Production Of Copper Powder Research Articles

Achieving Optimal Dendritic Morphology in Ultralight Copper Powder Production through Hydrochloric Acid Intervention

Achieving Optimal Dendritic Morphology in Ultralight Copper Powder Production through Hydrochloric Acid Intervention

Production of Copper Powders by Alternating Current Polarization of a Copper–Titanium Electrode Pair

Production of Copper Powders by Alternating Current Polarization of a Copper–Titanium Electrode Pair

Machine learning‐based analysis and prediction of the interfacial corrosion processes of copper cathode plates during the electrolytic production of copper powders

AbstractPresent efforts to support the essential industrial‐scale electrolytic production of copper‐based metal powders urgently require approaches to the real‐time predicting of corrosion of copper cathodes employed in electrolytic production processes. However, current approaches are extremely limited owing to the difficulty of accurately modeling the complex cathode corrosion process. In this study, the corrosion process under different parameters was analyzed by a self‐designed continuous electrolytic corrosion experimental device, clarify the influence mechanism of current density on the corrosion of the solid–liquid–gas interface area, and addresses this issue by applying a random forest machine learning approach based on three process parameters, including the electrolyte temperature, liquid‐level fluctuation cycle period, and current density. The dataset employed in the model is obtained using a novel experimental corrosion test method based on electrode arrays. The experimental results include the corrosion rates of copper cathode plates at different positions relative to the liquid electrolyte level during the electrolysis process. The resulting stochastic model is demonstrated to obtain a high prediction accuracy of 97% for the various regions of copper cathode plates defined according to liquid electrolyte level.

Ecologically friendly production of copper powder and elimination of cupric ions from aqueous solutions using D-Glucose and ascorbic acid

Copper(II) ions (Cu2+) in copper sulfate solutions (CuSO4) can be reduced with several carbohydrates to produce copper metal powder. In this study glucose was used as a reducing agent. The big challenge in this study was to find the optimum conditions for copper ions reduction because they were entwined with positive conditions for degradation and hydrolyses of sugar (D-glucose). For that reason, the impact of several parameters on these conditions was investigated in a series of experiments in this research study. The glucose concentration (0.2-1.6M), the temperature (30-70 °C), initial sodium hydroxide concentration (0.2-0.4M), the role of adding sulfuric acid (H2SO4) at different volumes (0.6-3 mL) and the addition of ascorbic acid at different doses (4-20 mL) were the considered key parameters that were studied in this research. The synthesis of copper was restricted due to organic acid build up and reactions of the degradation products and copper. Under optimum conditions using glucose as a reducing agent, maximum of 48% of copper ions were transformed to copper metal (Cu). By adding ascorbic acid at the end of the experiment process, reduction efficiency was 100% where total and complete copper reduction was achievable. Most of solid particles were analyzed and the characterization and nature of the produced solid was achieved by X-Ray Diffraction.

Production of Copper Powder by Electrodeposition with Different Equilibrium Crystal Shape

The copper powder is electrodeposited from copper sulfate pentahydrate (CuSO4·5H2O) and sulphuric acid (H2SO4) bath. The polarization study is carried out to get an indication of limiting current density or deposition potential. Solutions are prepared with different concentrations of CuSO4·5H2O, i.e., from 0.015 to 0.35 M. Additives like sodium dodecyl sulfate (SDS) and cetyltrimethylammonium bromide (CTAB) are used during electrodeposition. To elucidate the effect of additive on the copper electrodeposition, an equal concentration of SDS and CTAB is used for a particular concentration of CuSO4·5H2O. The examination of surface topography is carried out with the help of a scanning electron microscope. In the absence of additive, the morphology is a honeycomb like structure. However, the deposits are dendritic in nature in the presence of the additive. The smallest constituent in the dendrites is different for both the additive added solutions. In the case of CTAB, the smallest constituent is a flower like structure where microspheres of copper are embedded with nanosheets. On the other hand, the faceted crystal appears for SDS added solution. SHAPE V 7.4 software is used to draw the equilibrium crystal shape. In summary, it is concluded that the dissimilarity in the smallest constituent of dendritic morphology is associated with the concentration of the surfactant.

Comparative morphological and crystallographic analysis of copper powders obtained under different electrolysis conditions

Abstract Production of copper powders by the potentiostatic electrolysis under different hydrogen evolution conditions was investigated. Copper powders were characterized by the scanning electron microscope (SEM), X-ray diffraction (XRD), particle size distribution (PSD), and by the determination of the specific surface area (SSA) of the formed powders. Depending on quantity of hydrogen generated during electrolysis, the two types of particles were formed: dendrites and cauliflower-like particles. The dendrites were formed without, while cauliflower-like particles with the quantity of evolved hydrogen enough to achieve strong effect on hydrodynamic conditions in the near-electrode layer. Although macro structure of the particles was very different, they showed similar micro structure. Namely, both types of the particles consisted of small agglomerates of approximately spherical Cu grains at the micro level. The existence of the spherical morphology was just responsible for random orientation of Cu crystallites in both types of particles. The SSA of cauliflower-like particles was more than two times larger than that of the dendrites, while their size was considerably smaller than that of the dendritic particles. In this way, the useful benefit of Cu powder formation in the conditions of vigorous hydrogen evolution is shown.

Production of Copper Powder from Ores by Elecrodeposition Process

This paper studies the preparation of Copper powder from copper sulphate aqueous solution (CuSO4.5H2O), sulfuric acid (H2SO4) and copper chloride (CuCl2.2H2O) by using the process of electrodeposition. Process of Powder deposition has been investigated for copper powder; it is a fine layer on cathode electrode by using the value of different from time of deposition (15, 30, 45, and 60) min. it is noticed the weight of the powder rises with the rise of time of depostion.
 Diffractions of X-ray (XRD) revealed high crystallinity and pure copper powder not contain impurity or oxides. Optical microscopes have revealed the particles of copper have dendritic shapes. The size of Particles analyzer measured the size of a particle which is about (4.645) μm.

Effect of jet flow between electrodes on power consumption and the apparent density of electrolytic copper powders

Electrolysis is one of the main methods for producing copper powder, but has the disadvantage of high power consumption. This paper describes an experimental study of a process for electrolytic production of copper powder in which a jet flow of fresh electrolyte is introduced between anode–cathode pairs. The effects of electrolyte inlet mode and circulation rate on the direct current (DC) power consumption and on the morphology and apparent density of the copper powder produced are investigated. The results show that in the conventional bottom-inlet/top-outlet mode, the electrolyte circulation rate has little influence on DC power consumption. In contrast, when a jet flow is used, an increase in electrolyte circulation rate leads to an increase in current efficiency and a decrease in cell voltage, resulting in a significant reduction in DC power consumption, which drops by as much as 37%. In addition, as a result of agitation by the jet flow, the copper powder deposited at the cathode becomes denser, the powder particles become coarser and less dendritic on the microscale, and their apparent density increases from 0.33 g cm−3 to 1.90 g cm−3.

Effect of Flow Pattern on Energy Consumption and Properties of Copper Powder in the Electrolytic Process

Because of distinctive properties, such as dendritic structure, high green strength, and low oxygen content, electrolytic copper powder has been widely used in aviation, aerospace, national defense industry and other domains. But at present, energy consumption of the electrolysis process in copper powder production is high, and the current efficiency is only about 90%. Therefore,the decrease in energy consumption of the electrolysis process has become the major bottlenecks in the development of the enterprises. In this paper, a new electrolysis cell with different electrolyte inlet arranged on the cell was manufactured. Then, the effect of flow pattern of electrolyte on the current efficiency, energy consumption and properties of copper powder was investigated. The experimental results showed that the electrolytic process had the higher current efficiency, lower energy consumption and smaller copper powders when the flow rate is 0.5l/min in the paralleled inlet and 1.5 l/min in the traditional inlet. Under the optimal conditions, the current efficiency, energy consumption and copper powder size were 99.10%, 712.90kw∙h/t and 47.80um respectively. This means an obvious rise in current efficiency and decrease in energy consumption compared to traditional feeding method.

An Investigation on Copper Powder Production from Aqueous Solution by Reductive Precipitation with Sugar Beet Molasses in an Autoclave

An Investigation on Copper Powder Production from Aqueous Solution by Reductive Precipitation with Sugar Beet Molasses in an Autoclave

Direct electrolytic refining of end-of-life industrial copper waste scraps for production of high purity copper powder

The end-of-life electric cables from both domestic and industrial sources offer an attractive resource of copper metal. In addition, copper wastes generated during fabrication of copper components remains another valuable source of recyclable copper. This work reports a simple, cost-effective and eco-friendly direct electrolytic refining using waste electrical copper wire scrap and copper plate rejects for producing the value added high purity copper powder. Suitable anode support system was applied in which compressed wire scrap or copper plate rejects were held to make anode for electrolytic cell. Electrolysis parameters like current density, acid concentration and copper ion concentration were varied to arrive at optimum condition. Results showed the energy consumption of 1.44 kW h/kg at 89% current efficiency for producing the copper powder, that consisted of >80% of–325 mesh size particles, from waste copper wire anodes. However, slightly lower energy consumption of 1.32 kW h/kg at 91% current efficiency was observed during production of copper powder from copper fabrication rejects. The copper powder thus produced was characterised by chemical analysis, XRD and optical microscope to examine the purity and morphology etc. and found suitable for powder metallurgical applications. Present investigations have established the potential utilisation of copper waste wire scrap and copper plate rejects for the production of value added high purity copper powder.

Effect of the Molten Metal Stream’s Shape on Particle Size Distribution of Water Atomized Metal Powder

The current knowledge indicated that water pressure, molten metal temperature, water flow rate and water jet configuration are very important factors which affect on the particle size distribution and shapes of atomized powder. This study aimed to investigate whether the shape of molten affects the particle size of atomized powder. The experiments were the production of copper powder with the fixed atomization process conditions, but varied the shape of molten metal by using two different shapes of tundish nozzle’s orifice to make the round and rectangular cross section of molten metal stream. There were three sizes for each orifice shape to determine the rate of production (metal flow rate) at 13 kg/min, 19 kg/min and 26 kg/min. The results showed that at the same flow rate of molten metal the production of flat metal stream from rectangular orifice made higher yield of finer particle, smaller median size (D50) and narrower range of size distribution than the production with the round cross section orifice for every production rates.

Production of copper powder from synthetic wastewaters by cementation on a longitudinal finned rotating zinc cylinder

This study aims to the enhancement of Cu2+ ions removal from wastewaters and recovery of the metal value by cementation on a longitudinal finned rotating zinc cylinder. The effect of different parameters such as cylinder rotational speed (rpm), initial Cu2+ ions concentration and the effect of the fin height to cylinder diameter (e/d) on the rate of Cu2+ ions cementation was investigated. In addition, the effect of drag reducing polymer on the rate of Cu2+ cementation was examined. The rate of cementation was expressed in terms of the mass transfer coefficient. The results revealed that the mass transfer coefficient increases with increasing rpm, initial Cu2+ concentration and e/d ratio. The present results show that finned rotating cylinder enhances rate of cementation compared to smooth rotating cylinder by percentage ranges from 28.79 to 134.85 depending on the operating conditions. On the other hand, the presence of drag reducing polymer retards the rate of cementation. The present data fit the following dimensionless equations: For smooth cylinder: Sh = 0.74 Re0.69 Sc0.33. For finned rotating cylinder: Sh = 0.38 Re0.9 Sc0.33 (e/d)0.25. The importance of the above correlations in the design and operation of industrial-scale rotating cylinders cementation reactors was pointed out.

The effect of process parameters on copper powder particle size and shape produced by electrolysis method

In this study, an electrolyzing device for the production of metal powders was designed and fabricated. The production of copper powders was performed using a variety of current densities, anode-cathode distances and power removal times. The effect of these parameters on powder particle size and shape was determined. Particle size was measured using a laser diffraction unit while the powder shape was determined by SEM. Experimental results show that an increase in current density leads to a decrease in powder particle size. In addition particle shape changed from globular dendritic to acicular dendritic with increasing the current density. Distance between the cathode and anode also showed a similar influence on powder particle size and shape. An increase in time of powder removal led to an increase in powder particle size, as the shape changed from acicular dendritic to globular dendritic.

Production of copper powder form printed circuit boards by electrodeposition

During the last years, the waste electrical and electronic equipment (WEEE) are gathering attention, as a very special section of waste. In fact, they have been proven to be source for the recovery of metals. In the present study printed circuit boards (PCBs) were cut and treated thermally at 500oC for 1 h in both air and nitrogen atmosphere. The obtained material was dissolved in three different acid media HNO3aq, HClaq and H2SO4aq, in order to extract copper. The achieved Cu recovery percentages were 97.5, 65 and 76.5% respectively. Electrodeposition technique was applied in order to recover copper in powder form. More than 98% of copper was recovered achieved by application of high current density resulting to dendritic structure of copper. The applied process was characterised by a high current efficiency and led to the production of copper powder of 80 μm mean diameter appropriate for powder metallurgy applications.

Velocities of copper droplets in the De Laval atomization process

Atomization experiments were carried out at the Nanoval atomization unit. Particle image velocimetry (PIV) was used to determine the velocity vector fields of copper powder production via De Laval gas atomization. The experimental set-up designed to access the area closest to the atomization point was described in detail. Velocity vector fields were constructed by taking into account the distance from the nozzle exit. Instantaneous velocities on the atomization axis were calculated as a function of the atomization duration. Results from this study indicate a strong influence of the atomization pressures and the melt nozzle diameters on velocity characteristics. After processing, the droplet sizes were analyzed in relation to the working conditions using a Spraytec analyzer. A close relationship between velocity values and droplet sizes, depending on the operating parameters, was demonstrated.

Comparison of effective parameters for copper powder production via electrorefining and electrowinning cells and improvement using DOE methods

The influences of cupric ion concentration (5–35 g/L), current density (500–2000 A/m2), circulation rate of the electrolyte solution (15–120 mL/min), and temperature (25–60°C) on the physical and chemical properties of copper powders obtained in electrolysis cells were investigated. Two industrial processes, electrorefining (ER) cells with a synthetic electrolyte and electrowinning (EW) cells with an original solution of copper mineral leaching, were utilized to produce copper powders. Finally, the statistical full factorial method of design of experiments (DOE) was employed to investigate the interaction or the main effects of processes. The results show that increasing the copper concentration and temperature can increase the grain size, apparent density, and electrical energy consumption. On the other hand, increasing the current density and circulation rate of the electrolyte can decrease them. This production process is optimized via DOE to control the interactive and main effects to produce copper powders with favorable properties.

Production of copper powder from wastewater containing CuSO 4 and alcoholic additives in a modified stirred tank reactor by cementation

The kinetics of cementation of copper from copper sulphate solutions in a stirred tank reactor fitted with a rotating perforated basket of novel geometry packed with zinc Raschig rings were studied. The effect of different parameters such as initial copper sulphate concentration, basket rotational speed, temperature and the effect of presence of some alcohols, such as methanol, ethanol and butanol were studied. The rate of cementation was found to increase with increasing initial copper sulphate concentration, basket rotational speed, and temperature, while a decrease in the rate of copper cementation was observed in the presence of alcohols according to the following order: butanol > ethanol > methanol. The thermodynamic activation parameters ∆H ≠, ∆G ≠ and ∆S ≠ were calculated within the range of temperature studied. The activation energy was found to be 6 J/mol K which confirms the diffusion controlled nature of the reaction. Mass transfer study of the process has revealed that the present data can be correlated by the equation: Sh = 0.00 13 Sc 0.33 Re 0.943 for the conditions: 2056 < Sc < 2202 and 6700 < Re < 28,300. A comparison between the present modified stirred tank reactor with the rotating cylinder reactor and the rotating disc reactor has shown that a higher rate of cementation was obtained in the present reactor.

Production of copper powder from rolled scale and its mechanical properties

A laboratory installation for producing copper powder from rolled scale metal has been developed. Processing modes are determined for reducing annealing to produce copper powder with optimal mechanical properties which are close to those of PMS-1 electrolytic copper. The installation developed at the Gas Institute of the National Academy of Sciences of Ukraine and the process of producing copper powder from scale material can be recommended for commercial use.

Confinement and aspiration of dust and gas in the production of atomized copper powders

A system for the confinement and aspiration of dust and gas emissions is developed. A movable casing installed on an induction crucible furnace prevents air contamination when melt is prepared and atomized to produce copper powders and alloys. The content of harmful admixtures in air at workplaces does not exceed the threshold limit value. The research has provided input data to develop aspiration and dust separation systems for the production of copper powders and alloys.