碳酸盐促进的混合稀土氧化物作为氧化合甲的一般化策略,具有特殊产量
Kun Zhao1,2, Yunfei Gao3, Xijun Wang4
1North Carolina State University, Campus Box 7905, Raleigh, NC, USA.
Nature communications
|November 27, 2023
概括
这项研究引入了新的碳酸涂层稀土氧化物催化剂,用于直接转化甲. 这些催化剂在实际条件下通过甲的氧化合来实现高碳 (C2+) 的高产量.
科学领域:
- 催化剂是一种催化剂.
- 材料科学 材料科学 材料科学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 通过氧化合 (OCM) 直接将甲转化为更高碳化合物具有挑战性,原因是产量低,温度高以及在实际压力下性能问题.
- 现有的OCM催化剂在工业相关条件下经常难以提高效率和稳定性.
研究的目的:
- 使用化学循环方法开发高效的氧化还原催化剂,用于甲的氧化合 (OCM).
- 研究用于OCM的Li2CO3涂层混合稀土氧化物的性能和潜在机制.
主要方法:
- 合成和表征Li2CO3涂层混合稀土氧化物催化剂.
- 在不同甲部分压力和温度下的OCM反应中评估催化剂性能.
- 在现场表征技术和量子化学计算以阐明反应机制.
主要成果:
- 使用Li2CO3涂层混合稀土氧化物,达到高达30.6%的单通C2+产量.
- 在700°C和甲部分压力高达1.4 atm时,证明了稳定的催化剂性能.
- 确定了混合氧化物核心和Li2CO3外的协同作用,以及Pr氧化状态和过氧化物形成的重要性.
结论:
- 在化学循环条件下,2CO3涂层混合稀土氧化物是OCM高效的氧化还原催化剂.
- Pr4+含量与碳化合物产量之间的相关性为这些催化剂提供了优化策略.
- 这项工作将直接甲转化技术推向实际应用.
更多相关视频
相关概念视频
Alkenes via Reductive Coupling of Aldehydes or Ketones: McMurry Reaction
1.9K
The radical dimerization of ketones or aldehydes gives vicinal diols through a pinacol coupling reaction. However, the behavior of titanium metals used for the reaction as a source of electrons is unusual. When the reaction is carried out in the presence of titanium, diols can be isolated at low temperatures. Else titanium further reacts with diols, forming alkenes through the McMurry reaction.
1.9K
Oxidation of Alkenes: Syn Dihydroxylation with Potassium Permanganate
11.6K
Alkenes can be dihydroxylated using potassium permanganate. The method encompasses the reaction of an alkene with a cold, dilute solution of potassium permanganate under basic conditions to form a cis-diol along with a brown precipitate of manganese dioxide.
11.6K
Oxidation of Alkenes: Syn Dihydroxylation with Osmium Tetraoxide
10.3K
Alkenes are converted to 1,2-diols or glycols through a process called dihydroxylation. It involves the addition of two hydroxyl groups across the double bond with two different stereochemical approaches, namely anti and syn. Dihydroxylation using osmium tetroxide progresses with syn stereochemistry.
10.3K
Radical Oxidation of Allylic and Benzylic Alcohols
2.0K
Activated manganese(IV) oxide can selectively oxidize allylic and benzylic alcohols via a radical intermediate mechanism. Primary allylic alcohols are oxidized to aldehydes, while secondary allylic alcohols yield ketones. The redox reaction of potassium permanganate with an Mn(II) salt such as manganese sulfate (under either alkaline or acidic conditions), followed by thorough drying, yields the oxidizing agent: activated MnO2. While MnO2 is insoluble in the solvents used for the reaction, the...
2.0K
Hydroboration-Oxidation of Alkenes
8.3K
In addition to the oxymercuration–demercuration method, which converts the alkenes to alcohols with Markovnikov orientation, a complementary hydroboration-oxidation method yields the anti-Markovnikov product. The hydroboration reaction, discovered in 1959 by H.C. Brown, involves the addition of a B–H bond of borane to an alkene giving an organoborane intermediate. The oxidation of this intermediate with basic hydrogen peroxide forms an alcohol.
8.3K
Alcohols from Carbonyl Compounds: Reduction
10.4K
Reduction is a simple strategy to convert a carbonyl group to a hydroxyl group. The three major pathways to reduce carbonyls to alcohols are catalytic hydrogenation, hydride reduction, and borane reduction.
Catalytic hydrogenation is similar to the reduction of an alkene or alkyne by adding H2 across the pi bond in the presence of transition metal catalysts like Raney Ni, Pd–C, Pt, or Ru. Aldehydes and ketones can be reduced by this method, often under mild to moderate heat (25–100°C) and...
Catalytic hydrogenation is similar to the reduction of an alkene or alkyne by adding H2 across the pi bond in the presence of transition metal catalysts like Raney Ni, Pd–C, Pt, or Ru. Aldehydes and ketones can be reduced by this method, often under mild to moderate heat (25–100°C) and...
10.4K


