• 제목/요약/키워드: sodium borohydride

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$NaBH_4$ 수용액 분해 수소 발생용 최적 촉매 개발 (Development of an Catalyst for Hydrolysis of Aqueous Sodium Borohydride Solution)

  • 양태현;;이원용;김창수
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2005년도 춘계학술대회
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    • pp.296-298
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    • 2005
  • Hydrogen generation by the hydrolysis of aqueous sodium borohydride $(NaBH_4)$ solutions was studied using IRA-400 anion resin dispersed Pt. Ru catalysts and Lithium Cobalt oxide $(LiCoO_2)$ supported Pt, Ru and PtRu catalysts. The performance of the $LiCoO_2$ supported catalysts is better than the ion exchange resin dispersed catalysts. There is a marked concentration dependence on the performance of the $LiCoO_2$ supported catalysts and the hydrogen generation rate goes down if the borohydride concentration is increased beyond $10\%$. The efficiency of PtRu- $LiCoO_2$ is almost double that of either Ru-$LiCoO_2$ or Pt-$LiCoO_2$ for $NaBH_4$ concentrations up to $10\%$.

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직접 수소화붕소나트륨/과산화수소 연료전지의 산화극 연료 조성에 관한 연구 (A Study on Anode Fuel Composition of Direct Borohydride/Hydrogen Peroxide Fuel Cell)

  • 이태훈;유수상;오택현
    • 한국수소및신에너지학회논문집
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    • 제32권6호
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    • pp.514-523
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    • 2021
  • This study investigated the effect of anode fuel composition on the performance of direct borohydride/hydrogen peroxide fuel cells (DBHPFCs). The effect of sodium borohydride (NaBH4) and sodium hydroxide (NaOH) concentrations on fuel cell performance was determined through fuel cell tests. Fuel cell performance increased with an increase in the NaBH4 concentration, whereas it decreased with an increase in the NaOH concentration. The anode fuel composition was selected as 10 wt% NaBH4+10 wt% NaOH+80 wt% H2O based on the fuel viscosity, electrochemical reaction rate, and decomposition reaction rate. DBHPFCs were also tested to analyze the effect of operating temperature and operation time on fuel cell performance. The present results can be used as a reference basis to determine operating conditions of DBHPFCs.

고농도 과산화수소와 수소화물의 지속적인 반응에 대한 연구 (Feasibility of Energy Generation from Chemical Reaction between Hydrogen Peroxide/Hydride)

  • 서성현
    • 한국수소및신에너지학회논문집
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    • 제26권3호
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    • pp.271-277
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    • 2015
  • The present paper discusses about noble idea on various reactions including hydrides, hydrogen peroxide and nano-sized metal powders, which do not emit toxic materials as well as carbon dioxide. Here in this paper, the very first-ever concept that heat energy can be generated from the direct reaction between sodium borohydride and hydrogen peroxide is presented. Sodium hydride as fuel can supply hydrogen reacting with oxygen provided by the decomposition of hydrogen peroxide solution. Solid sodium borohydride can be resolved in water and treated as liquid solution for the easy handling and the practical usage although its solid powder can be directly mixed with hydrogen peroxide for the higher reactivity. The thermodynamic analysis was conducted to estimate adiabatic reaction temperatures from these materials. The preliminary experiment on the reactions conducted using sodium borohydride powder and hydrogen peroxide water solution revealed that the self-propagating reaction can occur and that its reactivity increases with an increase of hydrogen peroxide concentration.

Two Phase Reduction of Carbonyl Compounds with Sodium Borohydride

  • Jin Soon Chong;Nung Min Yoon
    • 대한화학회지
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    • 제15권3호
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    • pp.117-120
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    • 1971
  • Possibility of two phase reduction of carbonyl compounds to the corresponding alcohols was studied. Thus the 0.5 M ether solutions of the representative carbonyl compounds were treated with alkaline stabilized sodium borohydride aqueous solution at room temperature. Butyraldehyde was reduced rapidly within one hr., whereas other aldehydes tested; heptaldehyde, benzaldehyde, and 1-naphthaldehyde were reduced in 6-12 hr. 2-Heptanone was reduced much slowly; 87% in 48 hr., however, acetophenone was reduced moderately; 92% in 12 hr. and cycloalkanones were reduced rapidly (cyclohexanone in 0.5 hr., and cyclopentanone in 3-6 hr.).

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One-Pot Reductive Amination of Carbonyl Compounds Using Sodium Borohydride-Cellulose Sulfuric Acid

  • Alinezhad, Heshmatollah;Tollabian, Zakieh
    • Bulletin of the Korean Chemical Society
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    • 제31권7호
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    • pp.1927-1930
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    • 2010
  • A fast, efficient, and high yielding method for the preparation of amines by reductive amination of aldehydes and ketones using sodium borohydride in the presence of cellulose sulfuric acid in EtOH and under solvent-free conditions at room temperature is described.

Mild and Efficient Reduction of α,β-Unsaturated Carbonyl Compounds, α-Diketones and Acyloins with Sodium Borohydride/Dowex1-x8 System

  • Zeynizadeh, Behzad;Shirini, Farhad
    • Bulletin of the Korean Chemical Society
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    • 제24권3호
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    • pp.295-298
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    • 2003
  • α,β-Unsaturated aldehydes and ketones are regioselectively reduced to the corresponding allylic alcohols with /Dowex1-x8 system in THF at room temperature. This system is also efficient for the conversion of α-diketones and acyloins to the vicinal diols in refluxing THF.

$NaBH_4$를 이용한 소형연료전지용 수소저장시스템 개발 (The Hydrogen Generation System Using Sodium Borohydride for Small Fuel Cells)

  • 강순기;한기철;조준배;박태희;유용호
    • 한국전기화학회:학술대회논문집
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    • 한국전기화학회 2004년도 수소연료전지공동심포지움 2004논문집
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    • pp.129-134
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    • 2004
  • 문헌 연구를 통해 최적의 수소저장물질의서 수소저장 효율, 물질의 안정성 및 경제성이 우수한 나트륨붕소수소화물($NaBH_4$, sodium borohydride)을 선정하여, 소형연료전지용 수소저장시스템에 대한 다양한 특성을 조사하였다. $NaBH_4$의 기초 물성 조사를 위해 수소 발생 능력, 용해도, 수소 비발생 등의 실험을 수행하였으며 다양한 촉매의 특성비교는 물론 수소저장시스템의 설계시 핵심적으로 고려할 수 있는 Key factor의 특성을 파악하였다.

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Kinetic Studies on the Reduction of 1-Benzyl-3-cyanoquinolinium Cations by Sodium Borohydride and the Applicability Marcus Theory

  • Han, In-Sook;Lee, Chang-Kiu;Han, In-Sup
    • Bulletin of the Korean Chemical Society
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    • 제8권2호
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    • pp.79-83
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    • 1987
  • The reduction of a series of 1-substituted benzyl-3-cyanoquinolinium ions (p-$cH_3$, H, p-Br, m-F, p-CN) by sodium borohydride has been investigated. In all cases the products from these reactions were found to be 1, 2-dihydroquinolines over 82% yields. Rates of reduction were measured in basic condition and in solvent system consisting of 4 parts of isopropyl alcohol and 1 part of water by volume. Second order rate constants were obtained for these reactions. When the ratio of [$OH^-$] to [$BH_4^-$] becomes large the observed rate constants ($K_{obs}$) decrease by a small factor. Reaction scheme and rate law are discussed. Bronsted ${\alpha}(=\frac{d\;In\;k}{d\;In\;K})$ obtained by using the value of equilibrium constant K, which was obtained previously, was not 0. Instead, a value of 0.36 was obtained which indicated that the reduction by borohydride was structure-dependent according to the Marcus formalism even though the reaction rate was close to the diffusion limit.

염화알루미늄 존재하에서의 수소화붕소나트륨과 대표적 유기화합물과의 반응 (Reaction of Representative Organic Compounds with Sodium Borohydride in the Presence of Aluminum Chloride)

  • 윤능민;이호준;정진순
    • 대한화학회지
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    • 제17권4호
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    • pp.275-285
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    • 1973
  • 유기화합물의 선택환원에 필요한 자료를 얻기 위하여 수소화붕소나트륨과 염화알루미늄의 3:1 혼합물의 테트라히드로푸란 용액에서의 환원성을 규명하였다. 49개의 대표적 유기화합물을 골라 이시약과 실온에서 작용하여 대략의 반응속도와 정량관계를 알아보았다. 테트라히드로푸란 용액에서 염화알루미늄 1몰에 수소화붕소나트륨 3몰을 가하면 현탁용액이 생기는데 수소화붕소나트륨 보다는 훨씬 환원성이 강하다. 알데히드와 케톤은 한시간 이내에 빨리 환원되고 아실유도체는 서서히 그러나 카르복시산은 매우 느리게 환원되었다. 에스테르, 락톤, 에폭시드는 수소화붕소나트륨이나 보란보다 훨씬 빨리 환원되었다. 삼차 아미드는 서서히 환원되었으나 일차 아미드는 수소는 발생하지만 환원은 거의 일어나지 않았다. 벤조니트릴은 30분에 환원이 완결되었으나 카프로니트릴은 느리게 환원되었다. 니트로화합물, 이황화물, 술폰등은 이 시약과 반응하지 않으나 아조, 아족시, 옥심기는 서서히 반응하고 이소시안산페닐은 도중단계까지만 환원되었다 올레핀은 쉽게 수소화붕소화 반응을 하였다.

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