CuSO4 Aqueous Solution Research Articles

Experimental measurements and thermodynamic modeling of dissociation pressure of CO2 hydrate in sulfate solutions

Carbon capture and storage (CCS) has been a popular strategy to mitigate climate change and has attracted significant attention from both industry and academia. CO2 can be stored in the form of CO2 hydrate in deeper locations in an ocean, which makes it a potential option for CO2 sequestration. Dissolved salts in the ocean brine can significantly affect the dissociation pressure of CO2 hydrate. Sulfate salts are one of the most common salt species in the oceanic brine. Although various experimental studies have been conducted to investigate the phase behavior of CO2 hydrate in brine, few studies focus on the effect of sulfate salts on the dissociation pressure of CO2 hydrate. In this study, we build an in-house experimental setup to investigate the effect of monovalent and divalent sulfate salts on the dissociation pressure of CO2 hydrate. The dissociation pressure of CO2 hydrate in Na2SO4, K2SO4, MgSO4, and CuSO4 aqueous solutions is measured using the isochoric pressure search method at different concentrations over the temperature range of 274.36 – 282.15 K and the pressure range of 1.50 – 4.03 MPa. A hybrid methodology incorporating the Soave-Redlich-Kwong Equation of State (SRK EOS), the van der Waals-Platteeuw (vdW-P) model, and the Pitzer model is applied to predict the dissociation pressure of CO2 in sulfate solutions. In addition, the dissociation enthalpies of CO2 hydrate in these sulfate solutions are calculated using the Clausius-Clapeyron equation based on the measured dissociation points. The experimental results show that the dissociation pressure of CO2 hydrate in Na2SO4, K2SO4, and MgSO4 solutions is higher than that in pure water, and the dissociation pressure of CO2 hydrate in sulfate solutions increases with an increasing salt concentration. Conversely, CuSO4 barely affects the dissociation pressure of CO2 hydrate, which is mainly attributed to the lower molar concentration of the ions compared with the other salt solutions and the ion specificity of Cu2+. The prediction results are in alignment with the experimental data measured in this study, which proves the feasibility of the thermodynamic model in predicting the dissociation pressure of CO2 hydrate in sulfate solutions. Additionally, the calculated dissociation enthalpies of CO2 hydrate show a dependence on both temperature and salt concentration. It is also revealed that Cu2+ exhibits ion specificity in affecting the dissociation enthalpy of CO2 hydrate, likely due to its more distinct ability to impact the cage occupancy of CO2 hydrate than the other ions. These findings enhance our understanding of the impact of sulfate salts on the dissociation behavior of CO2 hydrate and offer valuable insights for CO2 sequestration.

A green and facile synthesis route of nanosize cupric oxide at room temperature

Abstract Heat, ultrasonic, microwave, and external energy are the essential conditions in the conventional preparation of nano-cupric oxide (CuO) from copper hydroxide (Cu(OH)2) precursor. In this work, CuSO4 aqueous solution (0.02 mol) was gradually added dropwise into the methanol/sodium hydroxide (NaOH/CH3OH) solution (0.04 mol) in 20 min at normal temperature and then constantly stirred the black solution for about 5 min; nano-CuO was synthesized. The as-prepared CuO had a high purity and a regular nanosize of 4–10 nm. What is more, the by-product sodium sulfate (Na2SO4) could be separated using a high-speed centrifuge, indicating that the methanol could be conveniently recycled; thereby, an environmentally friendly sustainable route of the preparation of nano-CuO was developed. In addition, the as-prepared nano-CuO was melt-compounded with polyamide 6 to produce fiber composites. The results showed that the nano-CuO was uniformly dispersed in PA6 fiber composites and presented an excellent antibacterial performance. Most importantly, the function of methanol in the dehydration process was revealed.

Bio-recovery of CuS nanoparticles from the treatment of acid mine drainage with potential photocatalytic and antibacterial applications

In the present work, CuS nanoparticles were biorecovered from a real acid mine drainage (AMD) and its photocatalytic and antibacterial activities were studied. CuS were formed by delivering biogenic H2S produced by a continuous sulfidogenic bioreactor to an off-line vessel containing the AMD. The main physico-chemical properties of CuS nanoparticles were analyzed by UV–vis spectroscopy, TEM, FE-SEM, XRD and XPS. Moreover, its photocatalytic activity on the photodegradation of organic dyes in water and its antibacterial activity against several bacterial strains were studied and compared with CuS nanoparticles synthetized from a CuSO4 aqueous solution based on the same synthesis method. CuS nanoparticles from the real AMD showed similar physico-chemical properties and photocatalytic and antibacterial activities in comparison to CuS nanoparticles formed with the copper solutions. These results open the way to recover valorous CuS nanoparticles from AMD with potential industrial applications using a metal bioremediation process based on sulfidogenic bioreactors.

Experimental and numerical analysis on electrolytic bubble group dynamics in the aluminum electrolysis process using the slotted anode

The CuSO4 aqueous solution electrolysis experiment is conducted to investigate the electrical bubble dynamics using the slotted anode to reveal the gas removal mechanism. A three-dimensional transient mathematical model coupled discrete phase model (DPM) − discrete-continuum transition model (DCTM) − volume of fluid (VOF) method is developed to track the dispersed bubble trajectory, bridge the dispersed bubble to continuous gas, and resolve the deformed bubble surface, respectively. The slotted anode decreases the bubble diameter compared with the traditional anode because the slot shortens the bubble motion distance to decrease the bubble residence time. The slot width smaller than the detached bubble diameter can limit the bubble deformation. Increasing current plays a dual role in bubble motion in the experiment: it accelerates the bubble coalescence process but decreases the bubble collision probability. The longitudinal slot is more conducive to reducing the maximum bubble coverage and increasing the bubble release frequency than the transverse slot.

Development of Ultra-Low Field Magnetic Resonance Imaging System at 1 mT

Ultra-low field (ULF) magnetic resonance imaging (MRI) is considered an innovative MRI technique that can be combined with magnetoencephalography (MEG). In this study, a 1-mT ULF-MRI system without a pre-polarization technique aiming at combining an MEG system is developed. The intensity of the static magnetic field B0 is decided considered to be 1 mT because of the limitation of the magnetic field exposed to our MEG sensor made of superconducting quantum interference devices (SQUIDs). A square-shaped (750 mm × 750 mm) B0-coil based on a Merritt-type configuration is fabricated. The inhomogeneity of B0 is less than 0.07 % in the ±125 mm area. Further, an induction coil is employed to detect the magnetic resonance signal instead of the SQUID sensors of the MEG to confirm the feasibility of realizing MRI measurement at 1 mT without the pre-polarization technique. Relaxation time measurements and MR imaging of a phantom made of a CuSO4 aqueous solution are performed. Reasonable longitudinal and transverse relaxation times are obtained, and clear shapes of the phantom are obtained using the gradient- and spin-echo pulse sequences with this ULF-MRI system. These results indicate the potential of the proposed 1-mT ULF-MRI to effectively integrate ULF-MRI and MEG systems without pre-polarization.

Versatile multimodal modality based on Brillouin light scattering and the photoacoustic effect.

Multimodal optical techniques are useful for the comprehensive characterization of material properties. In this work, we developed a new, to the best of our knowledge, multimodal technology that can simultaneously measure a subset of mechanical, optical, and acoustical properties of the sample and is based on the integration of Brillouin (Br) and photoacoustic (PA) microscopy. The proposed technique can acquire co-registered Br and PA signals from the sample. Importantly, using synergistic measurements of the speed of sound and Brillouin shift, the modality offers a new approach to quantifying the optical refractive index, which is a fundamental property of a material and is not accessible by either technique individually. As a proof of concept, we demonstrated the feasibility of integrating the two modalities and acquired the colocalized Br and time-resolved PA signals in a synthetic phantom made out of kerosene and CuSO4 aqueous solution. In addition, we measured the refractive index values of saline solutions and validated the result. Comparison with previously reported data showed a relative error of 0.3%. This further allowed us to directly quantify the longitudinal modulus of the sample with the colocalized Brillouin shift. While the scope of the current work is limited to introducing the combined Br-PA setup for the first time, we envision that this multimodal modality could open a new path for the multi-parametric analysis of material properties.

Polyampholite–Metal Complexes for Catalytic Processes

Polyampholyte–metal complexes based on polyacrylic acid; the aliphatic diamines ethylenediamine, 1,3-diaminopropane, and 1,4-diaminobutane; and Cu2+ was obtained by reacting aqueous solutions of polyampholytes and CuSO4. Using the method of simultaneous thermal analysis, it was found that the thermal degradation of the complexes occurs in three steps. The activation energy of thermal degradation of the polyampholyte–metal complexes is 22–99 kJ/mol. It was established by X-ray diffraction analysis that the products of thermal degradation of polyampholyte–metal complexes are heterogeneous systems composed of CuO and Cu2O phases, while catalysts based on them are heterogeneous systems consisting of Al2O3 and CuO phases. The size distribution of catalyst pores showed that the volume of pores with a diameter of less than 773 nm was 0.80–0.83 cm3/g, the specific surface area was 349–351 m2/g, and the predominant equivalent pore diameter was 6.2–6.3 nm. The mechanical crushing strength of catalyst pellets was found to be 7.1–7.3 MPa. In the process of CO oxidation to CO2, the catalyst began to exhibit its activity at 180–187°C; the complete conversion of CO in the oxidation reaction was achieved at 280–286°C. The performance of the obtained catalysts was 2.7–2.8 times higher than that of a reference sample.

Investigation of Cross-Linked Chitosan-Based Membranes as Potential Adsorbents for the Removal of Cu2+ Ions from Aqueous Solutions.

Rapid industrialization has led to huge amounts of organic pollutants and toxic heavy metals into aquatic environment. Among the different strategies explored, adsorption remains until the most convenient process for water remediation. In the present work, novel cross-linked chitosan-based membranes were elaborated as potential adsorbents of Cu2+ ions, using as cross-linking agent a random water-soluble copolymer P(DMAM-co-GMA) of glycidyl methacrylate (GMA) and N,N-dimethylacrylamide (DMAM). Cross-linked polymeric membranes were prepared through casting aqueous solutions of mixtures of P(DMAM-co-GMA) and chitosan hydrochloride, followed by thermal treatment at 120 °C. After deprotonation, the membranes were further explored as potential adsorbents of Cu2+ ions from aqueous CuSO4 solution. The successful complexation of copper ions with unprotonated chitosan was verified visually through the color change of the membranes and quantified through UV-vis spectroscopy. Cross-linked membranes based on unprotonated chitosan adsorb Cu2+ ions efficiently and decrease the concentration of Cu2+ ions in water to a few ppm. In addition, they can act as simple visual sensors for the detection of Cu2+ ions at low concentrations (~0.2 mM). The adsorption kinetics were well-described by a pseudo-second order and intraparticle diffusion model, while the adsorption isotherms followed the Langmuir model, revealing maximum adsorption capacities in the range of 66-130 mg/g. Finally, it was shown that the membranes can be effectively regenerated using aqueous H2SO4 solution and reused.

Natural cellulose-based Cu(II) complex: An eco-friendly nanocatalyst for Ullmann condensations at room temperature

A bio-degradable and environmentally friendly heterogeneous Cu(II) complex have been synthesized from a jute nanocellulose-based poly(amidoxime) ligand for Ullmann condensation and synthesis of flexible liquid crystals. The bio-nanocellulose surface was modified via graft co-polymerization with acrylonitrile, and the poly(acrylonitrile) was converted into a bidentate poly(amidoxime) ligand via amidoximation. Further, this ligand was treated with an aqueous solution of CuSO4 resulted in strong complex formation (NCL-Cu(II)@PA) between the amidoxime ligands and Cu(II) species. This Cu(II) complex was successfully characterized and applied to the C–O bond formation via Ullmann condensation using ultra low loading (5–50 mol ppm of Cu) of metal species. A variety of alkyl/benzyl halides and 1-phenyl-2-bromoethanone were selectively forwarded the Ullmann condensation to afford the corresponding ethers quantitatively at room temperature. The NCL-Cu(II)@PA provided excellent catalytic performance in the condensation reaction with unrivalled TON 180000 and TOF 9000 h−1. The NCL-Cu(II)@PA was easily recovered from the reaction vessel and reused for up to seven cycles without a noteworthy drop in the respective ether. Furthermore, some azobenzene core flexible liquid crystal derivatives were also synthesized using the nanocellulose-based catalyst NCL-Cu(II)@PA. According to the STM results, the lengths of the bright aromatic disc-core and the azobenzene units were 0.77 ± 0.1 nm and 1.0 ± 0.2 nm.

Synthesis, crystal structure and Hirshfeld surface analysis of catena-poly[[bis-(semicarbazide-κ2 N,O)copper(II)]-μ-sulfato-κ2 O:O'

The title polymer, [Cu(SO4)(CH5N3O)2] n , has been synthesized from aqueous solutions of CuSO4 and semicarbazide. In the crystal structure, the CuII atoms are chelated by two neutral semicarbazide mol-ecules through the oxygen atom and a nitro-gen atom of the amino group. The remaining two positions of the Jahn-Teller-distorted octa-hedral coordination sphere are occupied by oxygen atoms of two sulfate anions in the axial positions. The coordination bonds of the latter associate the polyhedra into polymeric chains running parallel to the c axis. There is a weak intra-molecular hydrogen bond between the N-H group and an oxygen atom of the SO4 2- anion. Thirteen relatively weak inter-molecular hydrogen-bonding inter-actions link the chains into a three-dimensional network. Hirshfeld surface analysis revealed that 64.7% of the inter-molecular inter-actions are from O⋯H/H⋯O contacts and 20.1% from H⋯H contacts. Other inter-actions such as N⋯H/H⋯N or C⋯H/H⋯C contribute less to the crystal packing.

Preparation and Antibacterial Activity of Nano Copper Oxide- Loaded Zeolite 10X.

Copper oxide nanosheet-loaded zeolite 10X nanocomposites (CuO-zeolite NCs) were successfully prepared by modifying zeolite 10X with CuSO4 aqueous solution. The formation of copper oxide nanosheets on the surface of zeolite 10X was observed by SEM. The thickness of CuO nanosheets was about 30–40 nm, and the width ranged from 200 nm to 300 nm. The XRD patterns showed that the new diffraction peaks of copper oxide appeared at 35.6° and 38.8°. According to the XPS results, the Cu 2p3/2 and Cu 2p1/2 peaks in CuO-zeolite NC were centered at 934.1 eV and 953.8 eV, which could be attributed to Cu(II). The EDS analysis revealed that the energy spectra of calcium gradually decreased as the copper ion concentration increased during the preparation of CuO-zeolite NCs. Meanwhile, the energy spectra of copper increased gradually, and the highest content of copper in CuO-zeolite NCs reached 22.35 wt.%. The BET surface areas of zeolite 10X and CuO-zeolite NCs were 587 and 363 m2/g, respectively, based on the N2 adsorption–desorption experiment. The antibacterial activities of CuO-zeolite NC were evaluated using Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). The antibacterial activities were related to both copper ion content in CuO-zeolite NCs and the particle size of copper oxide. The results showed that nano CuO-loaded zeolite 10X inhibited the activity of E. coli and S. aureus. CuO-zeolite NCs are expected to be further used in antifouling coating.

Reliable electrochemical setup for in situ observations with an atmospheric SEM

A novel setup for the in situ observation of electrochemical reactions in liquids through atmospheric scanning electron microscopy (SEM) is presented. The proposed liquid-phase electrochemical SEM system consists of a working electrode (WE) on an electrochemical chip and other two electrodes inserted into a liquid electrolyte; electrochemical reactions occurring at the WE are controlled precisely with an external potentiostat/galvanostat connected to the three electrodes. Copper deposition from a CuSO4 aqueous solution was conducted onto the WE, and simultaneous acquisition of nanoscale images and reliable electrochemical data was achieved with the proposed setup.

Sorption Interactions in the Hydroxyapatite–CuSO4 Aqueous Solution System

Sorption Interactions in the Hydroxyapatite–CuSO4 Aqueous Solution System

Investigation of XLPE Cable Insulation Using Electrical, Thermal and Mechanical Properties, and Aging Level Adopting Machine Learning Techniques.

Hydrothermal and chemical aging tests on a 230 kV cross-linked polyethylene (XLPE) insulation cable were carried out in the present study to evaluate the degradation and aging levels qualitatively. The samples were subjected to water aging at a temperature of 80 °C, and in an aqueous ionic solution of CuSO4 at room temperature. The diffusion coefficient results indicated that the ion migration was not at the same rate in the aging conditions. The diffusion coefficient–D–of the sample immersed in an aqueous CuSO4 solution was lower than the hydrothermally aged specimens. The hydrophobicity of aged specimens decreased considerably compared to unaged samples. The distribution of trapped charges was quantitatively characterized. The presence of shallow trap energy states were observed in unaged XLPE, whereas the deep trap sites were noticed in aged specimens. In addition, the charge trap characteristics were different for positive and negative charge deposition. Various material characterization techniques, viz. dynamic mechanical analysis (DMA), tensile, contact angle, and LIBS, were further employed on the aged and virgin specimens. The tensile behavior of the hydrothermally aged specimen was degraded due to the oxidised regions, which had formed a weak spot against the mechanical stress. Reduced glass transition temperature and increased loss tangent measurements were noticed for aged specimens over their unaged counterparts. Machine learning techniques, such as the principal component analysis (PCA) and the artificial neural network (ANN) analysis, were performed on LIBS spectral data of the samples to classify the aging mechanisms qualitatively.

Polybenzimidazole membrane for efficient copper removal from aqueous solutions

Thin films of poly(2,5‐benzimidazole) (ABPBI) polymer were prepared by the casting method, and sorption studies with aqueous CuSO4 solutions were performed. Surface interaction between Cu(II) and the membrane was studied using spectroscopic analysis (Fourier transform infrared, Raman and X‐ray photoelectron), showing a strong interaction through nitrogen groups of ABPBI and Cu(II). The best conditions for Cu(II) uptake were at pH = 5 and a soaking time of 60 min. In these conditions, the sorption isotherm was best fitted by the Langmuir equation and the maximum sorption capacity was estimated to be 1.5 mmol g−1. Due to sorption pH dependency, elution studies using hydrochloric acid solution were carried out, showing an almost complete removal of bonded Cu(II) when immersing the ABPBI membrane in the acidic solution. Surface morphology of membranes was studied using scanning electron microscopy–energy‐dispersive X‐ray spectroscopy, showing no major changes with sorption and elution experiments. These results show that ABPBI can be considered as an alternative polymer for the development of new materials for the removal of heavy metals. © 2022 Society of Industrial Chemistry.

In-situ enhanced laser absorption in aqueous transition metal salt solution enables high-quality backside wet etching of optical glass by near-infrared lasers

A laser-induced backside wet etching technique using near-infrared laser sources (N-LIBWE) has been proposed for high-quality micromachining of optical glass. Compared with conventional LIBWE using organic dye solutions with high absorption coefficients (∼104–105 cm−1) as the liquid absorbent, the transition metal salt solution used in N-LIBWE shows the absorption coefficient of only 10-1-101 cm−1. Moreover, as we proved in this study, the etching rate of N-LIBWE is independent of the absorptivity of the liquid absorbent. How the etching occurs during N-LIBWE is still controversial. Herein, interface images with a temporal resolution of 4 ns after the start of laser irradiation are captured by a stroboscopic shadowgraphy system. Afterward, the density, pressure, and temperature distribution in the solution are calculated by a physics-based two-dimensional hydrodynamic model to explain the observed interface images. We prove that the localized laser absorption is enhanced with laser irradiation because of the in-situ formation of solid substances. It is the properties of the formed solid products instead of the normal absorption coefficient of the solution that determines the final interface status. We further prove that the formed solid substances in aqueous CuSO4 solutions are primarily amorphous nanoclusters, which benefit the enhancement of laser absorption and tend to attach to the transparent substrates, resulting in the incubation effect in N-LIBWE. Our results provide systematic mechanisms explaining the N-LIBWE process, which also benefit the deep understanding of other liquid-assisted laser materials processing technologies.

SYNTHESIS OF 1,2,3-TRIAZOLO-QUINOLIZIDINES BASED ON THE QUINOLIZIDINE ALKALOID LUPININE

The modification of the quinolysin alkaloid lupinine was carried out with the intro-duction of 1,2,3-triazolyl substituents for the hydroxymethylene group in the C-1 position of the quinolysin backbone. The reaction of lupinine with methanesulfochloride in the presence of triethylamine smoothly led to lupinine methanesulfonate, whose further reaction with sodium azide in DMFA led to lupinilazide. 1,3-Dipolar [4+2]-cycloaddition of the resulting azide to alkynes produced more stable 1,2,3-triazole compounds. The interaction of lupinilazide with 2-ethinylpyridine and with alcohols containing a terminal acetylene group (propargyl alcohol, 2-methylbut-3-in -2-ol or hex-5-in -1-ol) proceeded smoothly in the DMFA medium. The reactions were carried out in the presence of an aqueous solution of CuSO4 and sodium ascorbate in DMFA and allowed the corresponding 4-substituted (1S,9aR)-1H-1,2,3-triazol-1-yl to be synthesized with good yields)methyl)octahydro-1H-quinolysins. The results of studying the structural features of synthesized compounds by 1H - and 13C - NMR spectroscopy, as well as data from the two-dimensional COSY (1H-1H) and HMQC (1H-13C) spectra are presented. The values of chemical shifts, multiplicity and integral intensity of 1H and 13C signals in one-dimensional NMR spectra are determined. In the spectra of all synthesized new quinolizi-dinotriazoles, there is a peak of the fragmentary C10H17N ion (150-151 cu), corresponding to the cleavage of the molecule by the C-10 atom of the quinolizidine backbone.

Experimental and numerical investigations on transient multiscale bubble behaviors in CuSO4 aqueous solution electrolysis cell

The present investigation demonstrates the transient multiscale bubble behaviors including the bubble homogeneous nucleation, continuous growth, disordered collision and coalescence, and disturbed detachment under the anode in the CuSO4 aqueous solution electrolysis process by experimental and numerical methods. The combined approach of the volume of fluid (VOF) method and discrete phase model (DPM) is applied to solve the macro bubbles’ surfaces and track the micro bubbles’ trajectories, respectively. The link between the macro continuous and micro dispersed bubbles is achieved by the discrete-continuum transition model (DCTM). The dumbbell and the gourd morphologies are revealed in both experiment and numerical simulation during the binary bubble collision and coalescence. The predicted maximum bubble thickness and maximum bubble coverage present reasonable matches to the experimental data. The results show that the large coalescing bubbles can extend the bubble collision period and increase the fluctuation amplitude of the bubble interface. Increasing the current will increase the bubble collision velocity and shorten the contact time before bubble coalescence, moreover, the recovery time of the oscillating bubble from coalescence to the stable state is also prolonged. Increasing inclined angles of the anode can increase the bubble velocity and decrease the bubble diameter.

Ultra-Fast and Scalable Saline Immersion Strategy Enabling Uniform Zn Nucleation and Deposition for High-Performance Zn-Ion Batteries.

Although aqueous Zn-ion batteries (ZIBs) with low cost and high safety show great potential in large-scale energy storage system, metallic Zn anode still suffers from unsatisfactory cycle stability due to unregulated growth of Zn dendrites, corrosion, and formation of various side products during electrochemical reaction. Here, an ultrafast and simple method to achieve a stable Zn anode is developed. By simply immersing a Zn plate into an aqueous solution of CuSO4 for only 10-60 s, a uniform and robust protective layer (Zn4 SO4 (OH)6 ·5H2 O/Cu2 O) is formed on commercial Zn plate (Zn/ZCO), which enables uniform electric field distribution and controllable dendrite growth, leading to a long-term cycle life of over 1400 h and high average Coulombic efficiency (CE) of 99.2% at 2.0mA cm-2 and 2.0 mAh cm-2 . These excellent characteristics of the prepared Zn anode show great potential in practical applications for high-performance aqueous Zn-ion batteries.

Review of research using analogy concept for thermal hydraulic and severe accident experiments

This paper introduces the experimental method of using mass transfer systems for heat transfer studies based on the analogy between heat and mass transfer. The copper electroplating system, composed of copper electrodes submerged in an aqueous solution of H2SO4 and CuSO4, is employed as the mass transfer system. The cupric ions transferred from anode to cathode simulate heat transfer. Applications of the experimental method are presented regarding the natural convection of the oxide pool in the IVR-ERVC (In-Vessel Retention and External Reactor Vessel Cooling) and the highly buoyant mixed convective flow conditions of the RCCS (Reactor Cavity Cooling System). The experimental method is extended to two phase flows using the reduced hydrogen at the cathode simulating the vapor bubbles. Some experiments simulating the CHF (Critical Heat Flux) problems are introduced. The paper aims at introducing the analogy experimental methodology as the preliminary quantitative experimental tools.