• 에너지공학
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• 제25권4호
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• pp.245-250
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• 2016

이산화망간은 전지의 활성물질로서 우수한 특성을 가지고 있고 가격도 저렴한 재료로서 각종 1차전지에 사용되어왔다. 그러나 이산화망간을 이용한 2차 전지에 대한 연구는 그렇게 많지 않다. 최근 이산화망간의 충전가역성에 관하여 황산아연을 전해질로 하는 이산화망간 아연전지가 재충전이 가능하다는 보고가 있다. 여기서는 이산화망간이 황산아연수용액 중에서 가역적으로 충전방전이 가능한 것을 토대로 2차전지로서의 가능성에 대해 서술한다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.270-274
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• 2001

With Increasing importance of electroless nickel plating technology in many fields such as electronic and automobile industries, the treatment of the spent baths is becoming a serious problem. These spent baths contain iron and zinc as impurities, organic acids as complexing reagents, and phosphonate ions as oxidized species of tile reducing reagent. as well as several grams per liter of nickel. The spent baths are currently treated by conventional precipitation method. but a mettled with no sludge generation is desired. This work aims at establishing a recycling process of nickel from tile spent baths using solvent extraction. Extraction behaviors of nickel. iron. and zinc in various 쇼pes of real spent baths are investigated as a function of pH using LIX841, di (2-ethylhexyl)phosphoric acid (D2EHPA), and PC88A as tile extractants. Nickel is extracted by LIX84I at the equilibrium pH of more than 6 with high efficiency. For the weakly acid baths. iron and zinc are extracted by D2EHPA or PC88A without adjusting the pH of the baths leaving nickel in the aqueous phase. Stripping of nickel from LIX84I with sulfuric acid is also investigated. It is shown that concentrated nickel sulfate solution (> 100 ㎏-Ni/㎥) is obtained. This solution can be reused in the electroless plating process. Based on these findings, flow sheets for recovering nickel from the spent baths are proposed.

• 한국수소및신에너지학회논문집
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• 제23권4호
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• pp.390-396
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• 2012

In order to understand the nature of dendritic zinc growth, electrochemical zinc redox reaction on nickel plate was investigated in aqueous solutions containing different concentrations, 0.2, 0.1 and 0.02 $mol{\cdot}dm^{-3}$ (M), of zinc sulfate ($ZnSO_4$) or zinc chloride ($ZnCl_2$). Zinc ion was efficiently reduced and oxidized on nickel in the high-concentration (0.2 M) solution, whereas relatively poor efficiency was obtained from the other low-concentration solutions (0,1 and 0.02 M). Cyclic voltammetry (CV) analysis revealed that the 0.2 M electrolyte solution decomposes at more positive potentials than the 0.1 and the 0.02 M solutions. These results suggested that the concentration of electrolyte solution and anion would be an important factor that suppresses the reaction of the zinc dendrite formation. Scanning Electron Microscopy (SEM) data revealed that the shape of dendritic zinc and its growing behavior were also influenced by electrolyte concentration.

• 한국염색가공학회지
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• 제24권4호
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• pp.247-252
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• 2012

The objective of this study was to find an appropriate method and process for protecting the green color in bamboo leaves and subsequent extraction of the green colorants, chlorophyll. Various inorganic salts including cupric sulfate, ferric sulfate, and zinc chloride were employed as green color protectors. Accordingly, the effects of metal salts and treatment conditions on color protection were investigated to find appropriate protector and conditions. And also, the efficacy of bamboo colorants as a natural green dye was evaluated through dyeing and colorfastness tests. Antimicrobial activity of dyed fabrics was measured by shake flask method in terms of bacterial reduction rate using Staphylococcus aureus(ATCC 6538). On the basis of experimental results for stabilizing bamboo leaves colorants, it was confirmed that Cu was the most appropriate metal type considering dye uptake, photostability and light fastness, and its optimum concentration was 0.025%. After the stabilization, the colorants were extracted efficiently at NaOH aqueous solution of 1.00%. It was concluded that bamboo leave has a high potentiality as new resources to produce a natural green dye with antimicrobial functionality.

• 자원리싸이클링
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• 제32권1호
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• pp.33-41
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• 2023

본 연구에서는 제강분진으로부터 습식제련을 이용하여 아연을 선택적으로 회수하고 황산아연을 제조하고자 하였다. 제강분진의 성상분석을 통해 기존의 제강분진과 다르게 철의 함유량이 9.9%로 상대적으로 낮고 망간이 19%로 다량 함유되어 있었으며 이에 알맞은 습식제련 공정을 설계하였다. 침출공정에서는 고액비, 온도, 황산 농도별 실험을 통해 1.6M 황산, 20% 고액비, 60℃, 1시간동안 침출하여 85%의 아연, 망간을 용해시키고 철은 침출되지 않았다. 망간으로부터 아연을 선택적으로 회수하기 위해 D2EPHA를 사용한 용매추출 공정을 선택하였고 0.8M D2EHPA, 32% 비누화도, O/A 비 2, 향류 3단 추출을 통해 에서 99% 아연을 추출하였으며, 공동 추출된 망간은 pH 1.5로 조정한 황산 수용액으로 전량 세정하였다. 최종적으로 1.5M 황산을 이용하여 O/A 비 4, 향류 4단 탈거를 통해 아연을 농축 탈거하였다. 탈거액에는 40g/L의 아연이 함유되어 있었으며 이를 감압증류하여 99.9%의 황산아연 1수화물을 획득하였다.

• Bulletin of the Korean Chemical Society
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• 제22권8호
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• pp.821-826
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• 2001

Solvent sublation has been studied for the separation and determination of trace Zn(Ⅱ) and Pb(Ⅱ) in water samples. A synergy producing method was utilized to improve the efficiency of extraction in the sublation using an ion-pair of metal-naphth oate {M-(Nph)3- } complexes and tetra-n-butylammonium (TBA+ ) ion. After the M-(Nph)3- complexes were formed by adding 1-naphthoic acid to the sample solution, tetra-n-butylammonium bromide was added in the solution to form the ion-pair. And sodium lauryl sulfate (SLS) was added to make the ion-pair hydrophobic. The ion-pairs of the metal complexes were floated and extracted into methylisobutyl ketone (MIBK) from the aqueous solution by bubbling with nitrogen gas in a flotation cell. Metal ions in MIBK solution were measured by graphite furnace-AAS. Experimental conditions were optimized as follow so. After the pH of a 1.0 L water sample was adjusted to 5.0, 6.0 mL of 0.1 M 1-HNph and 10 mL of 0.03 M TBA-bromide were added to the sample to form ion-pairs, and 2.0 mL of 0.2%(w/v) SLS was added to make the ion-pairs hydrophobic. The solution was bubbled with 30 mL/min N2 gas for 5 minutes in a flotation cell. Linear calibration curves were obtained for the determination of Zn(Ⅱ) and Pb(Ⅱ) in several water samples. Reproducible results of showing a relative standard deviation of < 10% and recoveries of 80-100% could be obtained.