http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
박권필,조규진,이건직,전해수,Park Kwon Pil,Cho Gyou Jin,Lee Gun Jik,Chun Hai Soo 한국전기화학회 1999 한국전기화학회지 Vol.2 No.4
고분자전해질형 연료전지에서 에칭한 Nafion막으로 고분자막/전극 어셈블리를 제조하고 그 성능을 측정하였다. 에칭을 함으로서 고분자막과 전극의 접합이 잘 이루어져 hot pressing 압력과 온도를 낮출 수 있었고, 낮은 온도에서 hot pressing이 이루어짐으로서 전지의 성능을 향상시킬 수 있었다. 어셈블리 제조방법중의 하나인 페인팅 방법에서 에칭 된 Nafion막을 이용하면 전지의 성능이 향상됨을 보였으며, 에칭정도에 따라 적당한 양의 전극촉매를 사용해야 함을 보였다. Etched Nafion membrane and electrode assemblies were fabricated and those performances were observed in PEMFC. Adhesion of membrane to electrode increased with abrasion of membrane surface. Membrane surface ething results in reduction of hot pressing temperature, as a consequence, in improving of cell performance. It was found that Nafion etching was effective in painting method. The optimum content of electrode catalyst should be selected according to etching intensity.
PEMFC에서 전극 열화가 전해질 막 열화에 미치는 영향
박권필 ( Kwon Pil Park ),송진훈 ( Jin Hoon Song ),김세훈 ( Sae Hoon Kim ),안병기 ( Byung Ki Ahn ),고재준 ( Jai Joon Ko ) 한국화학공학회 2013 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.51 No.1
Until a recent day, degradation of PEMFC MEA (membrane and electrode assembly) has been studied, separated with membrane degradation and electrode degradation, respectively. But membrane and electrode were degraded coincidentally at real PEMFC operation condition. During simultaneous degradation, there was interaction between membrane degradation and electrode degradation. The effect of electrode degradation on membrane degradation was studied in this work. We compared membrane degradation after electrode degradation and membrane degradation without electrode degradation. I-V performance, hydrogen crossover current, fluoride emission rate (FER), impedance and TEM were measured after and before degradation of MEA. Electrode degradation reduced active area of Pt catalyst, and then radical/H2O2 evolution rate decreased on Pt. Decrease of radical/H2O2 reduced the velocity of membrane degradation.
Co-P-B/FeCrAlloy 촉매를 이용한 NaBH_4 가수분해 반응
박권필 ( Kwon Pil Park ),황병찬 ( Byung Chan Hwang ),조아라 ( A Ra Jo ),신석재 ( Suk Jae Sin ),최대기 ( Dae Ki Choi ),남석우 ( Suk Woo Nam ) 한국화학공학회 2013 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.51 No.1
Properties of NaBH_4 hydrolysis reaction using Co-P-B/FeCrAlloy catalyst and the catalyst durability were studied. Co-P-B/FeCrAlloy catalyst showed low activation energy such as 25.2 kJ/mol in 5 wt% NaBH_4 solution, which was similar that of noble metal catalyst. The activation energy increased as the NaBH_4 concentration increased. Formation of gel at high concentration of NaBH_4 seriously affected hydrogen evolution rate and the catalyst durability. The catalyst loss decreased as reaction temperature increased due to lower gel formation when the concentration of NaBH_4 was over 20 wt%. Considering hydrogen generation rate and durability of catalyst, the catalyst supported with FeCrAlloy heat-treated at 1000℃ without ultra vibration during dipping and calcination after catalyst dipping was best catalyst. To use catalyst more than three times in 25 wt% NaBH_4 solution, it should be reacted at higher temperature than 60℃.
박권필 ( Kwon Pil Park ),신수철 ( Soo Cheol Shin ),안명원 ( Myeong Won Ahn ),이정식 ( Jung Shik Lee ),김영숙 ( Young Suk Kim ) 한국화학공학회 2013 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.51 No.1
Extraction process of fucoxanthin from Undaria pinnatifida and stability of fucoxanthin was studied. In this study, to utilized extracted components as a functional food material, ethanol was used as a solvent. The maximum concentration of fucoxanthin was obtained when 80% ethanol solvent was used. The extraction yield of fucoxanthin increased as extraction temperature raised to 50℃Water washing of raw material for 5 minutes reduced the salt content about 94%. From the experiment that fucoxanthin content reduced by 30% for 1 day storage at 70℃, it was demonstrated that fucoxanthin was thermal-unstable above 70℃. And experimental result of light- stability showed that fucoxanthin was very unstable with light.
가축 분뇨를 이용한 미생물 연료전지의 특성 및 MEA 열화
박권필 ( Kwon Pil Park ),김영숙 ( Young Sook Kim ),추천호 ( Cheun Ho Chu ),정재진 ( Jae Jin Jeong ),안명원 ( Myung Won Ahn ),나일채 ( Il Chai Na ),이정훈 ( Jeong Hoon Lee ) 한국화학공학회 2014 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.52 No.2
Microbial fuel cells (MFC) were operated with livestock wastes and PEMFC (Proton Exchange Membrane Fuel Cells) MEA (Membrane and Electrode Assembly). OCV of MFC with mixtures of microbial was higher than that of MFC with single microbial. MFC using pig wastes showed highest OCV (540 mV) among cow waste, chicken waste and duck waste. And the power density of MFC using pig waste was 963 mW/m2. Contamination of MEA withNa2+, Ca2+, K+ ion and impurities was the one cause for low performance of MFC during operation.
PEMFC 고분자 막의 전기화학적 열화과정에서 OCV 감소 및 회복 거동을 통한 비가역적 열화 연구
유동근 ( Donggeun Yoo ),박권필 ( Kwon-pil Park ) 한국화학공학회 2022 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.60 No.2
It is very important to analyze the OCV change behavior during the open circuit potential holding (OCV holding) process, which accelerates the evaluation of the electrochemical durability of the PEMFC membrane. In this study, an empirical formula using the experimental data of three MEAs with different durability was created and compared. The durability evaluation time of the reinforced membrane MEA without radical scavenger inside the membrane was 383 h, and the durability evaluation time of the reinforced membrane MEA with radical scavenger inside the membrane was 1,000 and 1,650 h, respectively. The degradation of the membrane was divided into the reversible degradation that can be recovered by activation and the irreversible degradation that is not recovered. The irreversible degradation of the membrane was indicated by an increase in hydrogen permeability, and the change in hydrogen permeability was similar to the irreversible degradation constant c of all three MEAs. The initiation of irreversible deterioration without recovery is indicated by an increase in hydrogen permeability, and the OCV is not recovered due to an increase in hydrogen permeability, so the slope of the OCV recovery line (ORL) decreases, which can be confirmed by an increase in the constant c value of the empirical formula.
이호(Lee, Ho),신강섭(Shin, Kang-Sup),박권필(Park, Kwon-Pil) 한국신재생에너지학회 2007 한국신재생에너지학회 학술대회논문집 Vol.2007 No.11
PEMFC의 상용화 진입에 있어서 걸림돌 중의 하나가 열화(degradation)에 의한 성능감소이다. PEMFC 고분자 막의 열화가 PEMFC 성능 감소에 많은 영향을 미친다. 고분자 막의 성능 감소 원인은 여러가지가 있지만 무가습/OCV조건에서 성능 감소가 잘 된다. 그 이유에 대해서는 OCV/무가습 조건에서 과산화수소나 라디칼이 많이 형성될 수 있다는 것과, OCV조건에서 사용되지 못하는 수소와 산소의 gas-crossover 가 많기 때문이라는 것 그리고 무가습 조건에서 수소와 산소의 분압이 높아 gas-crossover 가 유리하고 악의 건조에 따른 물리적인 영향 등등이 거론되고 있다. 본 연구에서는 같은 조건에서 Cell 운전온도가 막열화에 미치는 영향을 실험하였다. OCV 여려 조건 에서 단위전지 실험을 한 후 I-V, 수소 투과도, 임피던스, FER(fluoride emission rate)등을 측정해 그 결과를 검토 분석하였다. OCV/Anode 무가습 조건이 알려진 대로 막열화 가속조건 이었음을 확인하였고, 실험 결과 Cell 운전온도가 10?C증가 할 때마다 FER(fluroide emission rate)이 즉 막 열화속도가 약 2배정도 증가함을 보였다.
고분자전해질 연료전지에서 고분자 막과 전극의 철 이온 오염 및 산 세척 효과
유동근 ( Donggeun Yoo ),박민정 ( Minjeong Park ),오소형 ( Sohyeong Oh ),박권필 ( Kwon-pil Park ) 한국화학공학회 2022 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.60 No.1
In the process of long-term use of PEMFC (Proton Exchange Membrane Fuel Cells), chemical degradation of membrane electrode assembly (MEA) occurs due to corrosion of stack elements and contamination of supply gas. In this study, we investigated whether chemically degraded MEA can be recovered by acid washing. The performance was measured and compared in a PEMFC cell after contamination with iron ions and washing with an aqueous sulfuric acid solution. The performance was reduced by about 25% by 0.5 ppm iron ion contamination, and 97.1% performance recovery was possible by washing of 0.15 M sulfuric acid. The membrane resistance was increased due to iron ion contamination of the polymer membrane, and the ionic conductivity was restored by washing the iron ions from the membrane while minimizing the loss of the electrode catalyst by washing with a low-concentration sulfuric acid aqueous solution. The possibility of solving the decrease in durability caused by chemical contamination of PEMFC MEA by the acid washing was confirmed.