Copper Ions In Aqueous Solution Research Articles

Exploring the performance of Coriandrum sativum extract as an effective corrosion inhibitor for mild steel in a [formula omitted] medium, and its sustainable application in the eco-friendly removal of heavy metals

This research investigated the performance of coriander seeds, for the first time, in two critical phenomena: wastewater treatment and corrosion inhibition in acidic environments. On one hand, the aqueous extracts from Coriandrum sativum seeds (CE) were evaluated for mild steel corrosion inhibition in a 2.0 M phosphoric acid medium using several techniques such as phytochemical analysis (GC-MS), potentiodynamic polarization, electrochemical impedance spectroscopy, scanning electron microscopy (SEM-EDAX) and theoretical analyses, including DFT calculations and Molecular Dynamic Simulations, further elucidated the major chemical components. First, the phytochemical analysis has proved that CE contains heteroatoms. Second, the electrochemical results indicate that CE behaves as a mixed type inhibitor and the corrosion reaction is controlled by charge transfer process. Finally, The theoretical calculations confirmed that the active compounds of CE can be adsorbed on the Fe (1 1 0) surface through physical patterns and by sharing charges with iron to form coordinate bonds. The acquired results have shown a strong correlation between corrosion inhibition efficiency that was about 93 %, SEM-EDAX and DFT parameters. On the other hand, the study examined coriander seeds (CS) in powder form as a removal of copper ions in aqueous solutions through Atomic Absorption Spectroscopy and Inductively Coupled Plasma analysis. The parametric study was effectuated by establishing the effect of contact time, adsorbent mass, solution pH and stirring speed. The removal rate was about 79 %. Regeneration studies showed that CS could be reused for five cycles without significant loss of effectiveness. SEM-EDAX analysis has proved the studied process.

Separation trace amounts of copper ion by solid-phase extraction with carbon-based sorbent prior to flame atomic absorption spectrometry

ABSTRACT In this research, a carbon adsorbent modified with curcumin ligand was utilised in the solid-phase extraction procedure. This method was coupled with flame atomic absorption spectrometry to pre-concentrate and separate trace amounts of copper ions in aqueous solutions. Different experimental parameters, including pH, eluent type and concentration, adsorbent dose, extraction time and sample volume, were studied and optimised. The obtained optimum conditions for the proposed method were: pH of solution, 4.8; extraction time, 9 min; adsorbent dose, 0.01 g; type and concentration of eluent, 1:1 mixture of HCl and HNO3 0.5 mol L−1. Under optimal conditions, the pre-concentration factor of 400.0 and linear range values of the method were 0.031–1.875 µg/L and 12.5–750 µg/L for copper ions in the initial and final solutions, respectively. The relative standard deviation (RSD) for seven replicate detections of 0.05 µg L−1 of copper ion in initial solution was calculated as 2.2%. Furthermore, the detection limit of 0.008 µg L−1 was determined for the suggested method. In order to investigate the selectivity of modified carbon adsorbent, the influence of some interfering ions on the extraction and recovery of Cu (II) was studied. Finally, the present method was employed for the determination of copper ions in real water samples and standard alloys.

Solid-state real-time colorimetric sensing of ultra-trace copper ions using aqueous compatible chromatic probe imbued porous polymer monolithic sensor

In this work, we design an aqua-compatible and sustainable chromatic sensor for the selective detection of copper ions in aqueous solutions for application in industrial quality control and environmental analysis. The solid-state chromatic sensor is fabricated through the uniform decoration of an indigenously synthesized unique chromoionophoric probe (TMAP), i.e., (2,2′-(((1E,1′E)-thiophene-2,5-diylbis(methaneylylidene)) bis(azaneylylidene))diphenol) onto a bimodal macro-/meso‑porous polymer monolith, poly(2VP-co-DVB), i.e., poly(2vinylpyridine-co-divinylbenzene), to exploit the possibility of solid-state colorimetric ion sensing. The polymer monolith and sensor materials' topography and morphology are characterized through p-XRD, FE-SEM, XPS, EDX, TEM, SAED, TGA, FT-IR and BET/BJH analysis. The ion-sensing is accompanied by a discernible color transition from vivid yellow to subdued red, with a detection and quantification limit value of 0.20 and 0.51 μg/L for Cu2+, respectively. The sensor affirms a fast detection (≤60 s) for Cu2+, with a linear signal/colorimetric response in the concentration range of 3–100 μg/L. The parameters such as sensor dosage, chromatic receptor dose, pH, temperature, sensing kinetics and reusability are optimized for reliable and reproducible ion-sensing. The solid-state sensor reveals excellent selectivity and sensitivity for Cu2+, and its practical utility with environmental/industrial samples proves its utility as a portable sensor kit for real-time on-site analysis for ultra-trace Cu2+.

Room-temperature synthesis of nonstoichiometric copper sulfide (Cu2−xS) for sodium ion storage

Nonstoichiometric copper sulfide (Cu2−xS), which was surprisingly prepared by using excess sulfide ions to react with copper ions in aqueous solution, exhibited superior sodium ion storage performance to CuS.

Synthesis of Metakaolin Based Alkali Activated Materials as an Adsorbent at Different Na2SiO3/NaOH Ratios and Exposing Temperatures for Cu2+ Removal.

Water contamination is a major issue due to industrial releases of hazardous heavy metals. Copper ions are among the most dangerous heavy metals owing to their carcinogenicity and harmful effects on the environment and human health. Adsorption of copper ions using alkali activated materials synthesized through the polycondensation reaction of an alkali source and aluminosilicates is the most promising technique, and has a high adsorption capability owing to a large surface area and pore volume. This research focuses on the effect of the alkaline activator ratio, which is a sodium silicate to sodium hydroxide ratio. Various exposing temperatures on metakaolin based alkali activated materials on a surface structure with excellent functional properties can be used as adsorbent materials for the removal of copper ions. A variety of mix designs were created with varying sodium silicate to sodium hydroxide ratios, with a fixed sodium hydroxide molarity, metakaolin to alkali activator ratio, hydrogen peroxide, and surfactant content of 10 M, 0.8, 1.00 wt%, and 3.0 wt%, respectively. Most wastewater adsorbents need high sintering temperatures, requiring an energy-intensive and time-consuming manufacturing process. In this way, metakaolin-based alkali activated materials are adsorbent and may be produced easily by solidifying the sample at 60 °C without using much energy. The specific surface area, water absorption, microstructure, phase analysis, functional group analysis, and adsorption capability of copper ions by metakaolin based alkali activated materials as adsorbents were evaluated. The water absorption test on the samples revealed that the sodium silicate to sodium hydroxide 0.5 ratio had the highest water absorption percentage of 36.24%, superior pore size distribution, and homogeneous porosity at 60 °C, with a surface area of 24.6076 m2/g and the highest copper ion uptake of 63.726 mg/g with 95.59% copper ion removal efficiency at adsorption condition of pH = 5, a dosage of 0.15 g, 100 mg/L of the initial copper solution, the temperature of 25 °C, and contact time of 60 min. It is concluded that self-supported metakaolin based alkali activated material adsorbents synthesized at low temperatures effectively remove copper ions in aqueous solutions, making them an excellent alternative for wastewater treatment applications.

Adsorption and Desorption Behavior of Microplastics on Copper Ions in Aqueous Solution

Adsorption and Desorption Behavior of Microplastics on Copper Ions in Aqueous Solution

Photoresponsive reversible self-assembly of rod-coil amphiphiles containing spiropyran groups.

Stimuli-responsive assembly deformation is a key feature in constructing smart soft materials, which makes them versatile and autonomous. In this study, rod-coil amphiphilic compounds containing spiropyran (SP) groups were developed and synthesized to investigate their stimuli-responsive assembly in a solution system with 99% water content. In addition to photochromic phenomena, reversible light-mediated morphological alterations occurred in these molecular aggregates. Based on the different flexible chain segments of rod-coil amphiphiles, the initial assemblies underwent a dissociation-reassembly process under ultraviolet (UV) irradiation, whereupon they deformed or disassembled to assemblies. Furthermore, as the UV source was removed, the original nanostructures were gradually recovered again via the ring-closing reaction process. These compounds, interestingly, can selectively combine with copper ions to produce cross-linked co-assembled nanostructures. The copper ion complex solution of rod-coil amphiphilic compounds emitted unique bright blue fluorescence, which allowed for the specific visual identification of copper ions in aqueous solutions.

Biological Uptake of Chromium and Copper from Aqueous Systems by Penicillium notatum Biomass

Fungi have been shown to play an important role in the bioremediation of contaminated water and soils. The biosorption potential of a fungus, Penicillium notatum for chromium and copper ions in aqueous solution of their salts was investigated in this study. The effects of various parameters on the biosorption process were evaluated. These parameters which include biosorbent dose, solution pH, contact time and initial metal ion concentration were evaluated. The study showed that the maximum removal efficiency for chromium ions was recorded at pH 5 while that for copper was attained at pH 9. There was also an increase in biosorptive amount with increase in initial metal ion concentration for both ions. The equilibrium data for copper fitted better to the Langmuir isotherm compared to the Freundlich isotherm while that of chromium had a better fit for Freundlich isotherm compared to the Langmuir model. The maximum biosorption capacity, Qo, for chromium and copper obtained from the Langmuir plots are 23.15 and 4.02 (mg/g) respectively. This shows that Penicillium notatum biomass has the ability to remove these metal ions from contaminated waters under suitable conditions.

Polyethyleneimine-modified lobster shell biochar for the efficient removal of copper ions in aqueous solution: Response surface method optimization and adsorption mechanism

In this study, lobster shells were used as the biomass raw material, and were modified by cross-linking with KOH and polyethyleneimine to obtain amine-functionalized biochar (PBC) for the removal of Cu2+ in polluted water bodies. The biochar was characterized before and after modification. The BoxBehnken design response surface methodology was used to optimize the experimental conditions and to investigate the effects of initial concentration, pH and dosage on Cu2+ removal. Its adsorption performance was evaluated. The results show that PBC has a greater Cu2+ adsorption capacity than other biochars, and the maximum adsorption capacity reached 491.68 mg·g−1. This is mainly because the main inorganic component of lobster shell biochar is CaCO3. polyethyleneimine modification makes a new active functional group -NH2 on the surface of the original biochar (BC) and increases the number of nitrogen-containing groups such as C-N and -NH. The initial concentration had the greatest effect on the removal of Cu2+, and the interaction of pH and initial concentration was the most significant interaction factor throughout the adsorption process. The adsorption of Cu2+ by BC and PBC followed the pseudo-second-order, fractal-like pseudo-first-order, fractal-like pseudo-second-order kinetic equation and Langmuir isothermal adsorption model for chemisorption on a single molecular layer. Cu2+ is mainly removed by complexation, ion exchange, coprecipitation and physical adsorption. Carbonate and nitrogen-containing groups on the surface of PBC are the main adsorption sites for Cu2+. Furthermore, the adsorbent has excellent reusability and practical application potential.

A cyclodextrin-based turn-off fluorescent probe for naked-eye detection of copper ions in aqueous solution

A novel fluorescent probe L consisting of β-Cyclodextrin (β-CD) and thiosemicarbazide moieties was designed for copper ions detection. Apparent fluorescence quenching of probe L in Tris-HCl（pH = 7.4）solution was observed only in the presence of Cu2+, among other interfering ions. The present probe L was 1:1 complexed with Cu2+ and the detection limit of probe L was calculated to be 1.37 μM. The results demonstrate that the probe L may provide a convenient method for visual detection of Cu2+ in the environmental and biological systems.

PbS/graphene hybrid nanostructures coated glassy carbon electrode for the electrochemical sensing of copper ions in aqueous solution.

In this research, we have studied the electrochemical sensing of Cu(II) ions in aqueous solution using PbS/Graphene composite nanostructure coated glassy carbon electrode (GCE). The SEM-EDAX analysis revealed that the lead sulphide nanocrystals are homogeneously embedded on the graphene nanosheets with an uniform particle size of 100nm, and the elements presents 92.32% and Lead content of 5.45% and Sulfur content of 0.91%. Raman spectra exhibits G with respect to the E2g sp2 hybridized C-C and D band with respect to the A1g mode in the disordered edge region of the GNS. The composite nanostructure coated GCE (PbS/Graphene/GCE) was prepared and its performance in the existence of metal ions such us Cd(II),Pb(II), Mg(II), Cu(II) and Ni(II) was studied using the current voltage curves in double distilled water within the scan rates of 25 to 300mVs-1. The PbS/Graphene coated carbon electrode exhibited the higher anodic and cathodic peak current for copper solution than the other metal ions studied, which various linearly proportional to concentration. The electrochemical sensing characteristics PbS/GNS/GCE was found to be significant towards detecting Cu2+ ion within the concentration range of 1×10-4 to 1×10-8M, with a lowest sensing detection limit of 1×10-8M.

Magnetic field intensified electrodeposition of low-concentration copper ions in aqueous solution

A large amount of low-concentration copper ion solution is generated during the recycling process of lithium-ion batteries. Low efficiency and poor selectivity for electrodeposition recovery of low-concentration copper ion solution due to slow ion migration rate. To increase the ion transfer rate of the diffusion layer, the low-concentration copper ion solution was pre-magnetized or in-situ magnetized for electrodeposition. Results indicated that the pre-magnetized electrolyte or magnetic field assisted-electrodeposition process could change the hydrogen bond structure, increase the solution viscosity, reduce the interface transfer resistance (Rct) and the transfer coefficient of copper ions in the diffusion layer, while reduce the radius of hydrated particles, the symmetry of the hydrated ion structure, and the activation energy of the reaction. As a result, the electrolysis efficiency increased from 22.1 to 32.3% for 0.01 mol/L CuSO4 solution, and from 92.3 to 98.1% for 0.1 mol/L CuSO4 solution after pre-magnetization.

Surfactant-Modulated a Highly Sensitive Fluorescent Probe of Fully Conjugated Covalent Organic Nanosheets for Detecting Copper Ions in Aqueous Solution.

Efficient detection of aqueous copper ions is of high significance for environmental and human health, since copper is involved in potent redox activity in physiological and pathological processes. Covalent organic frameworks (COFs) have shown advantages in efficient capturing and detecting of copper ions due to their large surface area, robust chemical stability, and high sensitivity, but most of them are hydrophobic, leading to the limitation in sensing copper ions in aqueous media. Herein, the design and synthesis of an sp2 -carbon conjugated COF (sp2 -TPE-COF) are reported with surfactant-assisted water dispersion for detecting traces of copper ions based on the photo-induced electron transfer (PET) mechanism. Importantly, the olefin-linked conjugated backbone of sp2 -TPE-COF works as a signal amplified transducer for metal ion sensing. Notably, it is found that a surfactant-assisted strategy can greatly enhance COF's dispersion in aqueous solution and finely modulate their sensitivity with a significantly improved KSV to 15.15 × 104 m-1 in SDBS (sodium dodecyl benzene sulfonate) solution, the value of which is larger than that of a majority of COF/MOF based sensors for copper ions. This research demonstrates the promise of surfactant modulated fully π-conjugated COFs for sensing applications.

Novel Schiff base functionalized 80-μm tilted fiber Bragg grating chemosensor for copper(II) ion detection

A novel Schiff base functionalized tilted fiber Bragg grating (TFBG) is developed for the rapid detection of Copper ions in aqueous solutions. Notably, the proposed TFBG was inscribed in a commercial 80 μm diameter single-mode fiber that has a stronger evanescent field and functionalized with Schiff base that has a strong affinity with copper(II) ions. The findings indicate that the 80-μm TFBG is more superior to the TFBG inscribed in the 125-μm diameter standard optical fiber in terms of higher sensitivity, a lower limit of detection, and less susceptibility to refractive index noise. Furthermore, the proposed sensor is a silica glass-based optical component that can be reused multiple times via chemical stripping followed by a functionalization process. The results show that there is no sign of alteration and degradation in its optical spectrum after 24 times of chemical stripping processes.

The use of zeolite-based geopolymers as adsorbent for copper removal from aqueous media.

Copper has been proven to have hazardous effects on human beings depending on its concentration levels. Recently, there has been a growing interest in developing geopolymers using local industrial minerals and by-products. However, research on the adsorption of heavy metals by geopolymer based on mordenite-rich tuffs is still limited. The geopolymer adsorbents have been synthesized using natural Ecuadorian zeolite-rich tuffs containing quartz, mordenite calcite and amorphous content with 20.8%, 28.5%, 4.2% and 46.4%, respectively. The geopolymers showed a maximum compressive strength of 26.86 MPa for 28 d of curing time. In the present study, an Ecuadorian zeolite-based geopolymer's removal capacity on copper ions in aqueous solutions, varying concentration and contact time were tested. Kinetic models were developed using pseudo first-order, pseudo second-order and the Elovich model. The adsorption data, using Cu2+ concentrations from 20 to 160 ppm, at 25°C were described by the Langmuir and Freundlich isotherms. Linear coefficient of determination (R2) results show that the Langmuir model fits the best. The attained adsorption capacity of 52.63 mg g−1 demonstrates the low-cost geopolymer's effectiveness for this study and its competitiveness compared with other studies. Adsorption kinetics follows the pseudo second-order kinetics model at the lower initial concentration of Cu2+.

Cyclic voltammetry to study kinetics of blast furnace slag and cerium dioxide modified electrode

Abstract The use of a voltammetric sensor to measure hazardous elements has gotten a lot of coverage. The electrochemical sensor in this study was modified with cerium dioxide (CeO2) and blast furnace slag (BFS), which opens up new possibilities for improving the electrocatalytic properties of the fabricated sensor. In general chemical kinetics or mass transport can restrict the reactions involved in electrochemical detection. The prepared electrodes were tested against potassium ferricyanide, K3Fe(CN)6 solution by cyclic voltammetry. Cyclic voltammetry was used to investigate the chemical reactions involve during redox process. The electron transfer kinetics, chemical rate constant, and diffusion characteristics of reactions can all be extracted using this method. Further this sensor was applied in the detection of lead and copper ions in aqueous solution. The results show that the redox reaction is a one-electron transfer mechanism with high selectivity and sensitivity. The value of transfer coefficient (α) for the electrode reaction was calculated as 0.61. Also the calculated heterogeneous electron transfer rate constant (Ks) of the modified electrode was 2.41.

Some peculiarities of the kinetics of interaction of cationic hydrogels based on copolymers of vinyl esters of monoethanolamine and ethylene glycol with copper ions

Over the past few decades, formation of polymer hydrogels complexes with metal ions, including transition ones, attracts the steady attention of researchers. The relevance of such study is due to the fact that the kinetics of swelling and contraction of hydrogels in various media has been studied in many works, however, this question remains insufficiently studied. Cationic hydrogels based on copolymer of vinyl ethers of monoethanolamine (VEMEA) and ethylene glycol (VEEG) as the study subject in the present work have been used. The kinetics of interaction cationic hydrogels based on copolymer of vinyl ethers of monoethanolamine and ethylene glycol with copper ions in aqueous solutions has been studied. It was shown that swelling behavior such hydrogel in this process is characterized two stages. At the initial stages of the interaction of the gel with the copper salt solution, the interaction in question is determined mainly by the displacement of water from the swollen mesh, due to the difference in osmotic pressures inside and outside the sample. At this stage, the kinetics of the gel contraction is described by the same laws as for polyelectrolyte hydrogel in the alkali metal solution. At the second stage, the network charge density increases due to the formation of a complex, and the degree of the gel swelling begins to increase with time. On the basis of the results obtained, it can be assumed that in systems of this kind, metastable states with differences in character from truly equilibrium states, persisting for a long time, can be formed.

Efficient removal of lead and copper ions in aqueous solution by glutamic acid-functionalized SBA-15

Efficient removal of lead and copper ions in aqueous solution by glutamic acid-functionalized SBA-15

Removal of copper ions from wastewater via adsorption on modified hematite (α-Fe2O3) iron oxide coated sand

In this study, we improved the surface quality of synthetic hematite (α-Fe2O3) iron oxide coated sand (HIOCS) and its adsorption and desorption capabilities for copper ions in aqueous solutions, and we evaluated the iron oxide content on the sand surface. We prepared three different control pH (1, 5, and 10) solutions using FeCl3, to obtain the above results. In addition, we used X-ray diffraction, Fourier-transform infrared spectroscopy, scanning electron microscopy, and EDX, analyses were performed for characterization of analysis to characterize the surface morphologies of the coated layer and observe copper ion adsorption on the coated sand surfaces. Batch experiments were conducted to assess copper ion adsorption under specific parameters, such as the influence of time, dosage, pH, and initial copper concentration. Adsorption isotherms and kinetics models were used to fit the experimental data at various temperatures (287, 297, and 307 K), and different desorption media were studied to assess copper ion regeneration from hematite (α-Fe2O3) iron oxide coated sand (HIOCS). We observed high intensity, pure hematite (α-Fe2O3) crystal peaks, and iron content (105.3 mg/g) on the sand coated at a pH of 1, and copper ion removal efficiency was more effective (94%) at lower pH, compared to the sand coated at a pH 5 and 10 (81% and 84%, respectively) at constant parameters (pH of 6, dose of 4 g/L, temperature of 297 K, 30 mg/L of Cu2+ concentration, and contact time of 180 min). The Langmuir isotherms model (R2 = 0.991) and pseudo-second-order kinetic models (R2 = 0.978) were found to correlate better than the Freundlich isotherm model (R2 = 0.966), or the pseudo-first-order kinetics model (R2 = 0.965). We achieved the highest Cu2+ adsorption of qm = 3.93 mg/g, as obtained from the Langmuir isotherms. We also observed that acidic (HCl and H2SO4) solutions were the best desorption media for copper ions on the surface of hematite (α-Fe2O3) iron oxide coated sand (HIOCS). Thus, this study found that copper ions can be removed through an environmentally friendly process using low-cost hematite (α-Fe2O3) iron oxide coated sand (HIOCS), under suitable conditions.

Mutual influence of cupric cations and several anions in anatase and rutile TiO2 photocatalysis.

Copper ions in aqueous solution are known to promote organic oxidation in semiconductor photocatalysis, but the counter anions seem to be important as well. In this work, the performance of Cu(ClO4)2 in presence of several anions in sodium forms (F-, Cl-, ClO4-, NO3-, and SO42-) has been examined. Phenol oxidation in aqueous solution (pH 4) under UV light was used as model reaction and TiO2 in the forms of anatase (AT) and rutile (RT) as photocatalysts. On the addition of 0.1-5mM Cu2+, the reactions on AT and RT all increased. On the addition of 1mM anions, reactions on AT increased by F-and SO42-, but reactions on RT all decreased. In presence of 3mM Cu2+, however, reactions on AT and RT all decreased by 1mM anions except NO3-. Such anion effects were also observed for H2 production on AT and RT in presence of Cu2+ and 10% methanol. A possible mechanism for the positive and negative anion effects is discussed. This work indicates that the formation of a Cu(II)/Cu(I) complex with anions weakens the positive effect of copper ions on organic oxidation in TiO2 photocatalysis.