Selective Removal Of Copper Research Articles

Selective removal of copper from complex biological media with an agarose-immobilized high-affinity PSP ligand.

The elucidation of metal-dependent biological processes requires selective reagents for manipulating metal ion levels within biological solutions such as growth media or cell lysates. To this end, we immobilized a phosphine sulfide-stabilized phosphine (PSP) ligand on agarose to create a resin for the selective removal of copper from chemically complex biological media through simple filtration or centrifugation. Comprised of a conformationally preorganized phenylene-bridged backbone, the PSP-ligand binds Cu(I) with a 1:1 stoichiometry and exhibits a pH-independent Cu(I) dissociation constant in the low zeptomolar range. Neither Zn(II), Fe(II), nor Mn(II) interact with the ligand at millimolar concentrations, thus offering a much-improved selectivity towards copper over other commonly employed solid-supported chelators such as Chelex 100. As revealed by X-ray fluorescence elemental analysis, the immobilized chelator effectively removes copper from cell culture growth media and cell lysate isolated from mouse fibroblasts. In addition to preparing copper-depleted media or celllysates for biological studies, PSP-immobilized ligands might prove equally useful for applications in radiochemistry, materialsscience, and environmental science.

Surface nanostructuring of Ti40Cu40Zr11Fe3Sn3Ag3 amorphous alloy by alkaline chemical treatment for potential use as a biocompatible material

Amorphous alloys show potential as implant materials due to their superior mechanical properties and good corrosion resistance. However, the presence of toxic elements in the alloy composition can pose challenges, as they can react with the surrounding tissue, leading to inflammation and cell death. To address this, Ti40Cu40Zr11Fe3Sn3Ag3 at% amorphous alloy is developed. This composition comprises of biocompatible elements (Ti, Zr, and Sn) and antimicrobial elements (Ag, Fe, and Cu), for potential use as implant materials. Chemical pseudo-dealloying using a solution of ammonium hydroxide and hydrogen peroxide is employed to selectively remove copper from the sample surface, which may induce toxicity by prolonged contact, and promote the formation of a patterned passivating Ti/Zr oxide-rich surface to enable possible antimicrobial effects. The surface of the samples was analyzed using atomic force microscopy, scanning electron microscopy, and X-ray photoelectron spectroscopy. The modified surfaces show titanium oxide-rich nanostructured topography with depleted amounts of copper from the surface. The kinetics of the selective removal of copper, and the influence of parameters such as electrolyte concentration, immersion time, and stirring velocity on the evolution of morphology were investigated. Our findings elucidate the mechanism of pseudo-dealloying using an ammonia-based solution and demonstrate its efficacy in enhancing the biocompatibility of the alloy. In detail, the pseudo-dealloyed samples exhibited hydrophilic interactions and demonstrated hemocompatibility, making them promising candidates for blood-contacting medical devices. This study underscores the significance of our approach in tailoring the surface properties of amorphous alloys for biomedical applications, paving the way for their utilization in implant materials with improved biocompatibility.

Highly efficient and selective removal of copper from low pH nickel Watts solution through hydrogen sulfide

Highly efficient and selective removal of copper from low pH nickel Watts solution through hydrogen sulfide

Selective removal of copper from heavy-metals-containing acidic solution by a mechanochemical reduction with zero-valent silicon

It is always a challenge to deal with industrial wastewater containing heavy metals. Selective removal and recovery of valuable metals such as copper particularly from acidic solutions are very important from both stances of resource supplying and environmental purification. Among all the divalent heavy metals, copper has the potential of being reduced to monovalent state. A new approach was proposed to ball mill zero-valent silicon (ZVS) in CuSO4 solution and the solutions containing multi-metal ions to serve the purpose. In this study, both quantitative and qualitative data were reported on the induced mechanochemical reduction reaction to convert Cu2+ into Cu2O by ball milling with ZVS. Experimental parameters such as milling time and Si to Cu ratio were found to play important role in stimulating the reaction, and as a result, 97.32% Cu2+ was removed from the solution under Si/Cu molar ratio of 100. Even at a high concentration of sulfuric acid up to 4.6 mol/L, the copper removal percentage maintained a high value of 82.57%. Furthermore, in the sulfate solutions containing several other heavy metals of Zn, Mn, Ni, Cd, Co, Fe etc., the reduction reaction by zero-valent silicon occurred only on Cu2+ with other heavy metal ions remaining in the solutions. The feasibility of this technology has been verified by treating a leaching solution of NiS mineral, from which copper has been removed selectively from nickel, iron etc. This research may serve another purpose for applying waste silicon from the solar energy devices after lifetime in the future.

Selective removal of copper (II) ions from aqueous solution using pyridyl-bridged mesoporous organosilica hybrid adsorbent

The incorporation of active functional groups into the mesoporous organosilica hybrid materials is efficient for various applications. A newly designed mesoporous organosilica adsorbent was prepared using diaminopyridyl groups bridged-(bis-trimethoxy)organosilane (DAPy) precursor by using Pluronic P123 as structure directing template via sol-gel co-condensation method. The hydrolysis reaction of DAPy precursor and tetraethyl orthosilacate (TEOS) with a DAPy content of about 20 mol% to TEOS were incorporated into the mesopore walls of the mesoporous organosilica hybrid nanoparticles (DAPy@MSA NPs). Low-angle XRD and FT-IR, N2 adsorption-desorption analysis, SEM, TEM, and TG analysis were used to characterize the synthesized DAPy@MSA NPs. The DAPy@MSA NPs exhibit an order mesoporous structure with a high surface area, mesopore size and pore volume of approximately ∼465 m2/g, 4.4 nm and 0.48 cm3/g, respectively. The pyridyl groups integrated DAPy@MSA NPs showed the selective adsorption of Cu2+ ions from the aqueous medium by metal-ligand complex coordination of Cu2+ ions with the integrated pyridyl groups and the pendant hydroxyl (-OH) functional groups present into the mesopore walls of the DAPy@MSA NPs. In the presence of other competitive metal ions (Cr2+, Cd2+, Ni2+, Zn2+, and Fe2+), the DAPy@MSA NPs showed relatively high adsorption of Cu2+ ions (276 mg/g) from aqueous solution as compared to the other competitive metal ions at the same concentration (100 mg/L) of initial metal ion solution.

High-Affinity Cu(I)-Chelator with Potential Anti-Tumorigenic Action-A Proof-of-Principle Experimental Study of Human H460 Tumors in the CAM Assay.

Simple SummaryLung cancer is a serious burden worldwide. The growth of lung tumors depends on vessel density and intratumoral copper concentration. Copper chelating agents can reduce copper content in tumor tissue, resulting in lower vessel density and lower tumor weight. PSP-2, a very potent copper chelator, was tested on lung tumor grafts that were on-planted on the chorioallantoic membrane of the chicken embryo. We found a lower vessel density and a lower tumor weight under PSP-2 application compared to the controls. Thus, PSP-2 could be a potential therapeutic agent to treat lung cancer in the future.Human lung cancer ranks among the most frequently treated cancers worldwide. As copper appears critical to angiogenesis and tumor growth, selective removal of copper represents a promising strategy to restrict tumor growth. To this end, we explored the activity of the novel high-affinity membrane-permeant Cu(I) chelator PSP-2 featuring a low-zeptomolar dissociation constant. Using H460 human lung cancer cells, we generated small tumors on the chorioallantoic membrane of the chicken embryo (CAM assay) and studied the effects of topical PSP-2 application on their weight and vessel density after one week. We observed a significant angiosuppression along with a marked decrease in tumor weight under PSP-2 application compared to controls. Moreover, PSP-2 exposure resulted in lower ki67+ cell numbers at a low dose but increased cell count under a high dose. Moreover, HIF-1α+ cells were significantly reduced with low-dose PSP-2 exposure compared to high-dose and control. The total copper content was considerably lower in PSP-2 treated tumors, although statistically not significant. Altogether, PSP-2 shows promising potential as an anti-cancer drug. Nevertheless, further animal experiments and application to different tumor types are mandatory to support these initial findings, paving the way toward clinical trials.

A pyrazine based metal-organic framework for selective removal of copper from strongly acidic solutions

A pyrazine based metal-organic framework for selective removal of copper from strongly acidic solutions

Flexible brushite/nanofibrillated cellulose aerogels for efficient and selective removal of copper(II)

To achieve efficient removal of copper(II) from heavy metal wastewater, designing an eco-friendly and low-cost adsorbent is highly desirable. Here, a novel air- and underwater shape-memory cellulose aerogel was reported via coupling brushite and polyethyleneimine (PEI)-modified nanofibrillated cellulose (NFC) for selectively adsorbing Cu(II) ions. The adsorption kinetic and isotherm studies were consistent with pseudo-second-order model and Langmuir model, indicating the removal of Cu(II) was a monolayer chemisorption process. Benefiting from the open three-dimensional (3D) framework structure and abundant exposed active sites, such compressible aerogel exhibited excellent adsorption capacity of 332.66 mg/g for Cu(II). In addition, the developed aerogel could be conveniently used as a continuous flow filter for successive purification of industrial wastewater, where the up-to-standard treatment volume was about 5.6 L. The Cu(II)-loaded aerogel could be regenerated after being eluted by 0.1 M EDTA-2Na, and its structure, shapeability and selective adsorption properties were hardly affected even after 8 consecutive cycles. Mechanistic analysis confirmed that the surface complexation, ion exchange and chemical deposition were the main driving forces for the superior adsorption performance. Finally, PNFCA/BRU could inhibit the contamination of crops by heavy metals, which was a great safeguard for wheat growth.

Direct synthesis of efficient silica-based adsorbents carrying EDTA groups for the separation of Cu(II) and Ni(II) ions

Cations of copper and nickel belong to the category of heavy metals that coexist in wastewater from the mining and chemical industries and have similar structures. Selective extraction of their soluble forms is an urgent task in ecoanalytical chemistry. In this study, spherical organosilica particles with ethylenediaminetriacetic acid (EDTA) chelating groups were prepared via a one-pot approach for the purpose of Cu(II) and Ni(II) cation extraction from aqueous solutions. The isoelectric point for such samples is observed at pH = 2–3. It was found that the order of introduction of different components (Si(OEt)4, EDTA–silane) into the reaction solution significantly affects the morphology, particle size (672–915 nm) and porosity (260–447 m2 g–1), without affecting the number of chelating groups (0.56–0.59 mmol g–1) and the sorption capacity. The polysilsesquioxane samples acquired from bis-silane with ethylene bridge and EDTA–silane showed a similar number of EDTA groups (0.93–1.11 mmol g–1) regardless of the silane ratio, with the possibility of controlling the specific surface area values (10–431 m2 g–1) and particle size (300–1200 nm) by varying the proportion of bridged silane. The EDTA-polysilsesquioxanes exhibited sorption capacity up to 1.72 mmol g–1 for Cu(II) and 1.53 mmol g–1 for Ni(II). These samples containing EDTA and silanol groups can be effectively used for the selective removal of copper(II) ions from the cationic mixture by varying the initial pH value of the solution.

Highly compressible nanocellulose aerogels with a cellular structure for high-performance adsorption of Cu(II)

Cellulose-based aerogels have considerable potential for various application due to renewable, low cost, and high availability. However, mechanical robustness and functionalization remain major challenges. Here, we synthesized a compressible, recoverable cellulose nanofiber (CNF)/carboxymethyl cellulose (CMC)/branched polyethyleneimine (BPEI) aerogel via electrostatic-modulated interfacial covalent crosslinking and freeze-drying process. The porous BPEI@CNF/CMC aerogel possessed excellent mechanical compression and high-density metal-chelating groups, which exhibited fast adsorption kinetics and high adsorption capacity (452.49 mg g−1) in static copper adsorption process. Furthermore, BPEI@CNF/CMC aerogels displayed excellent recyclability and could still reach 85% after 10 cycles. The integrated analyses of ATR-FTIR and XPS suggested that the predominant adsorption mechanism included electrostatic interaction, ion-exchange and chelation. This strategy provides a sustainable route to fabricate efficient biomass-based adsorbents for selective copper removal from water.

Highly Efficient and Selective Removal of Copper from Nickel Watts Baths Using Hydrogen Sulfide

Highly Efficient and Selective Removal of Copper from Nickel Watts Baths Using Hydrogen Sulfide

Mesoscopic engineering materials for visual detection and selective removal of copper ions from drinking and waste water sources

The monitoring and removal of abundant heavy metals such as Cu ions are considerable global concerns because of their severe impact on the health of humans and other living organisms. To meet this global challenge, we engineered a novel mesoscopic capture protocol for the highly selective removal and visual monitoring of copper (Cu2+) ions from wide-ranging water sources. The capture hierarchy carriers featured three-dimensional, microsized MgO mesoarchitecture rectangular sheet-like mosaics that were randomly built in horizontal and vertical directions, uniformly arranged sheet faces, corners, and edges, smoothly quadrilateral surface coverage for strong Cu2+-to-ligand binding exposure, and multidiffusible pathways. The Cu2+ ion-selectively active captor surface design was engineered through the simple incorporation/encapsulation of a synthetic molecular chelation agent into hierarchical mesoporous MgO rectangular sheet platforms to produce a selective, visual mesoscopic captor (VMC). The nanoscale VMC dressing of MgO rectangular mosaic hierarchy by molecularly electron-enriched chelates with actively double core bindings of azo- and sulfonamide- groups and hydrophobic dodecyl tail showed potential to selectively trap and efficiently remove ultratrace Cu2+-ions with an extreme removal capability of ~233 mg/g from watery solutions, such as drinking water, hospital effluent, and food-processing wastewater at specific pH values. In addition to the Cu2+ ion-selective removal, the VMC design enabled the continuous visual monitoring of ultratrace Cu2+ ions (~3.35 × 10−8 M) as a consequence of strong chelate-to-Cu2+ binding events among all accumulated matrices in water sources. Our experimental recycle protocol provided evidence of reusability and recyclability of VMC (≥10 cycles). With our mesoscopic capture protocol, the VMC can be a promising candidate for the selective decontamination/removal and sensitive detection of hazardous inorganic pollutants from different water sources with indoor or outdoor applications.

A nature-inspired hydrogen-bonded supramolecular complex for selective copper ion removal from water

Herein, we present a scalable approach for the synthesis of a hydrogen-bonded organic–inorganic framework via coordination-driven supramolecular chemistry, for efficient remediation of trace heavy metal ions from water. In particular, using copper as our model ion of interest and inspired by nature’s use of histidine residues within the active sites of various copper binding proteins, we design a framework featuring pendant imidazole rings and copper-chelating salicylaldoxime, known as zinc imidazole salicylaldoxime supramolecule. This material is water-stable and exhibits unprecedented adsorption kinetics, up to 50 times faster than state-of-the-art materials for selective copper ion capture from water. Furthermore, selective copper removal is achieved using this material in a pH range that was proven ineffective with previously reported metal–organic frameworks. Molecular dynamics simulations show that this supramolecule can reversibly breathe water through lattice expansion and contraction, and that water is initially transported into the lattice through hopping between hydrogen-bond sites.

Efficient and selective removal of copper from aqueous solution by nanosized hydrated zirconium oxides loaded in vermiculite

Novel nanosized hydrated zirconium oxide (ZrO(OH)2) loaded in vermiculite (VMT) was successfully prepared and used to remove Cu2+ from aqueous solution. The adsorbent was characterized by XRF, XRD, SEM and TEM. The adsorption process of Cu2+ could reach equilibrium within 30 min and its kinetic data could be well described by pseudo-second-order model. The isotherm data could be described better by Langmuir model and the calculated maximum adsorption capacity was 96.23 mg/g. The adsorption of Cu2+ on nanosized ZrO(OH)2 loaded in vermiculite (NZV) was intensively affected by solution pH and different electrolytes. NaClO4 inhibited the adsorption of Cu2+, while NaCl and NaNO3 promoted the Cu2+ adsorption on NZV. The adsorption enhancement by NaNO3 was much significant than that of NaCl due to more ternary complexes forming among Cu2+, NO3- and the surface of NZV. The adsorption speed and capacity of Cu2+ were apparently reduced in the presence of Ni2+ in solution, while Cu2+ showed a higher affinity to adsorbent than Ni2+. The selective adsorption of Cu2+ in Cu-Ni mixed solution could be easily achieved in the presence of 0.8 mol/L of NaNO3, leading to 100% removal of Cu2+ and around 5% removal of Ni2+.

Selective removal of copper and cobalt from aqueous environment using new Cu(II) and Co(II) imprinted polymer and their determination by flame atomic absorption spectrophotometry

Selective removal of copper and cobalt from aqueous environment using new Cu(II) and Co(II) imprinted polymer and their determination by flame atomic absorption spectrophotometry

Dual use of colorimetric sensor and selective copper removal from aqueous media with novel p(HEMA-co-TACYC) hydrogels: Cyclen derivative as both monomer and crosslinker

Within the scope of this study, p(2-hydroxyethyl methacrylate-co-tetraacrylic cyclen) (p(HEMA-co-TACYC)) hydrogels were synthesized for the first time in the literature using a tetraacrylic cyclen (TACYC) as both functional monomer and crosslinker. The hydrogels designed especially for Cu2+ ions showed colorimetric sensor behavior selective for Cu2+ ions in all aqueous media (deionized, tap, river and sea water) and in metal ion mixtures. The p(HEMA-co-TACYC) hydrogels forming a stable complex with Cu2+ ions simultaneously showed properties of being a good adsorbent material. The hydrogels have reuse capacity as both sensor and adsorbent material. Changing the amount of TACYC in the hydrogel structure changes the maximum adsorption capacity for Cu2+ ions. The Langmuir and Freundlich adsorption constants for Cu2+ ion adsorption of the hydrogels, acting as selective adsorbent in all aqueous media and metal ion mixtures, were determined.

New method for hydrogel synthesis from diphenylcarbazide chitosan for selective copper removal

In this work, a simple method was developed for hydrogel preparation from 1,5-Diphenylcarbazide (DPC) and chitosan (CS) through Diazotization reaction of CS as a selective adsorbent (DPCCS) for Cu(II) ions. CS was treated with sodium nitrate and subsequent crosslinking reaction with DPC for the preparation of DPCCS. Different techniques were used for characterization of DPCCS. Various parameters such as, temperature, pH, and concentration of Cu(II) were used for adsorption studies. Kinetics of Cu(II) ion on DPCCS follows the Pseudo second order and equilibrium of adsorption occurs in short time. The equilibrium data was best fitted with the Langmuir isotherm and the maximum adsorption capacity of DPCCS was 185.505 mg g−1. Thermodynamic parameters ΔG°, ΔH° and ΔS° suggested that the adsorption of Cu(II) ion on the surfaces of DPCCS was spontaneous, endothermic and randomness of Cu(II) ion in the solution was enhanced respectively. Regeneration of DPCCS and Cu(II) ion recovery were studied up to five cycles without the lost of the adsorption capacity.

Selective removal of copper from the artificial nickel electrolysis anolyte by a novel chelating resin: batch, column and mechanisms

The selective removal of copper from the artificial nickel electrolysis anolyte was presented with a novel N-octyl-2-aminomethylpyridine-funcionalized chelating resin (abbreviated as CP-AMPO) in this study. In the single system, the adsorption characters of the CP-AMPO resins for Cu2+ and Ni2+ were examined through pH of solution, concentration of metal ions, contact time and temperature. Through the experimental investigation, the isotherm adsorption behavior of Cu2+ fitted well with Langmuir isotherm, whereas the adsorption behavior of Ni2+ followed the Langmuir and the Freundlich isotherm. The kinetic adsorption parameters were proved to be in agreement with the pseudo-second kinetic model, the thermodynamics data demonstrated the adsorption behaviors of Cu2+ and Ni2+ were a spontaneous and endothermic process. Additionally, from the competitive adsorption in the binary systems, the separation factor of copper/nickel reached 2000, indicating higher selectivity for copper over nickel. Moreover, the residual concentration of copper was less than 3 mg/L at the beginning of 8 BV in the artificial nickel electrolysis anolyte after purification and the mass ratio of copper/nickel exceeded 15 in the saturated resins by the dynamic adsorption curves. The results could well satisfy the production requirement of the nickel electro-refining procedure. Therefore, the CP-AMPO resins could be used as the high-performance adsorbent to remove copper from the nickel electrolysis anolyte in the large-scale industry. Consequently, the extended study of the chelating resin on the mechanisms of selective adsorption for copper and nickel was assessed by X-ray photoelectron spectroscopy (XPS).

Label-free gold nanorod-based plasmonic sensing of arsenic(iii) in contaminated water.

In this paper, we report a strategy based on unmodified gold nanorods for sensitive and selective detection of arsenic(iii) in contaminated water for the first time. The strategy relies on the inhibitory effect of arsenic(iii) on iron(iii)-mediated oxidative shortening of gold nanorods (Au-NRs) in acidic pH and at increased temperature. The arsenic(iii)-mediated inhibition of Au-NR oxidation is demonstrated by the red-shift of the longitudinal surface plasmon resonance (LSPR) band of Au-NRs. The novelty of our sensing strategy is the fact that it is label-free as it doesn't include any arsenic(iii) selective functionalization of Au-NRs. Moreover, this strategy can detect the arsenic(iii) content in water down to 10 ppb, which is the maximum permissible limit of the arsenic trace in drinking water according to the World Health Organization (WHO) guidelines. The effect of H2O2 in controlling the selectivity of our sensing strategy is investigated. It is found that in the absence of H2O2, the strategy is selective for arsenic(iii) with a broad dynamic response range (10-500 ppb), except for the interference from copper(ii). However, the interference of copper(ii) is efficiently eliminated by selective removal of copper(ii) from water via magnetic separation using polyethyleneimine-functionalized cobalt ferrite nanoparticles. The morphology of Au-NRs and the shift of the LSPR band during the sensing of arsenic(iii) are established by electron microscopy images and Vis-NIR absorption spectroscopy. This strategy is successfully applied for the estimation of arsenic(iii) in the real water sample and this paves the way for the implementation of our strategy for the real-time estimation of arsenic(iii) contamination levels found across prevalent drinking water sources, which are otherwise difficult to achieve with traditional sensors.

Selective removal of copper and nickel ions from synthetic process water using predispersed solvent extraction

AbstractSelective predispersed solvent extraction and the stripping of copper and nickel ions from synthetic process water containing calcium ions was investigated, and the effect of four experimental parameters on extraction efficiency was studied. The extraction process was performed in two stages. In the first stage, maximum copper extraction was targeted with nickel extraction minimized. During the second stage, nickel was extracted from the remaining copper‐free aqueous solution and optimum experimental conditions for maximum nickel recovery were determined. In order to investigate the effect of experimental parameters (extractant concentration, phase volume ratio (PVR), equilibrium pH, and calcium concentration) on the nickel extraction, response surface methodology (RSM) was used. It was found that equilibrium pH, extractant concentration, and calcium concentration were the most significant factors on nickel extraction. While the first two factors had a positive effect, the latter one negatively affected the response. In order to selectively extract copper, the optimum range for the maximum extraction of copper with minimum nickel extraction was determined, which for any level of calcium concentration is an extractant concentration of 0.2–0.3 % (w/v), phase volume ratio of 2, and equilibrium pH of 2.5. Once copper ions were selectively removed from the process water, the optimum conditions for maximum nickel concentration were determined at three levels of calcium concentrations. Stripping experiments were also carried out, and the optimum acid concentrations of 10 and 5 g/L were determined for the stripping of copper and nickel, respectively.