• Journal of Electrochemical Science and Technology
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• 제10권2호
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• pp.104-114
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• 2019

Energy is an essential driving force for modern society. In particular, electricity has become the standard source of power for almost every aspect of life. Electric power runs lights, televisions, cell phones, laptops, etc. However, it has become apparent that the current methods of producing this most valuable commodity combustion of fossil fuels are of limited supply and has become detrimental for the Earth's environment. It is also self-evident, given the fact that these resources are non-renewable, that these sources of energy will eventually run out. One of the most promising alternatives to the burning of fossil fuel in the production of electric power is the proton exchange membrane (PEM) fuel cell. The PEM fuel cell is environmentally friendly and achieves much higher efficiencies than a combustion engine. Water management is an important issue of PEM fuel cell operation. Water is the product of the electrochemical reactions inside fuel cell. If liquid water accumulation becomes excessive in a fuel cell, water columns will clog the gas flow channel. This condition is referred to as flooding. A number of researchers have examined the water removal methods in order to improve the performance. In this paper, a new water removal method that investigates the use of vibro-acoustic methods is presented. Piezo-actuators are devices to generate the flexural wave and are attached at end of a cathode bipolar plate. The "flexural wave" is used to impart energy to resting droplets and thus cause movement of the droplets in the direction of the traveling wave.

• 한국전기화학회:학술대회논문집
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• 한국전기화학회 2000년도 춘계총회 및 학술발표회
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• pp.17-17
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• 2000

• 상하수도학회지
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• 제33권1호
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• pp.31-41
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• 2019

Volatile organic compounds(VOCs) are toxic carcinogenic compounds found in wastewater. VOCs require rapid removal because they are easily volatilized during wastewater treatment. Electrochemical advanced oxidation processes(EAOPs) are considered efficient for VOC removal, based on their fast and versatile anodic electrochemical oxidation of pollutants. Many studies have reported the efficiency of removal of various types of pollutants using different anodes, but few studies have examined volatilization of VOCs during EAOPs. This study examined the removal efficiency for VOCs (chloroform, benzene, trichloroethylene and toluene) by oxidization and volatilization under a static stirred, aerated condition and an EAOP to compare the volatility of each compound. The removal efficiency of the optimum anode was determined by comparing the smallest volatilization ratio and the largest oxidization ratio for four different dimensionally stable anodes(DSA): Pt/Ti, $IrO_2/Ti$, $IrO_2/Ti$, and $IrO_2-Ru-Pd/Ti$. EAOP was operated under same current density ($25mA/cm^2$) and electrolyte concentration (0.05 M, as NaCl). The high volatility of the VOCs resulted in removal of more than 90% within 30 min under aerated conditions. For EAOP, the $IrO_2-Ru/Ti$ anode exhibited the highest VOC removal efficiency, at over 98% in 1 h, and the lowest VOC volatilization (less than 5%). Chloroform was the most recalcitrant VOC due to its high volatility and chemical stability, but it was oxidized 99.2% by $IrO_2-Ru/Ti$, 90.2% by $IrO_2-Ru-Pd/Ti$, 78% by $IrO_2/Ti$, and 75.4% by Pt/Ti anodes The oxidation and volatilization ratios of the VOCs indicate that the $IrO_2-Ru/Ti$ anode has superior electrochemical properties for VOC treatment due to its rapid oxidation process and its prevention of bubbling and volatilization of VOCs.

• 환경위생공학
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• 제11권3호
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• pp.37-46
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• 1996

In this study, the effect of pH, Temp, dye concentration, distance of electrode, and the potential on the removal efficiency of dye-wastewater using electrochemical reaction were investigated. Optimum conditions for the electrochemical treatment of dye-wastewater were obtained that pH;7, 8V, electrode distance; 1cm and the reaction time for obtaining above 99% removal efficiency were 10 - 40min at each conditions, From this result, we can determine the instantaneous current efficiency and specific energy consumption, and we can provide the effective data for economical treatment of industrial dye-wastewater.

• 한국환경보건학회지
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• 제34권6호
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• pp.439-445
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• 2008

The feasibility study for the application of the removal and mineralization of Rhodamine B (RhB) was performed in a batch electrochemical reactor. The electro/UV process was consisted of DSA (dimensionally stable anode) electrode and UV-C or ozone lamp. The experimental results showed that RhB removal by the ozone lamp was higher than that of the UV-C lamp. Optimum current of the electro/UV process was 1 A. The electrochemical, UV and electro/UV process could completely degrade RhB, while a prolonged treatment was necessary to reach a high level RhB mineralization. It was observed that RhB removal in electro/UV process is similar to the sum of the UV and electrolytic decolorization. However, it was found that the COD of RhB could be degraded more efficiently by the electro/UV process (90.2 %) than the sum of the two individual oxidation processes [UV (19.7%) and electrolytic process (50.8%)]. A synergetic effect was demonstrated between the UV and electrolysis.

• 분석과학
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• 제19권4호
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• pp.316-322
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• 2006

The removal efficiencies of silver-ACFs were associated with their surface properties such as surface area, porosity, and the electro-chemical reaction time for the silver treatments. X-ray diffraction patterns of fibers electrochemically treated with silver display diffraction peaks for metallic silver and kinds of silver chloride complexes on the fiber surface after electrochemical adsorption. The results of SEM and EDX indicate that surface reaction motive of silver-ACF prepared by electrochemical reaction are depend on time function for the chloride ion removal efficiency. Finally, Cl ion adsorbed by the silver-ACFs from the ICP analysis seems to show an excellent removal effect.

• Journal of Electrochemical Science and Technology
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• 제8권2호
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• pp.124-132
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• 2017

The performance of electrolytic processes using copper and catalyzed electrodes for enhanced nutrient removal with various catalyzers and combinations of electrodes was evaluated. The catalyzed electrodes removed more ammonia nitrogen than the copper electrode, but higher ammonia removal was achieved using a Pt/Ti anode. On the other hand, electrolysis using the Pt/Cu anode consumed less energy and cost less. During electroreduction, nitrate was better removed by a pair of copper electrodes than by the catalyzed electrodes. During electrolysis of synthetic wastewater, ammonia removal not only increased owing to direct oxidation at the anode, but was also influenced by indirect oxidation at the cathode. Platinum-coated copper and titanium cathodes actively produced oxidizers and thus removed more ammonia than a pure metal cathode. Although phosphorus was removable irrespective of the type of catalyzer, electrocoagulation using the copper electrode achieved complete removal of phosphorus in a period of less than 10 min.

• 한국환경농학회지
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• 제19권2호
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• pp.134-141
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• 2000

전기화학적 방법을 이용한 농공단지폐수의 효율적인 처리기술개발을 위한 기초실험으로서 전압, 전극판 간격, pH 및 전해용액 주입농도 등에 따른 오염물질 처리효율을 조사한 결과는 다음과 같다. 전압별 전기화학반응조내 온도 및 pH는 전압이 높을수록 상승하였으나, EC는 전압별로 별 변화가 없었다. COD, 탁도, T-N 및 T-P의 처리율은 전압이 높을수록 증가하였으며 전압 20V일 경우 COD는 20분, 탁도는 30분, T-N 및 T-P는 2분일 때 각각 그 처리율이 약 65, 90, 68 및 84%로 가장 높았다. 전극판 간격별 COD 처리율은 전극간격이 좁아질수록 그리고 전기반응시간이 경과할수록 전반적으로 증가하는 경향이었으며, 탁도 처리율은 전극판 간격 모두 전기반응초기에 약 80%이상 처리되었고, T-N 처리율은 전극판 간격이 좁을수록 높았다. T-P 처리율은 전기반응시간 2분 후에 전극판 간격 모두에서 약 79% 이상 처리되었다. 초기 pH에 따른 COD 처리율은 전반적으로 pH 7에서 높았으며, 탁도 처리율은 전기반응시간 2분 이후의 모든 조건에서 약 80%이상 처리되었다. 그리고 T-N 처리율은 초기 pH가 높아질수록 증가하였고, T-P 처리율은 전기반응시간 2분 이후 초기 $pH\;5{\sim}9$에서 약 $79{\sim}96%$로서 가장 높았다. NaCl 농도별 오염물질 처리율은 전반적으로 NaCl을 주입한 경우가 NaCl를 주입하지 않은 경우에 비해 매우 높았으며, COD 및 T-P의 처리율은 $NaCl\;500mg/l$, 탁도 처리율은 $NaCl\;1,000mg/l$, T-N의 처리율은 NaCl 250 및 $500mg/l$에서 전반적으로 다른 조건에 비하여 높았다.

• 공업화학
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• 제16권2호
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• pp.206-211
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• 2005

백금과 티탄늄-이리듐전극으로 0.5 M의 철(II)과 코발트(II) 이온을 함유한 8.0 M의 질산용액 중에서 분자량이 1000, 4000, 20000인 폴리에틸렌글리콜류의 매개전해산화를 하였다. Fe(III)/Fe(II)와 Co(III)/Co(II) 산화환원계를 이용하여 전류밀도, 전극종, 전해질농도, 제거효율 등을 검토하였다. 백금전극 상에서 $0.67A/cm^2$의 전류밀도로 180~210 min 간 Fe(III)/Fe(II)와 Co(III)/Co(II) 전해환원계에서 매개전해산화에 의하여 폴리에틸렌글리콜류는 탄산가스로 분해되었다. 매개전해산화시 폴리에틸렌글리콜류의 제거효율은 Fe(III)/Fe(II) 산화환원계보다 Co(III)/Co(II) 산화환원계가 우수하였고 분자량이 1000, 4000, 20000인 폴리에틸렌글리콜류의 매개전해산화 제거효율은 100%이었다.

• Advances in nano research
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• 제13권6호
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• pp.513-525
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• 2022

In this study, it was aimed to evaluate direct oxidation of aqueous solution containing cefalexin antibiotic with new generation Sn/Sb/Ni: 500/8/1 anode. The fact that there is no such a study on treatment of cefalexin with these new anode made this study unique. According to the operating parameters evaluation COD graphs showed clearer results compared to TOC and CLX and thus, it was it was chosen as major parameter. Furthermore, pseudo-first degree kd values were calculated from CLX results to show more accurate and specific results. Experimental results showed that after 60 min of electrochemical oxidation, complete removal of COD and TOC was accomplished with 750 mg L^-1 KCl, at pH 7, 50 mA cm^-2 current density and 1 cm anode-cathode distance. Also, the stability of the Sn/Sb/Ni anode was evaluated by taking SEM and AFM images and XRD analysis before and after of electrochemical oxidation processes. According to the results, it was not occurred too much change on the anode surface even after 300 h of electrolysis. Thus, it was thought that the anode material was not corroded to a large extent. Furthermore, the removal efficiencies were very high for almost all the time and conditions. According to the results of the study, electrochemical oxidation with new generation Sn/Sb/Ni anodes for the removal of cefalexin antibiotic was found very successful and applicable due to require less reaction time complete mineralization and doesn't require pH adjustment step compared to other studies in literature. In future studies, different antibiotic types should be studied with this anode and maybe with real wastewaters to test applicability of the process in treatment of pharmaceutical wastewaters containing antibiotics, in a better way.