合成ガスから軽量オレフィンへの触媒変換における活性選択性トレードオフの解消
Feng Jiao1,2, Bing Bai1,2, Gen Li1,2
1State Key Laboratory of Catalysis, 2011-Collaborative Innovation Center of Chemistry for Energy Materials, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
Science (New York, N.Y.)
|May 18, 2023
まとめ
研究者は,シンガスを軽量オレフィンに変換する新しい触媒を開発し,高い選択性と生産性を達成しました. この画期的な発見は 望ましい反応と望ましくない副作用を 区別することで 触媒の重要な課題を克服しました
科学分野:
- カタリシス
- 材料科学
- 化学工学
背景:
- 触媒反応において高い選択性と活性性を同時に達成することは,依然として重要な課題である.
- 合成ガスを軽量オレフィンに直接変換することは化学原料の生産に不可欠であるが,しばしば選択性が低い.
- 望ましい製品を消費する二次反応を制御することは,全体的な収穫の改善の鍵です.
研究 の 目的:
- 触媒反応における二次反応から標的反応を切り離す戦略を示す.
- 直接合成ガスの変換による軽量オレフィンの選択性と産出量を向上させる.
- OXZEO触媒コンセプトにおけるゲルマニウム置換AlPO-18の役割を調査する.
主な方法:
- ゲルマニウム置換されたAlPO-18を金属酸化ゼオライト (OXZEO) 触媒枠に組み込む.
- 触媒の活性と選択性を調節するために,ブロンステッド酸の強さを調節する.
- 中間物質と製品の形成と消費を理解するために反応経路を分析する.
主要な成果:
- 炭化水素の間で 83% の軽量オレフィン選択性を達成した.
- 炭素一酸化物の同時変換を 85% 達成した.
- 前例のない48%の軽量オレフィン産出率を達成し,以前の産出率 (≤27%) を大幅に上回りました.
結論:
- ブレンステッド酸のサイト強度を弱めると,オレフィン形成のための標的型炭素-炭素結合が強化されます.
- 望ましい反応を二次反応から分離することは,光オレフィン産量を最大化するために非常に重要です.
- ゲルマニウム置換AlPO-18を用いたOXZEO触媒は,効率的な合成ガス変換のための有望な経路を提供します.
さらに関連する動画
関連する概念動画
02:17Reduction of Alkenes: Asymmetric Catalytic Hydrogenation
3.4K
Catalytic hydrogenation of alkenes is a transition-metal catalyzed reduction of the double bond using molecular hydrogen to give alkanes. The mode of hydrogen addition follows syn stereochemistry.
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
3.4K
02:13Reduction of Alkenes: Catalytic Hydrogenation
12.2K
Alkenes undergo reduction by the addition of molecular hydrogen to give alkanes. Because the process generally occurs in the presence of a transition-metal catalyst, the reaction is called catalytic hydrogenation.
Metals like palladium, platinum, and nickel are commonly used in their solid forms — fine powder on an inert surface. As these catalysts remain insoluble in the reaction mixture, they are referred to as heterogeneous catalysts.
The hydrogenation process takes place on the...
Metals like palladium, platinum, and nickel are commonly used in their solid forms — fine powder on an inert surface. As these catalysts remain insoluble in the reaction mixture, they are referred to as heterogeneous catalysts.
The hydrogenation process takes place on the...
12.2K
02:24Reduction of Alkynes to cis-Alkenes: Catalytic Hydrogenation
7.8K
Introduction
Like alkenes, alkynes can be reduced to alkanes in the presence of transition metal catalysts such as Pt, Pd, or Ni. The reaction involves two sequential syn additions of hydrogen via a cis-alkene intermediate.
Like alkenes, alkynes can be reduced to alkanes in the presence of transition metal catalysts such as Pt, Pd, or Ni. The reaction involves two sequential syn additions of hydrogen via a cis-alkene intermediate.
7.8K
02:50Catalysis
27.1K
The presence of a catalyst affects the rate of a chemical reaction. A catalyst is a substance that can increase the reaction rate without being consumed during the process. A basic comprehension of a catalysts’ role during chemical reactions can be understood from the concept of reaction mechanisms and energy diagrams.
27.1K
02:17Regioselectivity of Electrophilic Additions to Alkenes: Markovnikov's Rule
14.4K
If a set of reactants can yield multiple constitutional isomers, but one of the isomers is obtained as the major product, the reaction is said to be regioselective. In such reactions, bond formation or breaking is favored at one reaction site over others.
The hydrohalogenation of an unsymmetrical alkene can yield two haloalkane products, depending on which vinylic carbon takes up the halogen. However, one product usually predominates, where hydrogen adds to the vinylic carbon bearing the...
The hydrohalogenation of an unsymmetrical alkene can yield two haloalkane products, depending on which vinylic carbon takes up the halogen. However, one product usually predominates, where hydrogen adds to the vinylic carbon bearing the...
14.4K
01:28Reduction of Benzene to Cyclohexane: Catalytic Hydrogenation
4.7K
Unlike the easy catalytic hydrogenation of an alkene double bond, hydrogenation of a benzene double bond under similar reaction conditions does not take place easily. For example, in the reduction of stilbene, the benzene ring remains unaffected while the alkene bond gets reduced. Hydrogenation of an alkene double bond is exothermic and a favorable process. In contrast, to hydrogenate the first unsaturated bond of benzene, an energy input is needed; that is, the process is endothermic. This is...
4.7K