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The Electroseparation of zinc(II) from a solution of uranium(III) generated by the reduction of uranium(IV) triflate (U(OTf)4) with zinc amalgam (Zn(Hg)) was studied to establish a convenient route to the precursors of organic uranium(III) compounds. Specifically, the electrode reactions of U(OTf)4 in N,N-dimethylformamide on mercury (Hg) and Zn(Hg) electrodes were probed by voltammetry and bulk electrolysis measurements. The voltammograms recorded on the former electrode showed three cathodic waves assigned to the reduction of a uranium(IV) solvate complex (− 1.48 V), the reduction of [U(OTf)]3+ (− 1.81 V), and uranium amalgamation (− 2.65 V). On the latter electrode, the first cathodic wave was masked, as it was located at the potential of zinc amalgamation. Bulk electrolysis experiments revealed that for both Hg and Zn(Hg), the working electrode potential featured a plateau around − 2.3 V, which was not observed in the corresponding voltammograms and was related to the degradation of uranium(III) based on spectroscopic observations. The Electroseparation of zinc(II) from the uranium(III) solution on Zn(Hg) was successfully (highest coulombic efficiency = 0.81, final zinc(II) separation ratio = 93.4%) carried out after the reduction of U(OTf)4 by Zn(Hg). [ABSTRACT FROM AUTHOR]

Zinc electrodeposition is currently a hot topic because of its widespread use in rechargeable zinc‐air batteries. However, Zn deposition has received little attention in organic solvents with much higher ionic conductivity and current efficiency. In this study, a Zn‐betaine complex is synthesized by using ZnO and betainium bis[(trifluoromethyl)sulfonyl]imide and its electrochemical behavior for six organic solvents and electrodeposited morphology are studied. Acetonitrile allowed dendrite‐free Zn electrodeposition at room temperature with current efficiencies of up to 86 %. From acetonitrile solutions in which Zn, Pb, and Cu complexes are dissolved in high concentrations, Zn and Pb/Cu are efficiently separated electrolytically under potentiostatic control, allowing the purification of solutions prepared directly from natural ores. Additionally, a highly flexible Zn anode with excellent kinetics is obtained by using a carbon fabric substrate. A rechargeable zinc‐air battery with these electrodes shows an open‐circuit voltage of 1.63 V, is stable for at least 75 cycles at 0.5 mA cm−2 or 33 cycles at 20 mA cm−2, and allows intermediate cycling at 100 mA cm−2. [ABSTRACT FROM AUTHOR]

Reliable, easy, cost-effective and reproducible ways of extracting microplastics (MP) from environmental samples remain important requirements for MP research. In this context, electrostatic separation is a new proposition, especially for extracting MP from mineral-rich samples and large sample volumes. However, there is little research evaluating the reliability of the technique. This study has evaluated the effectiveness of the Korona-Walzen-Scheider (KWS) system; a small-scale version of larger machines designed to sort recycling materials. Recovery rates of a variety of sizes of MP, spiked in beach sediments, were found to be highly dependent on the MP size. MP ≥ 2 mm achieved 99 – 100% recovery (with the exception of fibers: ∼80%), MP of 63–450 μm achieved ∼60–95% recovery and MP of 20 μm achieved ∼45% recovery. For particle-based analysis, additional density separation is still inevitable for the analysis of small MP after KWS separation and further reduces the overall recovery rates. Mass reduction rates of beach and commercial reference sand greatly differed, 93 and 17%, respectively. Mineral analysis using SEM-EDX suggested that lower reduction rates found in commercial sand was due to high presence of small ( 450 μm, electrostatic separation is a reliable and fast approach for MP extraction from the environment.

Numerous studies on microplastics (MPs; Ø < 5 mm) in the aquatic environment have been published, but knowledge about the occurrence and ecological risks of MPs is limited. This is in part because current data on the distribution of MPs are comparable only to a limited extent, due to the many different methods of investigation. In addition, sample preparation is often difficult such that standard procedures are lacking. The aim of this work was to simplify the preparation of different kinds of MP samples. Our method makes use of the electrostatic behavior of plastic particles to facilitate their separation from sample matter, with up to 99% of the original sample mass removed without any loss of MPs. To determine the efficacy of this approach, four different materials (quartz sand, freshwater suspended particulate matter, freshwater sediment, and beach sand) were spiked with MPs (size: 0.063–5 mm from the seven most common types of plastics, one bioplastic type, polyethylene fibers, and tire wear. A modified electrostatic metal/plastic separator was used to reduce the sample mass and concentrate the plastics based on their physical separation. The recovery achieved with this method was as high as nearly 100% for each type of material. The method was then tested on plastic particles of different shapes and types isolated from the Rhine River. These were successfully electroseparated from the four materials, which demonstrated the utility of this method. Its advantages include the simplified handling and preparation of different field samples as well as a much shorter processing time, because after the last separation step there is hardly any biological material remaining in the sample fraction. [ABSTRACT FROM AUTHOR]

Separation process of LYZ by electrodialysis with ultrafiltration membrane. [Display omitted] • Separation lysozyme from ovalbumine with an EDUF process was demonstrated for the first time. • Effects of EDUF process parameters on the separation performance were investigated. • The purity of lysozyme isolated by EDUF could reach 100%. • The maximum yield of recovered LYZ by EDUF process was 32.2%. Lysozyme (LYZ) is a vital bioactive protein due to its chemical stability, non-toxicity, and biological functions including antibacterial, antiviral and anti-inflammatory activities. LYZ's separation and purification processes are essential for its applications in the food, pharmaceutical and some other fields. Electrodialysis with ultrafiltration membrane (EDUF) is a recently developed technique that has been proven to have a high selectivity in fractionating natural biologically active compounds. This study was conducted to isolate and purify LYZ from a model solution containing ovalbumin (OVA) and LYZ using an EDUF process, and to evaluate the effects of the operational parameters on its separation performances. Results showed that an excessive or inadequate applied voltage or solution flow rate was not conducive to the migration of LYZ. Additionally, the volume ratio of feed to permeate solution was inversely related to the amount of LYZ recovered. Under the most favorable conditions, with a voltage of 5 V, solution flow rate of 50 mL/min and volume ratio of 1:1.5, LYZ was recovered with a total yield of 32.2% and a purity of 100% after 240 min of running, with a relative energy consumption of 1.52 kW•h/g. This study demonstrated that LYZ could be successfully separated from the mixtures of OVA and LYZ by an EDUF process. EDUF technology provides an effective and innovative method for the active protein separation in the egg product-related industry. [ABSTRACT FROM AUTHOR]

[Display omitted] • Application of Tafel and LP to judge the kinetic properties of Eu and Gd on liquid Pb and LBE cathodes. • The effects of PE, GA, and PPE on separation factor, extraction efficiency, and crystal size were investigated and compared. • The reduction mechanism of Eu from Gd on liquid LBE alloy cathodes was systematically investigated. • The separation factors SF Gd/Eu of Gd/Eu and the extraction efficiency of Gd reached up to 759 and 99.1 %, respectively. The highly effective separation of two adjacent rare earth is significant to the rare earth and nuclear industries. This paper investigates the highly effective separation of Gd over Eu using liquid lead–bismuth eutectic (LBE) alloy cathode in molten LiCl-KCl-EuCl 3 -GdCl 3 by pulse potential electrolysis (PPE). Underpotential deposition of Eu and Gd is observed on the LBE alloy, with a depolarization value far greater than that of the liquid Pb electrode. Furthermore, the higher exchange current density and the lower activation energy of the electrode reaction indicate that the LBE alloy cathode has higher kinetic performance than the liquid Pb. Then, the practical electro-separation in LiCl-KCl-EuCl 3 -GdCl 3 systems is carried out by applying different electrolysis technology. The effects of varying electrolysis methods and parameters on separation factor (SF), extraction efficiency, cathode product morphology, and crystal size are studied and compared. The results show that both the extraction efficiency and the separation factor obtained by the PPE are the largest. The calculated extraction efficiency of Gd and the actual separation factor SF Gd/Eu of Gd/Eu could be up to 99.1 % and 759, respectively. [ABSTRACT FROM AUTHOR]

• Zn is directly separated from ZnS in choline chloride-urea-malonic acid (ChCl-urea-MA) deep eutectic solvent. • This process achieves the current efficiency of 86.5 % with the energy consumption of 2621.8 kW·h·t−1. • MA causes 0.13 mol·L-1 ZnS being dissolved to form stable MA-based ligands. • This study initiatively simplifies Zn separation from ZnS in green solution with hazardous waste minimization. Zinc sulfide (ZnS), one of the main ingredients of zinc ore and emerging materials, partly processes environmental risk. Deep eutectic solvents (DESs) are green solvents to efficiently separate metals with less emission. In this study, a novel route for direct electroseparation of Zn from ZnS in eco-friendly choline chloride-urea DES with the addition of malonic acid (MA) is studied for the first time. The role of MA and the reduction behavior of Zn(II) are systematically analyzed by cyclic voltammetry. The reduction of Zn(II) is quasi-reversible and follows one-step two-electron transfer process. Pure Zn with nanostructure is obtained with the current efficiency of 86.5 % and energy consumption of 2621.8 kW·h·t−1 at the optimized parameters of 10 mA·cm−2, 353 K and 100 mM·L-1 ZnS. Mechanisms analyses indicate that in the presence of 60 mM·L-1 MA, besides [ZnCl− 3 ]- and [ZnCl− 5 ]3-, some ZnS are dissolved to form stable [Zn(MA)2-Cl− 2 ]4-, [Zn(MA)2-Cl-]3- and other MA based ligands, which causes a higher Zn ion solubility of 0.13 mol·L-1 and may promote the subsequent electroseparation of ZnS. Results from this study are expected to propose a simplified route to directly separate Zn from ZnS without oxidation pretreatment to achieve hazardous waste minimization. [ABSTRACT FROM AUTHOR]

Abstract: The electrochemical behaviour and extraction efficiency of DyCl3 and GdCl3 solutions were studied by cyclic voltammetry, square wave voltammetry and open-circuit chronopotentiometry in the eutectic LiCl-KCl at 773K using inert and reactive electrodes, i.e. W and Mg, respectively. On W and Mg electrodes, Dy(III) ions are reduced to metallic dysprosium through two consecutive steps. The selective electrodepositing of dysprosium in a form of Mg-Dy alloys can be easier than that in a pure metallic form, without reduction of the extraction yield. Potentiostatic electrolysis experiments were performed to extract Dy from GdCl3 and DyCl3 mixtures at magnesium electrodes. XRD patterns of deposit indicated that Mg3Dy phase was formed. Scanning electron microscope (SEM) images with Energy dispersive X-ray Spectroscopy (EDS) showed the grain size was refined with a greater content of Dy in alloys [Copyright &y& Elsevier]

Abstract: This paper deals with the problem of dielectric liquids purification. The separation process of mechanical impurities from dielectric liquids in an electric field is analyzed and an experimentally validated mathematical model is proposed for the electroseparation process. The main objective is to find a relationship to describe the kinetics of particles electroseparation, solving the problem of establishing a relationship of dependency between initial concentration and final concentration with time, and determining the electroseparation time depending on particles and liquid dielectric properties. [Copyright &y& Elsevier]

A study of the electrochemistry of uranium in LiF–BeF2 system important for molten salt reactor concept was conducted at W and Ni electrodes. Cyclic voltammetry and chronopotentiometry methods were used. Two-step reduction mechanism for U4+ ions involving one electron exchange in soluble/soluble U4+/U3+ system and three electron exchange in the second step were found on W electrode. Both processes were identified as reversible and diffusion-controlled. Based on voltammetric and chronopotentiometric measurements, the diffusion coefficient of U4+ ions at 813 K was calculated: D(U4+) = 1.26 × 10−6 cm2 s−1 and D(U4+) = 1.28 × 10−6 cm2 s−1, respectively. Formation of U–Ni alloys was observed on Ni electrode. [ABSTRACT FROM AUTHOR]

Abstract: The aim of the present work was to study the effect of solution flow velocity and electric field strength applied to an electrodialysis with ultrafiltration membrane (EDUF) cell on chitosan oligomer electromigration kinetics and on chitosan oligomer mixture fractionation. It was shown that the effect of solution flow velocity was not significant, while the electric field strength showed a significant effect on each chitosan oligomer electromigration rate. The effect of the electric field strength was also significant on the separation possibility of the studied oligomers. It was shown that by using electric field strength of 2.5V/cm, it was possible to obtain a solution composed only of the dimer and trimer until an operating time of 2h. By increasing the electric field up to 5 and 10V/cm, it was no more possible to separate the chitosan oligomers. Chitosan oligomer transport numbers were measured. It was found that they contribute to about 7% of total electric current carrying, while about 93% of the total electric current could be carried by the electrolytes. The system performance was also evaluated through electric field intensity measurement and membrane integrity evaluation. It was found that the membranes kept their integrity and no significant fouling was detected. EDUF appeared consequently as a very interesting and innovative technology for the separation at a large scale of oligosaccharide. [Copyright &y& Elsevier]

Abstract: Interest in chitosan oligomers of low molecular weights is growing fast because of their potential use as bioactive ingredients. In the present study, the effect of pH and electrodialysis with ultrafiltration membrane (EDUF) cell configuration was studied on electromigration of chitosan oligomers (dimer, trimer and tetramer) to demonstrate the potential selective and specific separation of the three oligomers from each others. It was shown that cell configuration influenced the possibility of separation of the oligomers since oligomer migration and separation was observed only in configuration 1 (anode–AEM1–UFM–AEM2–cathode). Furthermore, chitosan oligomer electromigration decreased by increasing the pH of the medium. Hence, the dimer showed the highest electromigration rate at all pH values, followed by trimer, and then by tetramer. It was shown that it was possible to separate dimer mixed with trimer at pH 6 or only the dimer at pH 7 according to the processing time. There was no electromigration at pH 8 and 9. Up to now, only analytical methods were known to separate dimer, trimer and tetramer. Consequently, it was a real challenge to separate, on a potential large-scale technology such as EDUF, the dimer from the trimer and tetramer since they have very close molecular weights. [Copyright &y& Elsevier]

Optimization of reduction potential for electroseparation was studied for the recovery of gold, copper, and lead from acidic solution. A linear sweep voltammetric method enabled us to determine characteristic reduction potentials for each metal and the kinetics of the metal deposition indicated by current-voltage curves. In order to precipitate the metal species sequentially, reduction potentials were examined for the individual and mixed solutions of Au(III), Cu(II), and Pb(II). The three metals were reasonably well isolated from the mixed solutions such as Cu(II)/ Pb(II) and Au(III)/Cu(II)/Pb(II) in the order of the corresponding reduction potentials, in particular, the mass transfer controlled reduction potentials, obtained from linear sweep voltammetry (LSV) measurement. [ABSTRACT FROM AUTHOR]

A simple, scalable method for purification of plasmid DNA is described. Plasmid DNA was released from Escherichia coli JM109 by lysis (1% SDS, 0.2 M NaOH). Then a neutralization solution (3 M sodium acetate buffer, pH 4.8) was added to precipitate genomic DNA and protein. After the clarification of the lysate, the supernatant was placed in a multicompartment electrolyser separated by ultrafilter membranes to remove the remaining contamination (RNA, genomic DNA and protein). A recovery of 75%±2% of total plasmid DNA was obtained after 60 min electrophoresis with a field strength of 8 V cm-1 using cells at 30 g l-1 (quantified by dry cell weight). Genomic DNA, RNA and protein were undetectable in the purified plasmid DNA solution. [ABSTRACT FROM AUTHOR]

• The electroseparation of uranium from lanthanides on a liquid Ga cathode was studied. • The separation factor on Ga cathode is 1-2 orders of magnitude higher than that on Cd. • Current pulse electrolysis method shows potential advantages on U/Lns separation. The aim of this work is to explore the electroseparation of uranium from lanthanides (La, Ce, Pr, Nd and Sm) on a liquid gallium electrode. Cyclic voltammetric results showed that in multi-component melt systems (U/Nd, U/La-Ce-Nd, and U/La-Ce-Pr-Nd-Sm), the reduction potentials of each lanthanides on the Ga cathode are identical and cannot be distinguished and resolved. The peak potential differences between the lanthanides and uranium are all at about 250 mV. The practical electroseparations in U/Nd, U/La-Ce-Nd and U/La-Ce-Pr-Nd-Sm systems were carried out by applying different electrochemical techniques as galvanostatic, potentiostatic and current pulse electrolysis. After electrolysis, the ICP-AES technique was used to determine the composition of molten salt and alloy deposits, and the actual separations factor of U over lanthanides in these multi-component systems were calculated and compared. The results showed that the separation factors of U/La and U/Sm can be both up to 1000, whilst that of U/Nd is relatively low with an average value of about 350. In addition, the separation factor obtained by the current pulse electrolysis is larger than that of galvanostatic and potentiostatic method, and the potentiostatic electrolysis provides the lowest one. [ABSTRACT FROM AUTHOR]

The beneficiation of kyanite ores by a new dry technology is studied. Compared to the flotation method, the method reduces energy consumption from 300 – 400 to 15 – 25 kWh/ton. Dry electroseparation has made it possible to obtain concentrates with an Al 2O 3 content of 59 – 60% while also producing pure quartz (“tailings”). [ABSTRACT FROM AUTHOR]

Abstract: A variable-volume sample injector design is presented and evaluated for performing sample introduction protocols for carrying out miniaturised isotachophoresis (ITP) separations. The microdevice design features a wide bore sample loop channel connected to a narrower bore separation channel via a short injection channel angled at 45°. An additional side arm channel located at the injection point enabled a range of injection strategies, using a gravity-fed system, to be implemented and assessed. A model analyte was used to demonstrate the versatility of the injector design for low and high sample loading regimes suitable for concentrated and dilute sample solutions, respectively. [Copyright &y& Elsevier]