• Clean Technology
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• v.2 no.1
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• pp.47-52
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• 1996

The solvent extraction method was applied on a spent solution containing copper, which was produced in a printed circuit board process, to recover copper and to reuse the etching solution. Lix 64 N ($\alpha$-Hydroxyoxime + $\beta$-Hydroxybenzophenone Oxime) was used as a solvent. The acidic spent copper solution was mixed with and alkaline copper solution to pH=2. The solvent including 30 volume% of Lix 64 N extracted 17.1gr/l of copper from the mixed spent copper solution. In the continuous bench scale experiment, 4 stages for extraction, 2 stages for stripping and 4 stages for washing were used. Recovered copper was recycled as copper sulfate and the raffinate was reused as copper etchant. The percentage of copper recovery and the purity of copper sulfate were higher than 99.9%, respectively.

• Journal of Adhesion and Interface
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• v.4 no.3
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• pp.1-8
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• 2003

Adhesion between rubber compound and copper-film-coated steel plate (abbreviated hereafter as copper film plate) with different thicknesses of copper film was investigated. Two different methods were employed for the preparation of the copper film plates: a substitution plating of preelectroplated zinc with copper ion and a vacuum sputtering of copper on steel plate. Adhesion strength of the copper film plates with rubber compounds was largely dependent upon the thickness of copper film, regardless of their preparation methods. The copper film plates with thinner thickness than 75 nm showed high adhesion comparable to brass, while those with thicker copper film showed poor adhesion due to excessive growth of copper sulfide at adhesion interface.

• Journal of the Microelectronics and Packaging Society
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• v.27 no.3
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• pp.55-60
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• 2020

The recent semiconductor packaging technology is evolving into a high-performance system-in-packaging (SIP) structure, and copper-to-copper bonding process becomes an important core technology to realize SIP. Copper-to-copper bonding process faces challenges such as copper oxidation and high temperature and high pressure process conditions. In this study, the bonding interface quality of low-temperature copper-to-copper bonding using a two-step plasma treatment was investigated through quantitative bonding strength measurements. Our two-step plasma treatment formed copper nitride layer on copper surface which enables low-temperature copper bonding. The bonding strength was evaluated by the four-point bending test method and the shear test method, and the average bonding shear strength was 30.40 MPa, showing that the copper-to-copper bonding process using a two-step plasma process had excellent bonding strength.

• Korean Journal of Microbiology
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• v.12 no.1
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• pp.25-30
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• 1974

It was convinced that with a relatively small capital investment and with a low operating cost, appreciable amounts of cement copper could be produced from low-grade minerals by the application of a bacterial leaching method. For the recovery of cement copper from the impure pregnant solution, direct precipitation of copper with tin plates by a bacterial leaching method was feasible. The results obtained were as follows: 1)In order to remove the cement copper from the reducing metal, aeration and agitation method were more effective and economic than shaking method. 2)The rate of copper recovery from the pregnant solution was accerelated according to increasing quantities of reducing metal. However, the excess of reducing metal reduced the grade of cement copper. 3)Among the comparative experiments of copper recovery at each reaction temperature of $10^{\circ}C$, $20^{\circ}C$, and $30^{\circ}C$, the recovery rate of copper at $30^{\circ}C$from the pregnant solution was highest. 4)Direct cementation method on iron-containing metal was an excellent method for the recovery of cement copper in bacterial leaching.

• Journal of Electrochemical Science and Technology
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• v.8 no.2
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• pp.146-154
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• 2017

In this study, copper (II) oxide was prepared for use in a copper electroplating solution. Copper chloride powder and copper (II) oxide are widely used as raw materials for electroplating. Copper (II) oxide was synthesized in this study using a two-step chemical reaction. Herein, we developed a method for the preparation of copper (II) oxide without the use of sintering. In the first step, copper carbonate was prepared without sintering, and then copper (II) oxide was synthesized without sintering using sodium hydroxide. The optimum amount of sodium hydroxide used for this process was 120 g and the optimum reaction temperature was $120^{\circ}C$ regardless of the starting material.

• YAKHAK HOEJI
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• v.26 no.2
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• pp.97-103
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• 1982

This paper presents anti-inflammatory effects of nonsteroidal anti-inflammatory drugs and their copper complexes, and the change of content of copper in serum, liver, brain and edema foot induced by 1% carrageenan in rats, and also investigation of stomach hemorrhage. The results were as follows. 1. The content of copper decreased in liver and brain, however, the concentration of copper significantly increased in serum and edema site after carrageenan injection in rats. 2. The content of copper in serum and edema site was decreased after administration of anti-inflammatory drugs. 3. Edema inhibition rate of aspirin was, higher than that of copper (II) aspirinate, but edema inhibition rate of copper complex of naproxen was markedly higher than that of naproxen. 4. Hemorrhage of stomach of copper salicylate was higher than that of sodium salicylate, but hemorrhage of stomach of sodium naproxen was higher than that of copper naproxen.

• Bulletin of the Korean Chemical Society
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• v.22 no.4
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• pp.379-382
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• 2001

A new ligand containing the long aliphatic hydrocarbon chain, dipyridylstearylamine (dps) and its copper(Ⅱ) complex, Cu(dps)(NO3)2 have been prepared. The copper complex was characterized structurally and spectroscopically. The XRD crystal structure of the copper complex reveals that copper is octahedrally coordinated by dps and two nitrato ligands. The nitrato groups ligate asymmetrically to the copper. Crystal data are P1bar, a=8.249(2), b=10.416(3), $c=20.915(4)\AA$, $\alpha=86.54(2)$, $\beta=84.026(2)$, $\gamma=72.32(2)^{\circ}$, V=1702.7(7) $\AA3$ , Z=2, ${\lambda}$(Mo $K\alpha)=0.71073\AA$, $\mu=0.689$ mm-1 , T=293(2) K, R=0.0560 for 3529 reflections. The dps and the copper complex are stable in the air and the copper complex exhibits features of typical of other copper(Ⅱ) complexes containing dipyridylamine-based ligand.

• Journal of Environmental Science International
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• v.1 no.2
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• pp.157-166
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• 1992

The biosorptlon perFormances of copper were Investigated by the immobilized biomass of nonliving marine brown algae Undaria pinnatifida by each of the Ca-alginate method(Ca-ALG), Ba-alginate method(Ba-ALG), polyethylene glycol method(PEG), and carrageenan method (CARR). The copper removal performance increased but the copper uptake decreased as the biomass amount was increased. However, the copper uptake by the immobilized biomass increased with increasing initial copper concentration. Among the immobilization methods, the copper uptake decreased in the following sequence: Ca-ALG > Ba-ALG > PEG > CARR. The pattern of copper uptake by the immobilized biomass fitted the Langmuir isotherm better than the Freundlich isotherm. Desorption of deposited copper with 0.05 ~0.5M HCI, resulted in no changes of the copper uptake capacity of the immobilized biomass by the immobilization methods except for PEG, through five subsequent biosorptioydesorption cycles. There was no damage to the immobilized biomass which retained its macroscopic appearance in repeated copper uptake/elution cycles.

• Journal of Environmental Science International
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• v.19 no.9
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• pp.1119-1127
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• 2010

The behavior of copper throughout the whole process of wastewater treatment plant that uses the activated sludge process to treat the wastewater of petrochemical industry that contains low concentration of copper was investigated. Total inflow rate of wastewater that flows into the aeration tank was $697\;m^3$/day with 0.369 mg/L of copper concentration, that is, total copper influx was 257.2 g/day. The ranges of copper concentrations of the influent to the aeration tank and effluent from the one were 0.315 ~ 0.398 mg/L and 0.159 ~ 0.192 mg/L, respectively. The average removal rate of copper in the aeration tank was 50.8 %. The bioconcentration factor (BCF) of copper by microbes in the aeration tank was 3,320. The accumulated removal rate of copper throughout the activated sludge process was 71.3%, showing a high removal ratio by physical and chemical reactions in addition to biosorption by microbes. The concentration of copper in the solid dehydrated by filter press ranged from 74.8 mg/kg to 77.2 mg/kg and the concentration of copper by elution test of waste was 2.690 ~ 2.920 mg/L. It was judged that the copper concentration in dehydrated solid by bioconcentration could be managed with the control of that in the influent.

• Journal of the Korean institute of surface engineering
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• v.49 no.5
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• pp.401-407
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• 2016

In this work, effect of zincate treatment of AZ91 Mg alloy on the following electrodeposition of copper was examined in a non-cyanide bath containing pyrophosphate ions in view of surface morphology and adhesion of the electrodeposited copper layer. Without zincate treatment, the electrodeposited copper layer showed very porous structure and poor adhesion. On the other hand, the copper layer electrodeposited on the zincate-treated surface showed dense structure and good adhesion. The dissolution rate of AZ91 Mg alloy after the zincate treatment appeared to decrease about 40 times in the copper pyrophosphate bath, as compared to that of the surface without zincate treatment. The porous morphology and poor adhesion of a copper layer on the AZ91 Mg alloy surface without zincate treatment were attributed to small number of nucleation sites of copper because of rapid dissolution of the magnesium substrate in the pyrophosphate bath. Based on the experimental results, it is concluded that the zincate treatment to form a conducting and protecting layer on the AZ91 Mg alloy surface is essential for successful electrodeposition of a copper layer on AZ91 Mg alloy with good adhesion and dense structure in the copper pyrophosphate bath.