Copper In Chloride Solutions Research Articles

The Effect of the Concentration of Copper Ions on the Unfrozen Water Content in Bentonites Measured with the Use of DSC Method

Studies on changes of unfrozen water content in calcium bentonite from Slovakia, with various concentrations of copper ions, were carried out using the method of differential scanning calorimetry (DSC). In this study, the influence of molar concentration of copper(II) chloride solution (1 M, 0.5 M, 0.25 M, 0.1 M), used to saturate clay, was analyzed, as well as the impact of copper ions contained in bentonite and how the copper concentration affects to changes of unfrozen water content versus temperature. The results suggest that new mineral phases originate in bentonite saturated with highly concentrated solutions due to the reaction with copper(II) chloride solutions. These minerals, identified based on XRD and SEM-EDS (X-ray Diffraction and Scanning Electron Microscopy with Energy Dispersive Spectroscopy) studies, are from the atacamite group. ANOVA (Analysis of Variance) has shown a statistically significant relationship between the unfrozen water content and the molar concentration of the solution used to saturate bentonite and between the unfrozen water content and the content of copper ions in the bentonite. The analysis of multiple regression has shown that the change of unfrozen water content in copper bentonites is related to the temperature change, specific surface, and the concentration of copper ions in the clay. An empirical equation was developed to estimate the content of unfrozen water at a given negative temperature in Cu-bentonites, in which the specific surface and copper ions concentration in the bentonite are the main parameters.

Assessing the microcystins concentration through optimized protein phosphatase inhibition assay in environmental samples

Protein phosphatase (PPase) inhibition assay (PPIA) is widely used to analyze the concentration of microcystins (MCs) because it is comparatively less expensive and faster than other assays. This study aimed to optimize the PPIA by determining a suitable reaction terminator and an optimal methanol concentration in the sample. The most suitable reaction time was 90 min, with the corresponding methanol concentration in the sample being 15% or less. When p-nitrophenyl phosphate (pNPP) was used as a substrate, copper chloride solution was suitably used as a reaction terminator, and when 4-methylumbelliferyl phosphate (MUP) was used, a glycine buffer not only increased the measurement sensitivity of the reaction product but also terminated the enzymatic reaction. When PPase 1 and MUP were used as an enzyme and a substrate, respectively, the limit of quantitation for MC-leucine/arginine (LR) was 0.02 µg/L, whereas it was 0.1 µg/L when pNPP was used as a substrate. The proposed method facilitated the measurement of MC-LR concentration without additional pretreatments, such as concentration or purification; therefore, this method was suitable and feasible for the continuous monitoring of MCs in drinking water.

Effect of Schiff's bases Structure on Corrosion Inhibition Efficiency of Copper in Chloride Solutions

Effect of Schiff's bases Structure on Corrosion Inhibition Efficiency of Copper in Chloride Solutions

Removal of heavy metals by surface tailored copper ion enhanced ceramic-supported-polymeric composite nanofiltration membrane

Ceramic-supported-polymeric (CSP) composite membranes combine the benefits of robust ceramic support with tunable surface properties of polymeric active layer. The present work reports the fabrication of novel CSP composite nanofiltration membranes wherein surface ionization of the membrane active layers has been carried out by a facile process of chelating copper ions with the crosslinked polyethyleneimine polymer matrix of membrane top layer. Different concentrations of copper chloride solutions were used and their effect on membrane surface properties was investigated using EDX, XPS and AFM analyses. Performance of the membranes in removal of both cationic and anionic heavy metals, namely, Ni(II), Cd(II), Pb(II), Zn(II), As(V) and Cr(VI) from aqueous solution was studied. Excellent removal (> 95%) of all the heavy metals and optimum flux was achieved in case of GPCu0.5 membrane (surface modified with 0.5 wt% copper chloride solution). No significant decrease in flux and rejection rate of the membrane during 10 h high pressure (8 bar) operation suggested longevity of the membrane. The slow release of copper ions indicated the much-expected anti-biofouling nature of the membrane. Appreciable rejection behavior of the copper ion enhanced CSP composite membrane towards multiple heavy metals demonstrates its potential for practical water treatment application.

CuO/SnO2Nanocomposite Thin Films: Effect of Solvent and Precursor on Optical and Structural Properties

New materials nanocomposites were synthesized for the degradation of organic and inorganic pollutants. This study reviews CuO/SnO2nanocomposite thin films for their photocatalytic effect. The latter were deposited using the spray pyrolysis method, which is a simple, cheapest and rapid technique. Different concentration ratios of precursors and solvent are used. The thin films were deposited on ordinary glass substrates heated to 550∘C from solutions of copper chloride and tin chloride as precursors. The optical and structural properties of nanocomposite thin films have been demonstrated, and the equi-percentage of the precursor combination shows the good bandgap energy according to the literature. Investigations of structural properties using (SEM, EDS, XRD and RAMAN) techniques depict the good agreement photocatalytic degradation according to the surface roughness, quantities of elements and the existence of phases which will be of interest to the photocatalytic of organic and inorganic pollutants in aqueous and gas media according to the huge specific area due to the roughness and heterogeneity.

Combined method of nickel plating of cotton fabrics

To activate the surface of cotton fabrics before chemical nickel plating, it is proposed to use physical and chemical processes occurring in thin layers of solutions of copper (II) chloride under the influence of electromagnetic solar rays of the visible spectrum. It is shown that cellulose, which is the main component of the fabric, undergoes photo-oxidation in the presence of copper (II) chloride. As a result of this interaction, well-bonded copper monochloride is formed. When further processing of the fabric with phosphine gas, copper monochloride is transformed into copper and copper phosphide. Copper phosphide is a catalyst for the chemical nickel plating process. This makes it possible to obtain an electrically conductive nickel-phosphorus coating on the surface of the fabric in conventional electrolytes of chemical nickel plating. It is also found that when screening individual sections, the processes leading to the formation of copper monochloride do not occur. This allows selective metallization of the fabric.

Experimental and computational investigation of variamine blue as an inhibitor for copper in chloride solution

In this study, the corrosion behavior of copper in chloride solution in the absence and presence of variamine blue has been investigated. In this way, the electrochemical behavior of copper was studied in 3.5% NaCl and 3.5% NaCl +cM variamine blue (c = 0.025 M, 0.05 M, 0.1 M, 0.125 M) solutions under constant temperature (298 K) at a pH value of 3.5 which is about the same as that of conditioned boiler water. The pH value of the solution was adjusted by aqueous HCl and NaOH. Electrochemical techniques such as potentiodynamic polarization, open-circuit potential and electrochemical impedance spectroscopy (EIS) were used. Furthermore, anticorrosive properties of variamine blue against the Cu+ and Cu2+ metal ions are examined by computational chemistry methods. The optimum concentration of the studied inhibitors showing the highest inhibition efficiency was also evaluated at constant temperature (298 K). The inhibition efficiency (IE) was found to increase with the increase in the concentration of variamine blue. 0.125 M of variamine blue is the optimum concentration and IE% is equal to 91.29 in the mentioned concentration. The thermodynamic parameter for the adsorption process was determined. Scanning electron microscopy (SEM) observations of the copper surface confirmed the existence of such an adsorbed film. This study demonstrates that the application of variamine blue will significantly reduce the corrosion rate of copper.

Barrier performance of geosynthetic clay liners to copper (II) chloride solutions

Three needle-punched geosynthetic clay liners (GCLs) which had been manufactured with sodium (Na+) bentonite (Na-GCL) and polymerised sodium bentonites (PLS-GCL-1 and PLS-GCL-2) were permeated with 50 and 100 mM copper (II) chloride (CuCl2) solutions. The hydraulic conductivity of Na-GCL to 50 mM copper (II) chloride gradually increased to 7·7 × 10−9 m/s. In contrast, PLS-GCL-1 and PLS-GCL-2 had hydraulic conductivities of 1·5 × 10−11 and 4·2 × 10−11 m/s to 50 mM copper (II) chloride solution, respectively. Dissolution of polymers and precipitation of copper (II) (Cu2+) ions are two reasons for the low hydraulic conductivity. Metal fittings were replaced with plastic fittings, and hydraulic conductivity tests have been conducted with both solutions. The hydraulic conductivities were still low and were equal to 7·2 × 10−11 and 6·2 × 10−11 m/s with 50 and 100 mM copper (II) chloride solutions, respectively. Chemical analyses showed that cation replacements took place between bentonites and copper (II) ions. The effluents were abundant in monovalent and divalent cations which had been released from bentonites. In contrast, a considerable amount of copper (II) ions was detected in the effluents, indicating the start of the breakthrough tendency of GCLs to copper (II) ions.

Chemical Copper Plating of Cotton Fabrics by Photochemical Activation of the Surface

Activation of the surface of cotton fabrics before chemical copper plating is proposed to be carried out by applying dispersed copper particles. For this purpose, physical and chemical processes that occur in thin layers of copper chloride solutions under the influence of electromagnetic solar rays of the visible spectrum are used. Initially, copper chlorides interact with cellulose, which is the main component of the tissue, and form copper monochloride. It is shown that this interaction is stimulated by solar rays. After that, the fabric is moistened with a solution of ascorbic acid and again exposed to sunlight. Under the action of photons of solar radiation, electrons in a semiconductor acquire additional energy and restore copper to the elemental state, and the vacancies formed are filled with electrons due to the oxidation of ascorbic acid. As a result of these processes, a film is formed on the surface of the tissue containing copper particles that can catalyze chemical copper plating.

Swelling behavior of acrylamide and sodium acrylate copolymer hydrogel in aqueous solutions of copper (II) chloride with amino acids additives

Swelling of acrylamide and sodium acrylate copolymer polyelectrolyte hydrogel in aqueous Cu(II) chloride solutions with additives of proteinogenic amino acids glycine and L-histidine has been studied. Research relevance is due to the application of such systems in agrochemical products that are supposed to have high water absorption capacity in the presence of microelements ions and amino acids, which are used to prevent nutritional deficiency and make plants resistant to adverse weather conditions and diseases. Gravimetry, atomic absorption spectrometry, FTIR ATR spectroscopy and molecular absorption spectrophotometry were used. The impact of acidity (pH 3, 5 and 7) of aqueous Cu(II) chloride solutions with amino acids additives on the hydrogel swelling degree and Cu(II) ions absorption has been determined. The reasons for changes in the hydrogel swelling degree in aqueous Cu(II) chloride solutions in presence of glycine and L-histidine have been found. The main product of the crosslinked copolymer interaction with the components of 0.01 M aqueous Cu(II) chloride solution with the addition of 0.04 M glycine or L-histidine at pH 3 has been assumed to be a mixed Cu(II) ions complex with functional groups of both copolymer and amino acids.

Solution processed Cu2S/TiO2 heterojunction for visible-near infrared photodetector

A new method has been developed to grow copper (I) sulfide (Cu2S) nanoparticle (NP) inside a titanium dioxide (TiO2) thin film. This Cu2S NP growth process consists of two successive steps: ion-exchange and sulfurization process. In the beginning, Li4Ti5O12 thin film has been fabricated by a sol-gel process that contains mobile lithium-ion (Li+). This ion-conducting Li4Ti5O12 thin film has been deposited by spin coating and subsequent annealing method. In the following step, Li+ has been exchanged with Cu+ by the ion-exchange method that has been converted to Cu2S by subsequent sulfurization process. The ion-exchange has been done by immersing this Li4Ti5O12 thin film into a copper (I) chloride (CuCl) solution, whereas sulfurization has been done by dipping the Cu+ contain thin film within aqueous sodium sulfide (Na2S) solution. This process allows us to fabricate smooth and large area TiO2 thin film containing Cu2S NPs with an average particles of ∼10.5 nm. A lateral heterojunction photodetector has been fabricated based on this Cu2S-TiO2 thin film that shows a very good photoresponse in the visible-near infrared region with a highest detectivity of 1.7 × 1011jones at 830 nm.

Cyclic Voltammetry as an Electroanalytical Tool for Analysing the Reaction Mechanisms of Copper in Chloride Solution Containing Different Azole Compounds

Background: Cyclic voltammetry is widely employed in electroanalytical studies because it provides fast information about the redox potentials of the electroactive species and the influence of the medium on the redox processes. Azole compounds have been found to be effective corrosion inhibitors for copper in chloride-containing solutions. The aim of this work was to investigate in detail the influence of the addition of various azole compounds on the oxidation mechanism of copper in chloride-containing solutions, using cyclic voltammetry. Methods: The influence of thirteen azole compounds, at three different concentrations on the electrochemical/ chemical reactions of pure copper immersed in 3 wt.% NaCl solution was studied using cyclic voltammetry at different scan rates. The change of the peak current and potential with the scan rate were investigated. The possible linearity was compared with the theoretically derived mechanism. The possible reaction mechanisms were discussed based on the linearity of these parameters (peak current and potential) with the scan rate compared to theoretically derived models. Results: Both the peak current and peak potential of the copper samples immersed in chloridecontaining solutions with additions of the majority of azole compounds showed linearity with the square root of the scan rate, suggesting that copper follows the Müller-Calandra passivation model. The same behavior was also found for copper in chloride-containing solutions without additions of azole compounds. A linear variation of the peak potential with the natural logarithm of the scan rate and linear variation of the peak potential with the square root of the scan rate was observed for the copper samples immersed in chloride-containing solutions with the addition of 10 mM of 2-mercapto-1- methylimidazole, imidazole, or 2-aminobenzimidazole. This suggests that copper follows irreversible redox reactions under a diffusion controlled process. No other linear relations of the peak current and peak potential with the scan rate were found. Conclusion: Copper oxidation in chloride-containing solutions is controlled by passivation (following the Müller-Calandra passivation model) upon the addition of the majority of the selected azoles. In the minority of cases, irreversible redox reactions that follow a diffusion-controlled process were identified. None of the systems followed an adsorption-controlled process. Moreover, none of the tested systems underwent reversible redox reactions that followed a diffusion controlled process.

Sorption of Metal Ions from Aqueous Solutions by Crown Ethers

Abstract—The sorption of copper and lead ions by polymeric sorbents based on crosslinked polyacrylamide containing chemically bound or immobilized 15-crown-5 and 18-crown-6 was studied, as was the effect of various parameters on the efficiency of metal sorption from aqueous solutions. It is shown that the sorption capacity of these sorbents increases dramatically with an increase in the content of crown ethers in them from 3 to 6 wt %. When aging sorbents containing 6 wt % 15-crown-5 or 18-crown-6, in an aqueous solution of copper chloride or lead acetate, respectively, the salt concentration in the solution decreases by 3–4 orders of magnitude. When aging sorbents based on 18-crown-6 in a solution containing equivalent amounts of lead acetate or copper sulfate, the amount of absorbed copper did not exceed 5% of the amount of extracted lead, which indicates the high selectivity of such sorbents.

The Influence of Natural Saline Solutions on Dihydrate Copper Chloride Crystallization

The crystallization of salt solutions is strongly affected regarding the shape of the crystalline network by the presence of impurities, even in extremelly small quantities. This sensitivity is extremely high especially for dihydrate copper chloride (DCC) solution. The phenomenon is used for early diagnostic in medicine and for food quality assessment and named sensitive crystallization or biocrystallization. The evaluation is based on the morphology of the DCC network that crystallizes on a Petri plate containing a fine film of this solution to which a small amount of the substrate analyzed is added. For this reason, the understanding of the influence of all physico-chemical factors on the crystallization of the DCC solution is very important. To help elucidate some of these aspects, we analyzed by biocrystallization a series of 30 mineral waters from Romania, following their influence on the morphology of the DCC crystallization network. This is the first paper about biocrystallization of natural mineral waters. Following this analysis we noticed specific patterns generated by the predominant chemical composition and the total mineralization of the analyzed waters. These results can be extrapolated in the medical and agro-food field, contributing to the correct interpretation of the biocrystallisation test.

An insight into crystallization test

Crystallization test is based on the principle that, when a salt crystallizes out of an aqueous solution, the crystal growth is influenced by the presence of other substances in the solution, such as blood or plant extracts. If a mixture of copper chloride solution with a small amount of whole blood is allowed to crystallize under controlled experimental conditions, an aggregate of crystals forms. Crystallization method can be used as a diagnostic aid to provide information about the systemic conditions and general health of the patient. This study aims to study the patterns of crystallization and to further determine the efficacy of crystallization test as a screening modality in premalignant lesions and oral squamous cell carcinoma (OSCC). Fifty patients of OSCC, 50 patients of premalignant lesions, and 50 healthy individuals were selected. One drop of blood was collected from the study groups to perform crystallization using cupric chloride. Statistical analysis was performed using Chi-square test, Student's t-test (two-tailed), and analysis of variance. The different patterns of crystals formed were studied and statistically analyzed. Based on the study, it was concluded that Crystallization test can be used as an effective screening modality for detection of premalignant lesions and OSCC.

Диэлектрлі беттерде антибактериалды мысқұрамды наноқабықшаларды алу

Activation of the surface of cotton fabrics before obtaining a chemical copper film is recommended to be carried out by precipitation of dispersed copper particles. For this purpose, physical and chemical processes occurring in thin layers of copper chloride solutions under the influence of the visible spectrum of electromagnetic solar radiation are used. In this case, copper chlorides interact with cellulose, which is the main component of the fabric, forming copper monochloride. It is shown that this interaction occurs from exposure to sunlight. After that, the fabric is moistened with a solution of ascorbic acid and again exposed to solar radiation. Electrons located in a semiconductor under the influence of solar photons receive additional energy and oxidize the copper element, and the free spaces that appear in this case are filled with electrons depending on the oxidation of ascorbic acid. As a result of these processes, a shell containing copper particles that can catalyze the chemical copper is formed on the surface of the tissue.

The first observation of electrochemistry of graphene/cysteine/copper composite

A systematic characterization of electron transfer reaction involving copper amino acid complexes is an interesting task in connection with a biological activity of copper. We immobilized copper on a self-assembled monolayer of different types of cysteines grown on graphene electrode. Copper-amino acid complexes were characterized by electrochemical methods such as cyclic voltammetry. Influence of pH of electrolyte, hydrocarbon chain length of cysteine and concentration of copper chloride solution used for immobilization of copper on amino acid self-assembled monolayer/graphene composite, on electron transfer process were tested. Strong signal of copper (II) reduction was obtained in the phosphate buffer solution at pH 6.2 and no significant change was observed after change the hydrocarbon chain length on electrochemistry of graphene/cysteine/copper composite.Apart from fundamental interest, Cu2+ containing device could be interesting to study as effective copper ion sensors/catalysts on their own. One more aspect of this paper is exploitation of graphene as a supporting substrate for self-assembled monolayers.

Effect of pH on SILAR deposited CTS thin films

Copper tin sulphide thin films have been prepared using successive ionic layer adsorption and reaction method on soda lime glass substrate. In this work cationic precursor solution bath contains copper chloride, tinchloride, triethanolamine and anionic precursor solution contains thioacetamide respectively for the deposition of thin films. The prepared films were characterized by X-ray diffraction spectroscopy (XRD), UV-Vis NIR spectroscopy, scanning electron microscopy(SEM) and energy dispersive analysis(EDS). Average crystalline size calculated using Debye-Scherrer formula is 65.59nm for CTS1 and 71.17nm for CTS2. Band gap of CTS1 is 1.899ev and that of CTS2 is 1.647ev. The band gaps are suited for solar cell applications.

The Chemistry of Mordançage, a Historic Photographic Process.

Based on a 19th century method, the process known as mordançage has been used to dramatically alter black and white photographs since the 1960s. Mordançage subjects a fully developed photograph to a series of wet chemical reactions, beginning with an acidic copper(II) chloride and hydrogen peroxide bleaching solution. Different types of photographic paper, time in mordançage solution, and the concentration of hydrogen peroxide, copper(II) chloride, and acetic acid are all variables that influence the degree of emulsion lift and corresponding veils observed. We conducted experiments to explore these variables and analyzed processed prints using ImageJ to measure changes in pixel intensity and SEM-EDS for compositional analysis. Fiber-based and cotton rag papers resulted in more emulsion lift than resin-coated paper, and increased time in the mordançage solution had similar results. Quantitative analysis of the bleaching solution reveals how the process variables affect the formation of veils, and a process scheme is presented. This work provides insight into the chemical transformations involved in this artistic process.

Developing environmentally protective resource-saving technologies of radio-electronic equipment production

The compositions of the initial and spent technological solutions of the radio-electronic equipment production are investigated. Resource-saving technologies are developed and implemented: etching printed circuit boards with copper chloride solutions using countercurrent spent washing solutions and disposing of spent pickling solutions in the production of fungicides based on copper oxychloride; regeneration of halogen-organic solvents. The introduction of these technologies helps to prevent environmental pollution by toxic copper compounds (MPC of copper in fishery waters of 0.01 mg/dm3) and halogen-organic solvents