• 제목/요약/키워드: trivalent

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High Selective Oxidation of Alcohols Based on Trivalent Ion (Cr3+ and Co3+) Complexes Anchored on MCM-41 as Heterogeneous Catalysts

  • Shojaei, Abdollah Fallah;Rafie, Mahboubeh Delavar;Loghmani, Mohammad Hassan
    • Bulletin of the Korean Chemical Society
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    • 제33권8호
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    • pp.2748-2752
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    • 2012
  • Cr(III) and Co(III) complexes with acetylacetonate were anchored onto a mesoporous MCM-41 through Schiff condensation. The materials were characterized by XRD, FT-IR, BET, CHN and ICP techniques. Elemental analysis of samples revealed that one C=N bond was formed through Schiff condensation on MCM-41 surface. The catalysts were tested for the alcohol oxidations using t-butyl hydroperoxide (TBHP) and $H_2O_2$ as oxidant. The catalytic experiments were carried out at both room temperature and reflux condition. Various solvents such as dichloromethane, acetonitrile and water were examined in the oxidation of alcohols. Among the different solvents, catalytic activity is found more in acetonitrile. Further, the catalysts were recycled three times in the oxidation of alcohols and no major change in the conversion and selectivity is observed, which shows that the immobilized metal-acetylacetonate complexes are stable under the present reaction conditions.

三價稀土類元素의 溶媒推出上의 相乘效果 (Synergistic Effect in the Solvent Extraction of Trivalent Lanthanides by Neutral Phosphine Oxides)

  • 이진택
    • 대한화학회지
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    • 제7권4호
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    • pp.245-250
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    • 1963
  • TBPO와 TOPO와의 混合溶媒(稀釋制 : toluene)에 依한 三假狀態의 4f 稀土類元素의 抽出에 있어 相乘效果(synerigistic effect)가 나타남을 알았으며 이것은 各 單獨溶媒系에 있어서 生成抽出되는 $M(NO_3)_3\;(TBPO)_3$$M(NO_3)_3\;(TOPO)_3$型 外에 $M(NO_3)_3\;(TBPO)_2\;(TOPO)$型이 새로히 追加生成됨을 起因된 것으로 認定된다.

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희토류금속 착물의 합성과 전기화학적 거동 (제 2 보) (Synthesis and Electrochemical Behavior of Rare Earths Metal Complexes)

  • 최칠남;정오진;윤석진;김준태
    • 대한화학회지
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    • 제34권3호
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    • pp.280-287
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    • 1990
  • 란탄나이드 3가 [Sm(Ⅲ), Tb(Ⅲ), and Yb(Ⅲ)]와 유기리간드들의 착물을 비수용매 속에서 전기화학적인 DC 및 DP 폴라로그래피 그리고 CV방법으로 조사하였다. 란탄나이드 3가 착물들은 Ag/AgCl 전극에서 이들 환원 peak는$ E_{pc}$ = -0.16 V, -0.35 V, -0.14 V와 그리고 -0.03 V의 비가역적인 일전자환원 과정이었고, 무거운 란탄나이드의 거동은 원자번호가 증가함에 따라서 안정도상수는 Sm > Tb > Ho > Yb순서로 감소하였다

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