Copper Metal Ions Research Articles

A Nanoporous Supramolecular Metal-Organic Framework Based on a Nucleotide: Interplay of the π···π Interactions Directing Assembly and Geometric Matching of Aromatic Tails.

Self-assembly is the most powerful force for creating ordered supramolecular architectures from simple components under mild conditions. π···π stacking interactions have been widely explored in modern supramolecular chemistry as an attractive reversible noncovalent tool for the nondestructive fabrication of materials for different applications. Here, we report on the self-assembly of cytidine 5’-monophosphate (CMP) nucleotide and copper metal ions for the preparation of a rare nanoporous supramolecular metal-organic framework in water. π···π stacking interactions involving the aromatic groups of the ancillary 2,2’-bipyridine (bipy) ligands drive the self-assemblies of hexameric pseudo-amphiphilic [Cu6(bipy)6(CMP)2(µ-O)Br4]2+ units. Owing to the supramolecular geometric matching between the aromatic tails, a nanoporous crystalline phase with hydrophobic and hydrophilic chiral pores of 1.2 and 0.8 nanometers, respectively, was successfully synthesized. The encoded chiral information, contained on the enantiopure building blocks, is transferred to the final supramolecular structure, assembled in the very unusual topology 8T6. These kinds of materials, owing to chiral channels with chiral active sites from ribose moieties, where the enantioselective recognition can occur, are, in principle, good candidates to carry out efficient separation of enantiomers, better than traditional inorganic and organic porous materials.

Application of Cys A@AuNPs supported amino acids towards rapid and selective identification of Hg(II) and Cu(II) ions in aqueous solution: An innovative microfluidic paper-based (μPADs) colorimetric sensing platform

In this study, an innovative methods was proposed for the synthesis of cysteamine@gold nanoparticle (CysA@AuNPs) using one step protocol. Also, application of CysA@AuNPs for the sensitive recognition of Hg (II) and Cu (II) in aqueous media was investigated using optical techniques. This research work explains the development of a lightweight stamp for manufacturing of a novel microfluidic paper-based analytical device (μPADs), as a simple colorimetric sensor for selective recognition of Hg2+ and Cu2+ within the other metal ions (Fe(III), Mn(II), Zr(IV), Ba(II), Mg(II), Sr(II), As(III), B(III), Al(III), V(III), K(I), Na(I), Mo(II), Co(II), Zn(II), Sn(II), Se(IV), Cr(III), Bi(III)) in aqueous, and human biofluids. CysA@AuNPs supported amino acids were used as the ion detection probs. The specific colorimetric response of Hg2+ and Cu2+ amongst the other ions through the innovative sensor allows naked-eye discrimination of the mercury and copper metal ions in this work with excellent selectivity in the presence of cysteine, and methionine. The results revealed our new strategy (μPADs) for the colorimetric recognition of mercury and copper ions, in both urine and aqueous samples, is selective, simple, fast, sensitive, quantitative, cost-effective, and eco-friendly, which can be detected by naked eye through color alternation with LLOQ of 0.001 ppm for Hg2+, and 0.02 ppm for Cu2+ with admirable stability. The low instrumental needs of the stamp, and disposability of μPADs enable the application of the suggested paper-based device for the commercial diagnostics biosensor.

SORPTION MATERIALS BASED ON ALKALI-INSOLUBLE COMPONENTS PEAT AND BROWN COAL FOR WASTEWATER TREATMENT FROM IONS OF HEAVY METAL

The problem of environmental pollution with heavy metals is relevant for the Republic of Belarus. One of the ways to remove heavy metals from industrial wastewater is to treat them with sorbents. Sorbents based on peat and brown coal are effective and inexpensive, but their use leads to secondary contamination of the treated environment with water-soluble organic compounds. It is shown that the developed sorption materials based on peat and brown coal residues sorb heavy metal ions (copper, nickel, zinc) and do not pollute the treated medium with water-soluble organic compounds (the COС value of sorption materials does not exceed 5 mg O2/dm3). It was found that the exchange capacity of sorption materials in an acidic medium (pH 2.0) is higher than that of humic acids and is in the range of 0.17–1.38 mmol/g. The use of ultrasonic treatment to increase the exchange capacity of sorption materials makes it possible to
 increase it by 2.3–3.0 times for copper ions and 2.2 times for zinc ions, which is due to the destruction of large aggregates.
 The obtained results formed the basis for the development of a technology for obtaining sorption materials for wastewater treatment from heavy metal ions.

Practical and Computational Studies of Bivalence Metal Complexes of Sulfaclozine and Biological Studies.

In the search for novel, metal-based drug complexes that may be of value as anticancer agents, five new transition metal complexes of sulfaclozine (SCZ) with Cu(II), Co(II), Ni(II), Zn(II), and Fe(II) were successfully synthesized. The chemical structure of each complex was characterized using elemental analysis (CHN), IR spectroscopy, UV–Vis spectroscopy, thermogravimetric analysis (TGA), and electronic paramagnetic resonance (EPR) spectroscopy. IR spectra indicated that the donor atoms were one sulfonyl oxygen atom and one pyrazine nitrogen atom, which associated with the metal ions to form a stable hexagonal coordination ring. The metal–ligand stability constant (Kf) revealed that Cu(II) and Ni(II) have good coordination stability among the metal compounds. Theoretical studies using DFT/B3LYP were performed to further validate the proposed structures. The obtained results indicated that Cu(II) has a trigonal bipyramidal geometry, whereas Fe(II), Co(II), and Ni(II) have an octahedral structure, while Zn(II) has a tetrahedral arrangement. The bio-activities of the characterized complexes were evaluated using DNA binding titration and molecular docking. The binding constant values for the metal complexes were promising, with a maximum value for the copper metal ion complex, which was 9 × 105 M-1. Molecular docking simulations were also carried out to evaluate the interaction strength and properties of the synthesized metal complexes with both DNA and selected cancer-relevant proteins. These results were supported by in vitro cytotoxicity assays showing that the Cu(II) and Ni(II) complexes display promising antitumor activity against colon and breast cancer cell lines.

Assessment of heavy metals in soil mining areas of gwanaalkaleri lga bauchi state

Analysis of soil were carried out on mining areas and adjourning farmlands around Gwana in Alkaleri Local Government Area of Bauchi State. The physico–chemical analysis conducted includes pH, electrical conductivity and moisture content which was accompanied by the geochemical characterization and quantification of the metal ions present in the soil. The pH of the soil was within the ranges from 5.6 ±0.01–6.7±0.01, electrical conductivity was within the ranges of 185–290mS/cm and percentage moisture content was within the ranges from 0.42–3.30. the geochemical characterization revealed the presences of chromium (11±0.02 mg/Kg), cobalt (0.1–2.1 mg/Kg), copper (21.9 ±0.01–92.5 ±0.01 mg/Kg), iron (48 ±0.01–174 ±0.01 mg/Kg), lead (7.9 ±0.01–215 ±0.01 mg/Kg), manganese (19.8– 164.8 mg/Kg), nickel (2.9 ±0.01–3.4 ±0.01 mg/Kg), silver (0.4 ±0.01–2.1±0.01 mg/Kg) and zinc (299 ±0.01–417 ±0.01mg/Kg). The concentration of metal ions of copper, lead and zinc in the soil samples collected from the study area revealed that they were excessively above their permissible limit set by the WHO, both in the areas of active mining operations and in the adjourning farmland. Hence the conclusion that the soils where contaminated as a result of the mining activities being carried out within the locality. Based on the high levels of these metal ions in the soils analyzed from the study area, it is hereby recommended that crop samples from within the catchment areas understudy should also be analyzed to evaluate their bioaccumulation coefficient, mobility index and their potential health risk index if any, that may arise from their being exposed to mining activity within the area. Â

Utilization of charcoal rambutan (Nephelium Sp.) adsorbent to remove dissolved copper (II) by natural batch operation

The adsorption ability of rambutan charcoal with the size 100/200 mesh in absorbing dissolved 70 ppm copper metal ions (Cu(II)) at pH 4.5 have evaluated. The adsorption kinetics of rambutan charcoal carried out by natural batch operation. The optimum contact time was 120 minutes with the best removal percentage was obtained 43.84%. The adsorption interaction of copper metal ions on the rambutan charcoal surface has analysed by using SEM-EDX. The kinetic model of the pseudo second-order was applied with interaction with R2 = 0.9816. The result was identified that adsorption occurred chemically. The diffusion kinetic model has indicated the diffusion down to the inter-particle surface of the adsorbent with the value of R2 = 0.8863.

Toxic Metal Ions Removal from Electroplating Wastewater Using Polymer Chelating Ligands

Background: Empty fruit bunch (EFB) is a type of biomass waste product formed during the production process of palm oil. In the present work, EFB was used to prepare a cellulose-graftcopolymer which can be converted into poly(amidoxime)-poly(hydroxamic acid) ligands suitable for the removal of heavy metals from electroplating wastewater. Methods and Results: Poly(amidoxime)-poly(hydroxamic acid) ligands were synthesized from the poly(acrylonitrile-co-methyl acrylate) grafted palm cellulose and were analyzed via FT-IR and FESEM. The binding capacity (qe) with the metals ions such as copper (Cu2+), iron (Fe3+), cobalt (Co2+), nickel (Ni2+) and lead (Pb2+) were 341, 290, 284, 204 and 482 mg g-1, respectively at pH 6. The pseudo-first-order kinetic model is fitted with the results confirming heavy metal adsorption. The isotherm study was conducted using a linear plot of the Langmuir isotherm where results were significantly different from the experimental value (maximum adsorption, qe), indicating that adsorption does not occur on a single layer. However, the coefficient of the correlation values obtained using the Freundlich isotherm model was acceptable (R2>0.99), and it was concluded that adsorption was multilayered with some metal ions. Conclusion: The polymeric ligands synthesized here showed excellent adsorption of heavy metals from electroplating wastewater containing a notable amount of copper and iron metal ions.

Adsorption of Heavy Metal Ions Copper, Cadmium and Nickel by Microcystis aeruginosa

In this study, the average removal rate of cadmium, copper and nickel ions was used as the response value. The initial concentration of heavy metal, culture temperature and initial pH were used as the influencing factors. The response surface experiment was carried out by Box-Benhnken’s central combination design. Based on this, a quadratic regression equation prediction model was established, and the optimal process conditions for the treatment of three heavy metal ions by Microcystis aeruginosa were obtained. Based on the above experimental results, under the optimal conditions for the removal of three metal ions by Microcystis aeruginosa, scanning electron microscopy (SEM) was used to obtain the changes of surface morphology of algal cells before and after removal of heavy metals by algae cells; fourier infrared was used. Combined with the above physical and chemical indicators, the adsorption kinetics model was used to comprehensively analyze and infer the mechanism of treatment of heavy metal ions by Microcystis aeruginosa, and the actual metal wastewater was collected to verify.

A Visually Observable Copper Ion Adsorption Membrane by Electrospinning Combined with Copper Ion Probe

Heavy metal copper ion pollution has enormously threatened ecosystem and public health. So, materials for detecting and adsorbing copper ions (Cu2+) still remains challenging. Electrospinning nanomaterials have good application prospects in the field of water treatment because of its high specific surface area, high porosity and three-dimensional structure. Here, a visualized chitosan/polyacrylonitrile (CS/PAN) nanofiber membrane (NFM) was prepared via the amination modification of the electrospinning membrane and the doping of Cu2+ fluorescent probe to adsorb Cu2+. The effect of membrane absorbs Cu2+ in water was studied from the aspects of initial Cu2+ concentration, PH and adsorption time. It was found that when the pH value of the Cu2+ environment is 5–6, the weight gain rate of aminated nanofiber membrane is 46 %, and the adsorption time is 90 minutes, the adsorption capacity of the NFM can reach 164.3 mg/g. Then, rhodamine hydrazide derivatives were used as fluorescent Cu2+probes, which were added to the spinning solution to prepare new NFM to achieve selective recognition of Cu2+. The membrane can be used multiple times and can achieve gradient color development of different concentrations of Cu2+, and the detection limit can reach 10−8 M.

The Efficacy of Whole Oyster Shells for Removing Copper, Zinc, Chromium, and Cadmium Heavy Metal Ions from Stormwater

This research investigates the use of a common food waste product for removing four different types of metals typically found in stormwater. Whole, unprocessed oyster shells are explored for use in stormwater management infrastructure that addresses water quality concerns. The role of the shells’ surface area, exposure time, and the solution’s initial concentration on the removal efficiency were examined. Beaker scale experimental results demonstrated very good efficiency by the oyster shells for removing copper ions (80–95%), cadmium ions (50–90%), and zinc ions (30–80%) but the shells were not as effective in removing hexavalent chromium (20–60%). There was a positive relationship between initial concentration and removal efficiency for copper and zinc ions, a negative relationship for hexavalent chromium, and no relationship was found for cadmium ions. There was also a positive relationship between surface area and removal efficiency, and exposure time and removal efficiency. However, after a certain exposure time, the increase in removal efficiency was negligible and desorption was occasionally observed. A mid-scale experiment to mimic real-world conditions was conducted in which continuous inflow based on a 6-h design storm was applied to 2.7 kg of whole, unprocessed oyster shells. The shells provided an 86% and an 84% removal efficiency of cadmium and copper ions, respectively, in one day of hydraulic retention time. No removal was observed for hexavalent chromium, and zinc ion removal was only observed after initial leaching. This work has significant implications for sustainable stormwater infrastructure design using a material commonly found in municipal food waste.

Diazo Resin and Acidified Carbon Nanotube Modified Polyacrylonitrile Hollow Fiber Membrane

In this paper, multilayer diazo resin acidified nanotubes/polyacrylonitrile composite films were prepared by grafting diazo resin (DR) and acidified carbon nanotubes (CNT) onto the surface of commercial PAN hollow fiber films by layer by layer self-assembly method. Scanning electron microscopy (SEM), infrared spectroscopy, contact angle, thermogravimetry (TG), water flux and adsorption of heavy metals were used to study. The results showed that the diazo resin (DR) and acidified carbon nanotubes (CNT) were successfully grafted onto PAN Membrane by layer by layer self-assembly method, and carbonyl and carboxyl groups appeared on the surface of modified PAN Membrane; the layer by layer self-assembly did not damage the original morphology of PAN membrane; the hydrophilicity of modified PAN-(DR-CNT)3 membrane was improved, and the water flux was increased. The PAN membrane before and after modification has similar heat and weight loss, and the PAN membrane before and after modification has good thermal stability; the PAN membrane after modification can reach adsorption equilibrium in a relatively short time, and has good adsorption performance for heavy metal copper ions.

Development of Voltammetry Analysis Method of Copper Metal Ions by Solid-State Membrane with Carbon Nanotube

This study was aimed to develop a method for metal analysis in continuous integration using voltammetry techniques. The research subject was copper(II) ions. The objects of research were linearity, scan rate, repeatability of readings, and the presence of Cu(II) levels in well water samples. In this study, a selective electrode was developed with a solid membrane voltammetry system using differential pulse voltammetry measurement. The results showed the regression line of voltammetry method, y = 10.265 ln (x) + 330.47, with a correlation value of 0.9654, the optimum scan rate was 10 mV/s, and within five repetitions of each measurement for one electrode, it showed good repeatability. Meanwhile, the result of regression with the UV-Vis spectrophotometric method for Cu(II) was y = 0.12386x + 0.00879 with a correlation value of 0.9943. The voltammetry method was found to be much better than the UV-Vis method because it was able to be used for analysis up to a concentration of 6.35 × 10–4 ppm (or 1.00 × 10–11 M), while the UV-Vis method was only able to analyze up to 1.5 ppm (or 2.36 × 10–5 M).

Removal of heavy metals from aqueous solutions using carbonised banana and orange peels

This research demonstrates the feasibility and efficacy of removing heavy metals from aqueous solutions using waste banana and orange peels. The fruit peels are carbonised, without the addition of chemical substances, to enhance their adsorption capacities. The adsorption capacities are studied in aquatic solutions containing individual and combined metal ions of hexavalent chromium (Cr6+), copper (Cu) and zinc (Zn). The selectivity of the adsorbents towards these metal ions is also exhibited. The results show that both fruit peels exhibit a better selectivity towards zinc ions, followed by copper and then hexavalent chromium. The effects of operational conditions, including pH, adsorbent dosage, contact time and concentration of metal ions, on the removal efficiency and uptake capacity of the carbonised fruit peels are investigated. The optimal adsorption for both adsorbents occurs within 30 min of exposure and at an adsorbent dose of 0.5 g. Additionally, the adsorption kinetics and isotherms, including pseudo-second-order, Langmuir and Freundlich, are modelled for the obtained data.

Preparation of Porous Mo(VI)-Imprinted Algae for Recognizing Molybdenum(VI)

ABSTRACT In this article, a novel Mo(VI)-imprinted adsorbent based on brown algae (Mo-PVA-SA-I) was synthesized through an ion-imprinting technique in combination with surface imprinting and polymer crosslinking. As the template ion, H3Mo7O24 3 – also acts as the cross-linker to effectively decrease the space and distance between the molecular chains and make the algae form a uniform size of porous structure, it can be used to construct Mo(VI)-matching specific “cavities” after being eluted. Results indicated that the Mo(VI)-imprinted algae have a poor adsorption capacity for its coexisting ions, such as rhenium, copper, iron, zinc, and manganese metal ions at pH 3, while it exhibits apparently higher selective recognition ability for Mo(VI) than the non-imprinted absorbent (Mo-PVA-SA-N). In addition, the prepared Mo(VI)-imprinting algae was equipped with a high adsorption capacity of 114.40 mg·g–1 for Mo(VI). The excellent adsorption performance of this novel Mo-PVA-SA-I adsorbent has been proven to be due to electrostatic attraction between the C = N+–H imine groups and H3Mo7O24 3 – in the “cavities” by both FT-IR and XPS analysis. As a result, this novel and environment-friendly Mo(VI)-imprinted algae will be a promising candidate for recovering Mo(VI) from industrial wastewater.

Synthesis, characterization, biological and electrochemical investigation of copper (II) complexes containing 4-chloro-2-[2, 6-diisopropylphenylimino) methyl] phenol Schiff base ligand and aromatic diinines

Abstract Herein we reported the synthesis of Schiff base ligand and their complexes (1–5) with copper (II) metal ion and aromatic diimines. The Schiff base derived from the condensation of 2, 6- diisopropylaniline and 5- chlorosalicylaldehyde.The Schiff base ligand and their complexes (1–5) have been characterized by microanalysis, molar conductance, room temperature magnetic susceptibility, FT – IR, UV–visible, Cyclic voltammetry and mass spectroscopy techniques. Their low electrical conductance values indicate that the complex 1 is non electrolyte and remaining other complexes 2-5 are in electrolyte nature. The monomeric nature of the complexes is evidenced from their magnetic susceptibility values. The electronic spectra of the complexes suggest that they have distorted octahedral geometry around the metal ion. The electrochemical behavior, the anodic and cathodic peak potential and the number of electron transfer have been calculated by using cyclic voltammetry. These synthesized complexes have been tested against micro-organisms such as S. aureus, B. bacillus (Gram – positive) and E. coli, P. aeruginosa (Gram – negative) bacterial strains with known antibacterial and antifungal drugs (amoxyclav and oxiconazole).

Terbium-functionalized silica nanoparticles for metal ion sensing by fluorescence quenching

We describe preparation of a new luminescent material based on silica nanoparticles functionalized with terbium (Tb3+) complex of a polyamino polycarboxylic chelator, which displayed fluorescence when dispersed in aqueous and organic solvents. The functionalized material, TbL@SiO2, was firstly characterized by FTIR, UV–Vis and photoluminescent (PL) measurements. Further, it was used for various metal ions sensing as monitored by fluorescence quenching, indicating the highest decrease for iron(III), copper(II) and cobalt(II) metal ions. The calculated Stern-Volmer constants (KSV) equalled 2.21 × 105 M−1 for Fe3+, 6.81 × 105 M−1 for Cu2+ and 9.26 × 105 M−1 for Co2+, while the resulted lower detection limits reached 0.17 μM, 0.10 μM and 0.13 μM for Fe3+, Cu2+ and Co2+ respectively. In addition, the quenching mechanism was investigated through lifetime measurements which revealed a dynamic nature upon increase of the transition metal ion concentration. This was evidenced by changes in the emission lifetime (from τ0 = 1600 μs to τq = 1102 μs, thus a decrease of 31% in lifetime in presence of 8.6 μM Cu2+), most probably due to the collision interactions that affected the energy transfer of the ligand towards terbium ions.

Binary Adsorption Studies of Toxic Metal Ions of Lead and Copper from Aqueous Solution by Modified Foeniculum vulgaris Seeds (Fennel Seeds)

Discharge of copper(II) and lead(II) ions into rivers and streams by industries and other human activities has gained serious consideration from regulatory bodies. These toxic metals are harmful to human beings and aquatic life when in high concentrations. Therefore, their removal from wastewater is very important. Hence, this work reports the binary adsorption of toxic metal ions of Cu(II) and Pb(II) from aqueous solution by pristine and modified fennel seeds. Pristine fennel seeds (PFS) were treated with acidic and alkaline solutions to develop modified adsorbents designated ATFS and BTFS, respectively. SEM images revealed that PFS had an amorphous surface with irregular cavities. However, upon acid and base treatment, the surface was more refined. The ATFS had interconnected pores while BTFS had somewhat honeycomb pores. The UV-Vis results confirmed that some of the components were removed from PFS during acid and base pre-treatment. FTIR spectra revealed that the adsorbents had functional groups such as (-OH) and (-C=O), which were involved in the uptake of the metal ions. It was observed that the uptake of Cu(II) and Pb(II) ions onto all adsorbents progressively increased when the initial concentration of the solution was increased. The maximum adsorption capacity was obtained when the initial concentration of the solution was 100 mg/L. The uptake of Cu(II) and Pb(II) on PFS was 3.345 and 11.524 mg/g. While for ATFS 3.78 and 13.07 mg/g and BTFS 8.143 and 14.85 mg/g, respectively. It was observed that the isotherm data fitted Freundlich better for the uptake of both metal ions onto all adsorbents. It was observed that there was a rapid uptake when contact time increased from 5 to 60 min. However, when time increased above 60 min the uptake stabilized and reached equilibrium this was due to the saturation of active sites on the surface for all adsorbents. The kinetics study revealed that PSO fitted the data better than PFO. IPD data revealed that the uptake of metal ions was controlled by the synergistic of ESA and EPA. The ΔHº values for Cu(II) and Pb(II) uptake onto all adsorbents were all negative. This suggested that the reactions were exothermic.

A prudent approach for the removal of copper (II) and cadmium (II) ions from aqueous solutions using indigenous Mactra aequisulcata shells

In this study, the raw seashells of Mactra aequisulcata, of the class Bivalvia and the phylum Mollusca were employed as an adsorbent to remove copper (II) and cadmium (II) metal ions from aqueous solution. The characterization of shells was performed using FTIR, EDX and SEM, BET isotherm and point of zero charge (pHpzc). Batch experiments were performed to assess various factors on the biosorption efficiency. Maximum adsorption of both metals ions conveniently found at 0.4 g L-1 adsorbent dose, pH 5 and at 303 K. Maximum biosorption capacities for Cu2+ and Cd2+ were 59.57 and 38.12 mg g-1, respectively. The Langmuir isotherm model was found to be the best fit for the acquired equilibrium data. Thermodynamic and kinetic parameters showed that the process was feasible, exothermic and followed pseudo-first order.

Adsorption of cationic dyes, drugs and metal from aqueous solutions using a polymer composite of magnetic/β-cyclodextrin/activated charcoal/Na alginate: Isotherm, kinetics and regeneration studies

In this work, we successfully synthesized novel polymer gel beads based on functionalized iron oxide (Fe3O4), activated charcoal (AC) particles with β-cyclodextrin (CD) and sodium alginate (SA) polymer (Fe3O4/CD/AC/SA), by a simple, reproducible and inexpensive method. These beads proved to be versatile and strong adsorbents with magnetic properties and high adsorption capacity. The composites were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy, vibrating sample magnetometry, adsorption at −196 °C, high resolution transmission electron microscopy, thermogravimetric analysis and point of zero charge measurements. Two dyes, two drugs and one metal were used to test the adsorption capability of the prepared polymer nanocomposite. The adsorbent showed good removal efficiencies for the studied pollutants, especially the cationic dyes and the metal, when compared to other low-cost adsorbents. The saturated adsorption capacity of Fe3O4/CD/AC/SA reached 5.882 mg g−1 for methyl violet (MV), 2.283 mg g−1 for brilliant green (BG), 2.551 mg g−1 for norfloxacin (NOX), 3.125 mg g−1 for ciprofloxacin (CPX), 10.10 mg g−1 for copper metal ion (Cu(II)). The adsorption isotherm studies showed that data fitted well with Langmuir and Temkin isotherms models. The kinetic data showed good correlation coefficient with low error function for the pseudo-second order kinetic model. The data analysis was carried out using error and regression coefficient functions for the estimation of best-fitting isotherm and kinetic models, namely: chi-square test (χ2) and sum of the squares of errors (SSE). The activation energy was found to be 47.68 kJ mol−1 for BG, 29.09 kJ mol−1 for MV, 28.93 kJ mol−1 for NOX, 4.53 kJ mol−1 for CPX and 17.08 kJ mol−1 for Cu(II), which represent chemisorption and physisorption behavior of sorbent molecules. The polymer composites can be regenerated and easily separated from aqueous solution without any weight loss. After regeneration, the Fe3O4/CD/AC/SA beads still have good adsorption capacities up to four cycles of desorption and adsorption. The results indicate that the polymer gel beads are promising adsorbents for the removal of different categories of toxicants (like dyes, drugs and metal) in single adsorbate aqueous systems. Thus, the novel Fe3O4/CD/AC/SA beads can be effectively employed for a large-scale applications as environmentally compatible materials for the adsorption of different categories of pollutants.

Construction of the Copper‐Functionalized Covalent Organic Framework Used as a Heterogeneous Catalyst for Click Reaction

AbstractFunctional modification of the covalent organic frameworks (COFs) has become an efficient strategy to expand its applications in various fields. In this investigation, an imine linked T−D COF has been synthesized via solvothermal method using 2,4,6‐tris(4‐aminophenyl)pyridine (TAPP) and 2,6‐dihydroxynaphthalene‐1,5‐dicarbaldehyde (DHNDA) as building blocks. While synthesizing T‐D COF, hydroxyl groups are strategically introduced to the adjacent sites of −C=N− bonds in the framework. Such a special structure enables a strong coordination between the loaded copper metal ion and the hydroxyl groups together with imine bounds in the COF layered structure. The obtained copper‐containing COF, (Cu@T−D COF) hybrid material was used as an efficient heterogeneous catalyst for the alkyne‐azide click chemistry reactions and showed excellent catalytic activity in methanol/water medium. Furthermore, this Cu@T−D COF is stable and easily recycled and reused without loss of its catalytic activity.