• Title/Summary/Keyword: palladium on carbon

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A Study of Carbon Monoxide Oxidation on Pt & Pt-Pd Catalysts (귀금속촉매 (Pt, Pd)를 이용한 일산화탄소 산화반응에 관한 연구)

  • 金京林
    • Journal of Korean Society for Atmospheric Environment
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    • v.1 no.1
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    • pp.43-51
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    • 1985
  • This study is concerned with the oxidation of carbon monoxide on platinum and platinum-palladium catalysts. Catalysts were made by the impregnation method and flow reactor was used in the catalytic reaction. As for the mixed gases, carbon monoxide concentration varied from 1 to 4% and that of oxygen from 1 to 4%. $N_2$ was used as carrier gas and GHSV varied from 24, 000 $h^{-1} to 60, h^{-1}$. The temperature range was from 200 to $600^\circ$C. It was also taken into consideration that the heat and mass transfer resistance of our catalysts was negligible in the study. Experimental results showed that platinum-palladium catalyst was about 1.5-3.9% superior to platinum catalyst in conversion yield. When we used platinum-palladium catalyst, we observed that carbon monoxide oxidation was found to be 1 st order with respect to carbon monoxide concentration. Activation energy of the catalyst was 23.5 kcal/mol.

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Synthesis of Diaryl $\alpha$-Diketones via Palladium Catalyzed Double Carbonylative Homo Coupling of Aryl Iodides with Carbon Monoxide

  • Kim Jin Il;Kim Nam Jung;Ryu Cheol Mo
    • Bulletin of the Korean Chemical Society
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    • v.9 no.1
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    • pp.30-32
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    • 1988
  • Symmetrical diaryl ${\alpha}-diketones$ were synthesized in moderately good yields through the palladium catalyzed reaction of aryl iodides with carbon monoxide. The reaction was tolerant of a wide variety of fuctionalities($OCH_3,\;CH_3,\;NO_2,\;OH,\;COOH$) on the aryl iodide. On the other hand, the similar reaction of aryl bromides or chlorides with carbon monoxide did not proceed.

Hybrid Nanocomposites of Palladium Nanoparticles Having POSS and MWNTs via Ionic Interactions

  • Jeon, Jong-Hwan;Lim, Jung-Hyurk;Kim, Kyung-Min
    • Macromolecular Research
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    • v.17 no.12
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    • pp.987-994
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    • 2009
  • Palladium nanoparticles having cubic silsesquioxanes (POSS) (Pd-POSS) were produced by the reaction of palladium (II) acetate and octa(3-aminopropyl)octasilsesquioxane octahydrochloride (POSS-${NH_3}^+$ in methanol at room temperature. Functionalized multiwalled carbon nanotubes (MWNT-COOH) were prepared by acid treatment of pristine MWNTs. The hybrid nanocomposites of Pd-POSS and MWNT-COOH (Pd-MWNT nanocomposites) were synthesized by self-assembly method via ionic interaction between positively charged Pd-POSS and negatively charged MWNT-$COO^-$. The spherical aggregates of Pd-POSS with a diameter of 40-60 urn were well attached to the surfaces of MWNT-COOH on Silicon wafer. The composition, structure, and surface morphology of Pd-MWNT nanocomposites were studied by UV-vis spectrophotometer, energy dispersive spectrum (EDX), scanning electron microscopy (SEM), and atomic force microscope (AFM).

Pd(II) Catalyzed Copolymerization of Styrene and CO in Quaternary Ammonium Ionic Liquids

  • Tian, Jing;Guo, Jin-Tang;Zhu, Cheng-Cai;Zhang, Xin;Xu, Yong-Shen
    • Macromolecular Research
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    • v.17 no.3
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    • pp.144-148
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    • 2009
  • Poly(1-oxo-2-phenyltrimethylene) was synthesized by palladium-catalyzed copolymerization of styrene and carbon monoxide in quaternary ammonium ionic liquids. The $[Pd(bipy)_2][PF_6]_2$ compound had relatively more catalytic activity than $[Pd(bipy)_2][BF_4]_2$ in ionic liquids. The catalytic activity of palladium (II) composite catalyst was superior to the catalyst formed in situ from palladium acetate, 2,2-bipyridyl, and $X^-$ ($X^-=PF_6^-$, $BF_4^-$) in ionic liquids. The effects of the volume of ionic liquids, reaction time and benzoquinone content on the copolymerization were also described.

DEVELOPMENT OF ANODIC STRIPPING VOLTAMMETRY FOR THE DETERMINATION OF PALLADIUM IN HIGH LEVEL NUCLEAR WASTE

  • Bhardwaj, T.K.;Sharma, H.S.;Jain, P.C.;Aggarwal, S.K.
    • Nuclear Engineering and Technology
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    • v.44 no.8
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    • pp.939-944
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    • 2012
  • Deposition potential, deposition time, square wave frequency, rotation speed of the rotating disc electrode, and palladium concentration were studied on a Glassy Carbon Electrode (GCE) in 0.01M HCl for the determination of palladium in High Level Nuclear Waste (HLNW) by anodic stripping voltammetry. Experimental conditions were optimized for the determination of palladium at two different, $10^{-8}$ and $10^{-7}M$, levels. Error and standard deviation of this method were under 1% for all palladium standard solutions. The developed technique was successfully applied as a subsidiary method for the determination of palladium in simulated high level nuclear waste with very good precision and high accuracy (under 1 % error and standard deviation).

Development of Hexafluoropropylene Hydrogenation with Pd/C Particles Prepared with 1-Hexyl-3-methylimidazolium Tetrafluoroborate (1-Hexyl-3-methylimidazolium Tetrafluoroborate으로 제조된 팔라듐 탄소촉매를 이용한 Hexafluoropropylene 수소화 반응)

  • Jeong, Ji Baek;Yoo, Kye Sang
    • Applied Chemistry for Engineering
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    • v.24 no.4
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    • pp.412-415
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    • 2013
  • Palladium on carbon powder was prepared using 1-hexyl-3-methylimidazolium tetrafluoroborate, one of room temperature ionic liquids. The synthesized particles were tested as a hexafluoropropylene hydrogenation catalyst. Moreover, the hydrogenation was performed under various reaction conditions to develop an optimum reaction process. The catalyst prepared by more than 3 wt% of palladium and the unity mole ratio of ionic liquid to palladium precursor showed higher catalytic activity. For reaction conditions, the complete hexafluoropropylene (HFP) conversion was achieved at these conditions; the volume flow ratio of hydrogen to HFP was higher than 1.25 and $GHSV_{HFP}$ was lower than 50000 mL/g-h.

Alternative Eletroless Copper Plating Process Utilizing Silver Catalyst on Poly(Ethylene Terephthalate) (PET위 Silver Catalyst를 이용한 무전해 구리 도금 대안 공정)

  • Lee, Hong-Gi;Heo, Jin-Yeong;Im, Yeong-Saeng;Lee, Geon-Hyeong
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2014.11a
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    • pp.127-128
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    • 2014
  • 현재 기술 산업에서 PET위 무전해 도금을 실행하기 위해 다양한 전처리 공정과 Catalyst가 소개되고 있다. 그 중에서 가장 일반적으로 사용되고 있는 Catalyst는 Palladium으로서 Tin과 산화 환원 반응으로 Electroless Copper Deposition 단계에서 구리 도금의 Target으로 작용하고 있다. 하지만 상대적으로 Palladium은 생산 비용이 높으며 Tin은 쉽게 산화되는 문제점이 남아 있다. 이를 대체하기 위한 대안 공정으로서 Palladium 대신 Silver를 이용하여 Catalyst로서의 역할을 하는 공정이다. 이전에 PET위 전처리 공정으로 Ultra Violet을 사용하여 표면을 개질 시키는 방법을 연구했으며, 그 후 Potassium Permanganate와 Silver Catalyst의 Mechanism을 연구 했다. PET 표면 개질을 거치면서 화학 구조가 바뀌어 표면에 Carbon Carbon Double Bond를 형성한다. 이때 Permanganate ion이 새로이 형성된 이중 결합과 반응하여 두 개의 extra-OH functional group을 생성함과 동시에 $MnO_2$를 만들어 표면에 흡착 시킨다. $MnO_2$는 전위차에 의해 Silver Ion과 Redox Reaction을 일으키며 실질적인 Catalyst 역할을 하게 된다. Silver Catalyst는 무전해 구리 도금 용액 안에서 Copper의 Target으로 작용한다.

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Synthesis of 2-Substituted Benzofurans from o-Iodophenols and Terminal Alkynes with a Recyclable Palladium Catalyst Supported on Nano-sized Carbon Balls under Copper- and Ligand-Free Conditions

  • Yum, Eul Kgun;Yang, Ok-Kyung;Kim, Ji-Eun;Park, Hee Jung
    • Bulletin of the Korean Chemical Society
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    • v.34 no.9
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    • pp.2645-2649
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    • 2013
  • We have developed a one-step synthesis of benzofurans from o-iodophenol and various terminal alkynes, by using Pd catalyst supported on nano-sized carbon balls (NCB) under copper- and ligand free conditions. This recyclable catalyst could be reused more than 5 times in the same heteroannulation reaction. The results have demonstrated that diverse 2-substituted benzofurans with tolerant functional groups can be prepared simply and conveniently under these conditions.

Preparation of Palladium on Carbon for Hydrogenation Catalyst Using [Bmim][$CF_3SO_3$] as an Effective Solvent (기능성 용매인 [Bmim][$CF_3SO_3$]를 이용한 수소화반응용 탄소 담지 팔라듐 촉매 제조)

  • Tae, Hyunman;Jeon, Seung Hye;Yoo, Kye Sang
    • Applied Chemistry for Engineering
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    • v.24 no.1
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    • pp.82-86
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    • 2013
  • Palladium particles were synthesized with 1-buthyl-3-methylimidazolium trifluoromethanesulfonate ([Bmim][$CF_3SO_3$]) as an effective solvent during the synthesis. The morphology of the particles was affected by the concentration of [Bmim][$CF_3SO_3$]. Furthermore, the palladium on carbon powder was prepared with various [Bmim][$CF_3SO_3$] concentrations and calcinations temperatures as a catalyst for hexafluoropropylene hydrogenation. Catalytic activity was varied by both conditions significantly. Under the identical condition, the catalyst prepared by the same mole ratio of [Bmim][$CF_3SO_3$] and palladium, and calcined at $500^{\circ}C$ was the most active in this reaction.