Separation of Ho3+ in Static Magnetic Field

Abstract The rare earths elements (REE) belong to the group of critical metals and they are achieving more and more interest due to their special properties. However, there occur some problems connected with their production. The most difficult phase is separation of REE. It includes a necessity to intensify currently applied processes and looking for new solutions. The present work introduces an idea to use differences in physical properties of the REE ions to get them separated. In the experimental part of the work some efforts were undertaken to analyse results presenting changes of holmium ions concentration under an influence of the magnetic field gradient. There was determined the gradient of magnetic field and concentration of Ho3+ ions depending on initial concentration of the solution and time. A simulation of changing the concentration of holmium ions in the solution under an influence of the magnetic field gradient was performed to compare the mathematical model with the obtained results

Catalytic Properties of Electroless Nickel-Based Coatings Modified by the Magnetic Field

In this work the nickel-based coatings were obtained by electroless catalytic deposition on light-hardened resins dedicated for 3D printing by SLA method. The effect of external magnetic field application on the properties of nickel-based coatings was determined. During metallization, the magnetic field was applied to the sample’s surface with different orientations. Due to the magnetic properties of metallic ions, the influence of the magnetic field on coatings properties is expected. The coatings were analyzed by Energy-dispersive X-ray spectroscopy (ED S) the X-Ray diffraction (XRD ) methods, and surface morphology was observed by scanning electron microscopy (SEM). The catalytic properties in a hydrogen evolution reaction (HER ) were measured by electrochemical method in 1 M NaOH solution. The best catalytic activity has been observed in the case of the ternary Ni-Fe-P alloy deposited under a parallel magnetic field. The primary outcome of the presented research is to produce elements based on 3D printing from resins, which can then be metallized and used for highly-active materials deposited on complex 3D models. Furthermore, these elements can be used as low-cost, highly-developed sensors and catalysts for various chemical processes

Electrochemical Deposition of Ruthenium and Cobalt-Ruthenium Alloys From Acidic Chloride Ions Containing Baths

The article presents results of tests on potentiostatic electrodeposition of ruthenium and Co-Ru alloys. The tests applying the method of cyclic voltammetry with the use of gold disk electrode (RDE) allowed to define a potentials range in which it is possible to obtain ruthenium and its alloys with cobalt from acid chloride electrolytes. The influence of electrodeposition parameters and the electrolyte composition on the composition, morphology and structure of the obtained deposits was determined. Co-Ru alloys underwent XRD tests, an analysis with the XRF method and observations using scanning electron microscopy (SEM)

Electrochemical Deposition of Ruthenium and Cobalt-Ruthenium Alloys From Acidic Chloride Ions Containing Baths

The article presents results of tests on potentiostatic electrodeposition of ruthenium and Co-Ru alloys

Influence of Magnetic Field on Electroless Metallization of 3D Prints by Copper and Nickel

3D printing is a technology with possibilities related to the production of elements of any geometry, directly from a digital project. Elements made of plastic are metalized to give new properties such as conductivity or corrosion resistance. In this work, experimental work related to the electroless deposition of metallic coatings on plastics was carried out. For this purpose, the copper and nickel coatings were catalytically deposited on elements printed using hard-lightened resin. The effect of the metallization time on the properties of copper and nickel coatings was determined. In addition, the process of deposition metals in the magnetic field was analyzed with different direction of magnetic field to the surface of the samples. The coatings were analyzed by XRF, XRD method and morphology of surface was observed by scanning electron microscopy (SEM)

Electrocatalytical Properties of Palladium-Decorated Cobalt Coatings Obtained by Electrodeposition and Galvanic Displacment

This work presents the studies on the electrochemical process of thin palladium layers formation onto electrodeposited cobalt coatings. The suggested methodology consists of the preparation of thick and smooth cobalt substrate via galvanostatic electrodeposition. Cobalt coatings were prepared under different cathodic current density conditions from acidic bath containing cobalt sulphate and addition of boric acid. Obtained cobalt layers were analyzed by x-ray diffraction to determine their phase composition. Freshly prepared cobalt coatings were modificated by the galvanic displacement method in PdCl2 solution, to obtain smooth and compact Pd layer. The comparison of electrocatalytic properties of Co coatings with Co/Pd ones enabled to determine the influence of Palladium presence in cathodic deposits on the hydrogen evolution process

Investigation of Two-Step Metallization Process of Plastic 3D Prints Fabricated by SLA Method

This paper presents the results of experiments on metallization of plastic elements produced using 3D printing technology from the light-hardened resins. The obtained coatings were bimetallic (Cu/Ni). The first step of metallization was the electroless deposition of copper. The second one was electrodeposition of nickel on the previously prepared copper substrate. The parameters of 3D prints preparation and metallization processes were deeply investigated. The etching of plastics substrates and duration of electroless metallization of 3D prints by copper were analyzed. In the next step the influence of nickel electrodeposition time was investigated. The coating were analyzed by XRD method and morphology of surface was analyzed by scanning electron microscopy (SEM). The thickness of coatings was calculated based on mass differences and measured by using optical microscopy method. The optimal parameters for both processes were specified

Study on Synthesis and Modification of Conical Ni Structures by One-Step Method

In this work the conical Ni structures were obtained from an electrolyte containing NH4Cl as a crystal modifier. This process is called one-step method and allows to cover large areas with micro- and nanostructures during a single electrodeposition. Presence of NH4Cl promotes a vertical direction of structure growth in order to block a horizontal one. Additionally, this method does not require using chromic acid solution, which is dangerous for the environment. Due to the ferromagnetic properties of Ni, obtained coatings could be applied as magnetic devices. The influence of the parameters such as a preparation of copper substrate, a composition of electrolyte and electrodeposition conditions (time, the electrolyte temperature and current density) was investigated in this work

Study of Gold, Copper and Nickel Adsorption, from their Acidic Chloride Solutions, Onto Activated Carbon

In this paper, a simple and effective method for gold recovery is described. The paper describes a way to recover gold onto activated carbon from a synthetic solution of gold(III) chloride. The method can also be used on nickel(II) as well as copper(II) chloride of where the metal ion ratios are comparable to the metal ratios found in some electronic waste. With the use of activated carbon in the process of electrolyte purification it is possible to selectively remove gold in metallic form from the solution. XPS studies have confirmed that metallic gold is present on the carbon surface. A spectrophotometric method was used to determine the concentration of Au(III) in the solution. Different concentration of nickel(II) as well as copper(II) were investigated. In all cases, adsorption and reduction of Au(III) to the metallic form was observed