• Resources Recycling
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• v.10 no.4
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• pp.18-23
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• 2001

Air pollutants, phenol was generated in case of thermal regeneration of used activated carbon loaded with phenol and because of this problem, removal process of phenol were studied. Electrolytic oxidation of samples, used S.company granular activated carbon (WS-GAC), used C.company granular activated carbon (WC-GAC) and used L.company granular activated carbon (WL-GAC) loaded with phenol carried out by potentiostatic method in this study. In case of experiment was to come into operation in condition of samples containing 100 mg/g phenol, supporting electrolyte was 1.0% sodium chloride solution, Ti-Ir (10$\times$10$\textrm{cm}^2$) electrode and electrode distance was 2 cm, current density was $1.25 A/dm^2$, Obtained from the results of electrolytic oxidation experiments were not detected residual phenol. And then we knew about reaction time of electrolytic oxidation, current density, concentration of supporting electrolyte and electrode and electrode distance were 60 minutes, 1.25 A/dm$^2$, 1.0%, 2 cm.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2004.06a
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• pp.245-245
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• 2004

현재 한국원자력 연구소에서 개발되고 있는 사용후 핵연료의 차세대관리기술은 산화물 핵연료를 전해환원시켜 금속으로 관리하는 기술이다. 이 공정에서 발생된 LiCl 폐용융염은 Cs, Sr과 같은 핵분열 생성물을 함유하고 있으며, 그 자체로서 수용성이고 방사선에 분해가 잘 되므로 처분 수용기준에 맞게 안정화시켜 처리해야 한다. 현재 이를 처리하기 위한 방법으로 고온에서도 핵분열 생성물의 이온교환 및 흡착이 가능한 제올라이트 A를 이용한 이온교환 및 단순혼합 방식이 주로 적용되고 있다.(중략)

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2017.05a
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• pp.144-144
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• 2017

제한된 조건에서 타이타늄을 양극산화 하였을 때, 자기 정렬된 나노 튜브 형태의 티타니아 구조를 얻을 수 있으며, 그 형태는 양극산화 조건에 따라 변할 수 있음은 학계에 이미 잘 알려져 있다. 그러나 자세한 메커니즘과 전기화학적 조건들은 아직 명확하게 밝혀지지 않았다. 본 연구에서는 자기 정렬된 티타니아 나노 구조의 형태학적 변화를 인가전압과 혼합 전해질의 농도를 변화시켜가며 체계적으로 연구하여, 티타니아 나노 튜브와 마이크로 콘이 생성되는 조건에 대한 지도를 그렸다. 일반적으로 인가 전압이 증가하고, 혼합 전해질에서의 불산의 농도가 낮을수록, 티타니아 나노 구조가 나노튜브에서 마이크로 콘으로 변화하는 것을 확인하였다. 티타니아의 다양한 기능적인 특성을 바탕으로, 구조변화에 대한 전기화학적 이해를 통해, 물 분해, 연료 감응형 태양전지(DSSCs), 광촉매, 가스 센서 등에 적용될 수 있을 것으로 기대한다.

• 한국신재생에너지학회:학술대회논문집
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• 2011.11a
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• pp.85.2-85.2
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• 2011

현재 중온의 고체산화물 연료전지를 위해 다양한 전해질에 대한 연구되었으며 1994년 Ishihara et al.에서 1074K의 온도에서 높은 이온전도도를 갖는 페록스카이 구조를 갖는 LSGM 물질을 발표하였다. Sr과 Mg을 도핑한 Lanthanum gallate는 이온전도도가 1073K에서 0.14S/cm로 YSZ의 5배로 높은 이온전도도를 갖고 있으며 산화환경에서부터 환원환경에서 화학적으로 안정한 특성을 갖고 있다. 또한 LSGM 전해질은 넓은 산소 농도범위에서 안정적인 특성을 갖는 장점을 갖고 있다. 그러나 LSGM은 가장 널리 사용되는 연료극의 Ni 촉매와 고온 소결시 상호확산현상에 의한 2차상을 생성시켜 성능 저감의 원인으로 그 해결방안이 요원한 실정이다. 이에 본 논문에서는 LSGM 전해질에 LSGM scaffold를 형성하고 형성된 scaffold에 연료극 촉매 solution을 infiltration 시켜 저온에서 anode를 형성하여 그 성능을 연구하였다.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2014.11a
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• pp.227-228
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• 2014

마그네슘은 금속 재료중 화학적 활성이 높아 내식성 향상을 위해 표면처리 공정이 반드시 필요하다. 플라즈마 전해 산화를 통한 산화 피막 생성 후 좀더 높은 내식성 향상을 위해 전착 도장법을 사용할 수 있다. 본 논문에서는 전원 인가 방식에 따라 pulse 전원을 on/off 비율에 따른 피막 두께 변화를 측정 하였고 전착 도장을 시행 하여 cross cut test를 통한 부착성 시험을 진행해 on/off 비율 1:4 조건에 250V 전압을 인가 하였을 때 부착성이 가장 우수함을 확인 하였다. 또한 플라즈마 전해 산화 후 탕세 공정을 통해 전착 도장의 내열탕 시험 후 표면 blister의 개선 효과를 얻을 수 있었다.

• Resources Recycling
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• v.17 no.6
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• pp.24-33
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• 2008

The leaching of Cu from waste PCBs was investigated with electro-generated chlorine as an oxidant. The leaching experiments were carried out according to the design of experiments to analyze quantitatively the effect of parameters on copper leaching. From the analysis of variance (ANOVA) it was suggested that the effective parameters were current density, temperature, concentration of HCl, and the interaction between the concentration of HCl and temperature. Especially, the effect of current density was analyzed to contribute to the interpretation of result for copper leaching up to 95.7%. A multiple regression model obtained from the analysis of effective parameters explained 99% of leaching results. From the model equation, it was found that the effect of HCl concentration on copper leaching increased with temperature.

• Journal of the Korean Institute of Gas
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• v.20 no.5
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• pp.34-39
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• 2016

This study is experimentally investigated brown gas generative properties with the changes of cell areas, a electrolyte concentration and ampere current for the developments of small brown gas generation equipments usable in diesel cars. Electrolysis reactors have been manufactured as SMT30, SMT50, SMT50-1, SMT70, SMT90, respectively on various surface areas and different positions anode and cathode. Thus, the brown gas generative properties on reactors tended to increase as surface area increase, and show differences in different electrode positions. However, the effect on electrolyte concentration had increased with a decreasing electrolyte concentration of NAOH 3~1‰, and the brown gas generative properties on ampere of SMT30, SMT50, SMT50-1, SMT70, SMT90 have shown to be $0.74{\ell}/10min$, $1.0{\ell}/10min$, $1.10,{\ell}/10min$, $0.97{\ell}/10min$, $1.13{\ell}/10min$.

• Korean Chemical Engineering Research
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• v.53 no.2
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• pp.145-149
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• 2015

The electrochemical behavior of $Nd_2O_3-La_2O_3-NiO$ mixed oxide including rare earth resources has been studied to synthesize $La_{0.5}Nd_{0.5}Ni_5$ alloy in a LiCl molten salt. The $Nd_2O_3-La_2O_3-NiO$ mixed oxide was converted to $NiNd_2O_4$ (spinel) and $LaNiO_3$ (perovskite) structures at a sintering temperature of $1100^{\circ}C$. The spinel and perovskite structures led a speed-up in the electrolytic reduction of the mixed oxide. Various reaction intermediates such as Ni, $NiLa_2O_4$ were observed during the electrochemical reduction by XRD analysis. A possible reaction route to $La_{0.5}Nd_{0.5}Ni_5$ in the LiCl molten salt was proposed based on the analysis result.

• Applied Chemistry for Engineering
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• v.16 no.5
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• pp.635-640
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• 2005

Mediated electrochemical oxidation (MEO) is an aqueous process which oxidizes organics electrochemicallly at low temperatures and pressures. The useful process can be used to treat mixed wastes containing hazardous organics. This paper have studied MEO of ethylene glycol (EG) in nitric acids by Fe(III)/Fe(II) and Co(III)/Co(II) system. It investigated current density, supporting electrolyte concentration, hydraulic retention time, removal efficiency of EG by MEO. Removal efficiency of EG by MEO was superior in Co(III)/Co(II) redox system than Fe(III)/Fe(II) redox system, where MEO removal efficiency was 100 percent. In case of EG, the reactions were fast and good yields of carbon dioxide formation was observed.

• Polymer(Korea)
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• v.24 no.3
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• pp.382-388
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• 2000

Polymer electrolyte films consisting of poly(vinylidenefluoride-hexafluoropropylene) (PVdF-HFP), LiClO$_3$ and a mixture of ethylene carbonate (EC) and ${\gamma}$-butyrolactone (GBL) were examined in order to obtain the best compromise between high ionic conductivity, homogeniety, dimensional and electrochemical stability. Measurements of ionic conductivity, differential scanning calorimetry and linear sweep voltammetry have been carried out for various compositions. The highest conductivity of 3.8$\times$10$^{-3}$ S$cm^{-1}$ / at 3$0^{\circ}C$ were obtained for a film of 30(PVdF-HFP)+7.8LiClO$_4$+62.2EC/GBL. From the DSC study, it has been found that the PVdF-HFP gels are stable up to 10$0^{\circ}C$, and the salt lowers the melting temperature of crystalline part of PVdF by interacting sensitively with polymer segments. When Lithium metal is in contact with the gel films, it tends to undergo corrosion and the reaction products accumulate resulting in the formation of a passive film on Li electrode. As the aging time progresses, the interfacial resistance increases continuously. Anodic stability is measured to extend up to about 4.5 V vs. Li.