTRACT FROM AUTHOR]

With the rapid development of electronics, the application and research of two-dimensional materials have been at the forefront of the world's scientific research. Black phosphorus (BP) has the advantages of large specific surface area, anisotropy, band tunability, high electrical conductivity and high theoretical specific capacity, which make it very promising for research in the fields of medicine, aerospace and electrochemistry. This paper calculates the electronic structure and adsorption properties of BP in water for different heavy metal ions of Pb 2 + , Hg 2 + and Cd 2 + , including adsorption energy, bandgap, electron density and Mulliken population analysis, based on the first-principles approach of density generalized theory. First principles are quantum mechanical calculations based on density functional theory (DFT), which is a dominant well-developed method in the field of materials simulations, with low errors and high efficiency, especially in systems containing metallic particles. The results showed that the Pb 2 + adsorption system in water was more stable than the Hg 2 + adsorption system and the Cd 2 + adsorption system. The bandgap values of 0.617, 0.785 and 0.715 eV of BP after adsorption of Pb 2 + , Hg 2 + and Cd 2 + in water are smaller compared to 0.891 eV of intrinsic BP, and its properties change from direct bandgap semiconductor to indirect bandgap semiconductor. The higher the stability of a system for the adsorption of different heavy metal ions by BP, the higher the internal electron activity of the adsorption system and the amount of electron transfer. Meanwhile, it is concluded that the electrons mainly transfer from P to heavy metal ions in all the adsorption systems. The electron transfer of the BP-Pb 2 + , Hg 2 + , and Cd 2 + adsorption system occurs mainly in the p, s, and s/p orbitals, respectively. The above content investigated the electronic structure changes and internal electron transfer of heavy metal ions adsorbed by black phosphorus in water, expecting to provide a new reference basis for the detection of heavy metal ions in industrial wastewater using black phosphorus. [ABSTRACT FROM AUTHOR]

Industrialization has brought many environmental problems since its expansion, including heavy metal contamination in water used for agricultural irrigation. This research uses microbial fuel cell technology to generate bioelectricity and remove arsenic, copper, and iron, using contaminated agricultural water as a substrate and Bacillus marisflavi as a biocatalyst. The results obtained for electrical potential and current were 0.798 V and 3.519 mA, respectively, on the sixth day of operation and the pH value was 6.54 with an EC equal to 198.72 mS/cm, with a removal of 99.08, 56.08, and 91.39% of the concentrations of As, Cu, and Fe, respectively, obtained in 72 h. Likewise, total nitrogen concentrations, organic carbon, loss on ignition, dissolved organic carbon, and chemical oxygen demand were reduced by 69.047, 86.922, 85.378, 88.458, and 90.771%, respectively. At the same time, the PDMAX shown was 376.20 ± 15.478 mW/cm2, with a calculated internal resistance of 42.550 ± 12.353 Ω. This technique presents an essential advance in overcoming existing technical barriers because the engineered microbial fuel cells are accessible and scalable. It will generate important value by naturally reducing toxic metals and electrical energy, producing electric currents in a sustainable and affordable way. [ABSTRACT FROM AUTHOR]

With the processes of industrialization and urbanization, heavy metal ion pollution has become a thorny problem in water systems. Among the various technologies developed for the removal of heavy metal ions, the adsorption method is widely studied by researchers and various nanomaterials with good adsorption performances have been prepared during the past decades. In this paper, a variety of novel nanomaterials with excellent adsorption performances for Pb(II) and Cu(II) reported in recent years are reviewed, such as carbon-based materials, clay mineral materials, zero-valent iron and their derivatives, MOFs, nanocomposites, etc. The novel nanomaterials with extremely high adsorption capacity, selectivity and particular nanostructures are summarized and introduced, along with their advantages and disadvantages. And, some future research priorities for the treatment of wastewater are also prospected. [ABSTRACT FROM AUTHOR]

In this work, cotton stalks (Gossypium barbadense) and date palm stones (Phoenix dactylifera) have been used as biosorbents to remove cadmium; Cd(II), lead; Pb(II), and zinc; Zn(II) from mono- and multi-solutions. Each biosorbent was characterized using SEM-EDX, and FT-IR. The findings showed that pH, dose, contact time, metal concentration, and particle size affect the treatment process. The adsorption pattern was Pb(II) > Cd(II) > Zn(II) for both biosorbents. The adsorption performance of cotton stalks was higher than that of date palm stones. The fitted maximum uptake capacities; qm of cotton stalks were higher than those of date palm stones. The maximum adsorption at optimum conditions of Pb(II), Cd(II), and Zn(II) with cotton stalks were 98%, 92.1%, and 78.9%, respectively, within 30 min. While the maximum adsorption of Pb(II), Cd(II), and Zn(II) with date palm stones were 94.6%, 76%, and 68.6%, respectively. Results confirmed the antagonistic effect of heavy metal removal at optimum conditions. Biosorbents could remove ~ 100% of the metal ions from real wastewater samples. Regeneration investigation revealed a successful reusability of both biosorbents for four cycles. [ABSTRACT FROM AUTHOR]