扩大CO2的溶剂:用于执行均的催化氧化过程的独特和多功能介质
Ming Wei1, Ghezai T Musie, Daryle H Busch
1Department of Chemical and Petroleum Engineering, University of Kansas, Lawrence, KS 66045-2223, USA.
Journal of the American Chemical Society
|March 14, 2002
概括
这项研究引入了CO2扩展溶剂,以实现更绿色的催化氧化. 这种新的方法通过增加氧的可溶性和改善反应中的催化剂性能,显著提高了氧化率.
科学领域:
- 绿色化学 绿色化学
- 催化剂是一种催化剂.
- 化学工程是化学工程的重要组成部分.
背景情况:
- 传统的有机溶剂给环境带来了担忧.
- 密度相二氧化碳 (CO2) 是一个有前途的绿色溶剂.
- 同质的催化氧化反应通常需要有效的氧气输送.
研究的目的:
- 开发一种新的方法,用于使用CO2扩展溶剂进行均的催化氧化.
- 为了提高氧化催化反应的反应速度和效率.
- 为了利用CO2作为辅溶剂的独特特性.
主要方法:
- 在中等压力下,高达80%的有机溶剂可以用密集相CO ((2) 替换.
- 创建用于催化反应的CO2膨胀溶剂介质.
- 使用过渡金属催化剂 (石基,铁) 进行氧化.
主要成果:
- 加入CO2增加了约100倍的O2溶解度.
- 与纯有机溶剂或超临界CO2相比,CO2扩张溶剂的氧化率高出1-2个数量级.
- 证明了和环素的成功同质氧化.
结论:
- 扩大CO2的溶剂为同质氧化催化提供了有效和更绿色的替代方案.
- 这种方法通过优化氧溶性和催化剂性能来显著提高反应效率.
- 该方法为可持续化学合成提供了一个可行的策略.
相关概念视频
Physical Properties Affecting Solubility
Solutions of Gases in Liquids
As for any solution, the solubility of a gas in a liquid is affected by the attractive intermolecular forces between solute and solvent species. Unlike solid and liquid solutes, however, there is no solute-solute intermolecular attraction to overcome when a gaseous solute dissolves in a liquid solvent since the atoms or molecules comprising a gas are far separated and experience negligible interactions. Consequently, solute-solvent interactions are the sole...
As for any solution, the solubility of a gas in a liquid is affected by the attractive intermolecular forces between solute and solvent species. Unlike solid and liquid solutes, however, there is no solute-solute intermolecular attraction to overcome when a gaseous solute dissolves in a liquid solvent since the atoms or molecules comprising a gas are far separated and experience negligible interactions. Consequently, solute-solvent interactions are the sole...
Catalysis
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.
Catalysis
Catalysis influences the rate of chemical reactions by providing an alternative reaction pathway with lower activation energy. A catalyst speeds up a reaction, but it is not consumed during the process. The fundamental principle of catalysis is the ability of a catalyst to alter the reaction mechanism, often introducing a more efficient pathway than the uncatalyzed process.In a catalyzed reaction, the catalyst participates directly in the reaction mechanism. It interacts with reactants to form...
Carbonation Shrinkage
Atmospheric CO2 penetrates the concrete's pores and, in the presence of moisture, forms carbonic acid, which then reacts with calcium hydroxide in the hydrated cement, forming calcium carbonate. This process reduces the concrete's volume and is termed carbonation shrinkage.
The concrete's permeability is slightly reduced as calcium carbonate produced during the reaction fills its pores. Furthermore, its strength is slightly enhanced as the water released during the reaction facilitates the...
The concrete's permeability is slightly reduced as calcium carbonate produced during the reaction fills its pores. Furthermore, its strength is slightly enhanced as the water released during the reaction facilitates the...
Carbon-dioxide Fixation
Carbon dioxide fixation in prokaryotes enables the assimilation of inorganic carbon into organic molecules, supporting biosynthetic pathways, sustaining ecosystems, and contributing to the global carbon cycle. It also has industrial applications in carbon capture and bioproduct synthesis. Autotrophic organisms rely on this process to utilize CO₂ as a carbon source in diverse environments.The Calvin CycleThe Calvin cycle is the most widespread carbon fixation mechanism, primarily used by...
Bioreactor Controls-II
In aerobic fermentations, oxygen is vital for microbial growth and metabolite production. Since air comprises only about 20% oxygen and the gas is poorly soluble in water—just 9 ppm at 20°C—supplying sufficient oxygen becomes a critical challenge, especially in high-demand processes like yeast growth or citric acid production. Even a fully saturated broth may offer only a few seconds of oxygen availability.To address this, sterile or scrubbed air is introduced into the fermentor via a sparger...


