• 공업화학
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• 제21권6호
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• pp.697-701
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• 2010

팔라듐을 연료극 촉매로 이용한 개미산 연료전지에서의 성능과 팔라듐 촉매의 전기화학적 특성 분석을 수행하였다. 연구를 위해 사용된 팔라듐 촉매는 직접페인트법에 의해 제조되어 전해질 위에 코팅되었다. 개미산 연료전지를 연속적으로 반복 운행 했을 때, 팔라듐 촉매의 활성 및 개미산 연료전지의 분극 곡선 성능이 지속적으로 감소하였다. 이러한 거동은, 연료전지의 운행동안 팔라듐 촉매와 포매이트 및 수산화 이온간 전기화학적 반응에 의한 결합에 따른 팔라듐 촉매의 활성 저하 때문인 것으로 생각된다. 이러한 팔라듐 촉매의 활성 저하를 설명하고, 팔라듐 촉매와 개미산 연료전지의 활성을 되살리려는 실험이 선형 전압 인가법에 의해 수행되었다. 1.0볼트의 최대 전압을 가진 역방향 선형전압 인가 실험 후에 팔라듐 촉매의 활성 및 개미산 연료전지의 분극 곡선 성능이 되살아났다. 이는 역방향 선형 전압 인가법에 의해, 포매이트 및 수산화 이온들과의 결합되어 있던 팔라듐 촉매의 결합이 끊어지면서 팔라듐 촉매의 활성이 되살아났기 때문인 것으로 분석되었다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.482-488
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• 2001

Platinum group metals (pgm) are useful to many industries such as chemical, dental and medical, petroleum, refining, electrical and electronic, and automotive. Researchers at the South Dakota School of Mines and Technology and PGM Recovery Ltd. have developed jointly an environmentally sound and metallurgically efficient process for extracting these metals from secondary sources. Once these metals have been dissolved in the leach liquor, the individual metals mainly platinum, palladium, and rhodium, should be separated in order to recover the individual metals with high purity. During this investigation, solvent extraction has been chosen as the method used to achieve the separation and extraction of platinum, palladium, and rhodium from the leach liquor. There were three solutions used throughout this procedure: 1) Synthetic solution (200 ppm Pt 80 ppm Pd 20 ppm Rh; 300 ppm Pt, 180 ppm Pd 50 ppm Rh), and 2) Auto catalyst leach liquors (100 ppm Pt, 30 ppm Pd, 20 ppm Rh). The solvents investigated included Lix 84(2-hydroxy-5-nonylacetonphenone oxime in a mixture with 5-dodecylsalicyloxime), Lix 84-I, ACORGA CLX-50 (diester of pyridine 3,5 dicarboxylic acid), and di-hexyl sulfide. The extraction values achieved using ACORGA CLX-50, Lix 84, and Lix 84-I were respectively Pt (25%, 0% 0%), Pd (100%, 99.8%, 95.3%), and Rh (99.1%, 35.5%, 4.25%). The stripping processes for the Lix 84, and Lix 84-I were proven to be more involved than others. The solutions were required to be simultaneously heated and stirred. The percentages acquired through these processes yielded unsatisfactory results. The stripping procedure for the ACORGA CLX-50 was easier to execute, yet the percentage recovered from this process was also unsatisfactory. Overall the di-hexyl sulfide has proved to be the most successful organic for this procedure. The average percent extracted for palladium was excellent with 99.9% - 100% with very little Platinum and rhodium extracted. The ability of stripping palladium in ammonia solution was also found to be excellent.

• Bulletin of the Korean Chemical Society
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• 제33권8호
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• pp.2623-2626
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• 2012

A series of functionalized furans were synthesized by way of a palladium-catalyzed coupling reaction of 2,3,5-trisubstituted furans with aryl chlorides through C-H bond cleavages at C-4 position. The feature of the reaction was facilitative preparation of furan derivatives with good functional group tolerance. All reactions gave the desired products in moderate to good yields in the presences of $BuAd_2P$ and t-BuOK in DMF at $120^{\circ}C$ after 15 h.

• 대한화학회지
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• 제27권6호
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• pp.441-448
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• 1983

여러가지 브롬화비닐 화합물들 ((Z)-1-bromopropene, 1-bromo-2-methylpropene, 2-bromo-3-methyl-2-butene, (E)-ethyl 2-methyl-3-bromo-2-propenoate, 1-bromo-cyclohexene)과 올레핀 화합물인 ethyl acrylate, methyl methacrylate, ethyl crotonate, allyl cyanide, ethyl 3-butenoate, ethyl 4-pentenoate와 methyl 10-undecenoate를 palladium acetate촉매와 triorthotolyphosphine 및 triehylamine존재 하의 수득율로 얻었으며 이들 생성물의 입체화학도 규명하였다. 위의 방법을 이용하므로써 ethyl 3-butenoate, ethyl 4-pentenoate와 methyl 10-undecenoate에 의한 4개, 5개 및 11개 탄소-탄소 결합의 확장도 가능하였다.

• 대한화학회지
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• 제29권3호
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• pp.287-294
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• 1985

Acrylamide, N-alkyl substituted acrylamides and N,N-diethylacrylamide를 트리에틸아민과 palladium acetate-triorthotolyl phosphine 촉매 존재하에서 브롬화 방향족화합물들과 비닐화 반응을 실시하여 여러 기능기로 치환된 aryl conjugated enamides를 합성하였다. 이들 반응은 모두 선택적으로 진행되어 (E)-이성질체의 aryl conjugated enamides를 생성하였다. N-alkyl substituted acrylamides는 브롬화 방향족화합물들과의 반응에서 acrylamide와 N,N-diethylacrylamide보다 더 좋은 반응성을 나타내어 생성물들을 높은 수득율로 얻을 수 있었다. 또한 브롬화 방향족화합물이 전자받기 기능기로 치환된 경우에 좋은 반응성을 나타냈으며 전자 주기 기능기를 갖는 경우 acrylamide와 N,N-diethylacrylamide와의 반응에서는 반응이 전혀 진행되지 않거나 낮은 반응성을 나타냈다.

• Bulletin of the Korean Chemical Society
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• 제24권2호
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• pp.225-228
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• 2003

• 한국응용과학기술학회지
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• 제25권3호
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• pp.291-298
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• 2008

Although the pyrimidine derivatives were obtained in low yields ranging from 8% to 20%, we reported the successful preparation of N,N-diaryl-pyrimidin-2-amine derivatives starting from the corresponding 2-aminopyrimidines (1a-1c), by direct palladium-catalyzed arylation using different arylbromides. The reasons of low yields are thought to be the electronic and steric effects by the neighboring aromatic systems. The absorption spectra and photoluminescent spectra of compounds (3a 3g and 4a-4c) were measured using dichloromethane on the concentration of 25 mM by UV vis spectroscopy and luminescent spectroscopy. Pyrimidine derivatives 4a, 4b, and 4c showed moderate emission maxima at 474 nm, 481 nm, and 367 nm, respectively, while other compounds showed very weak photoluminescence or no photoluminescence at all.

• Archives of Pharmacal Research
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• 제27권2호
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• pp.136-142
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• 2004

In this study, a highly diastereoselective synthesis of anti-1 ,2-aminoalcohol was explored starting from L-amino acids as chiral sources. The higher yield and diastereoselectivity was shown when the aza-Claisen rearranqement was performed with allylic trichloroacetimidate 6a in the presence of palldium(II) catalyst.

• Advances in nano research
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• 제3권2호
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• pp.67-79
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• 2015

Air stable nanoparticles were prepared from cobalt sulphate using tetra butyl ammonium bromide as surfactant and sodium borohydride as reductant at room temperature. The cobalt nanocolloids in aqueous medium were found to be efficient catalysts for the degradation of toxic organic dyes. Our present study involves degradation of Methylene Blue and Rhodamine-B using cobalt nanoparticles and easy recovery of the catalyst from the system. The recovered nanoparticles could be recycled several times without loss of catalytic activity. Palladium nanoparticles prepared from palladium chloride and the same surfactant were found to degrade the organic dyes effectively but lose their catalytic activity after recovery. The cause of dye colour discharge by nanocolloids has been assigned based on our experimental findings.

• 한국수소및신에너지학회논문집
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• 제27권3호
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• pp.264-269
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• 2016

A simple dry chemical approach was developed in order to load palladium (Pd) as a promoter on Pt/gas diffusion electrode (GDE) for polymer electrolyte membrane fuel cell (PEMFC). Palladium(II) bis (acetylacetonate), $Pd(acac)_2$ was sublimed, penetrated into Pt/GDE and then reduced to Pd nanoparticles simultaneously without any reducing agent and any solvent in a glass reactor of $N_2$ atmosphere at $180^{\circ}C$ for 3, 5 and 15 min. Pd distribution was analyzed by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS), and I-V curve was estimated by using a unit cell with $5{\times}5cm^2$ active area.