盐对二氧化碳2减少产品分布在近极电解质中的影响
Iris Burgers1, Boris Wortmann1, Amanda C Garcia2
1Process and Energy Department, Faculty of Mechanical Engineering, Delft University of Technology, Delft, Zuid-Holland, 2628 CB, The Netherlands.
概括
使用铜电极的非水性电化学二氧化碳减排被电解质中的较大阴离子增强,促进了乙烯的生产. 较大的离子会产生更水的表面,稳定碳化合物形成的关键中间体.
科学领域:
- 电化学 电化学 电化学
- 材料科学 材料科学 材料科学
- 催化剂是一种催化剂.
背景情况:
- 电化学二氧化碳减排是一种有前途的技术,用于将二氧化碳转化为有价值的化学物质.
- 与水系统相比,非水性电解质的二氧化碳溶解度更高,可能提高效率.
- 铜 (Cu) 是减少二氧化碳的关键催化剂,但其选择性可能受到电解质成分的影响.
研究的目的:
- 用多晶铜研究不同盐对二氧化碳减排产品分布的影响.
- 了解碳酸 (PC) 中的离子体大小和离子类型如何影响选择性.
- 确定最大限度地减少二氧化碳的碳化合物形成的最佳条件.
主要方法:
- 电化学实验包括 chronoamperometry. 电化学实验包括 chronoamperometry. 电化学实验包括 chronoamperometry.
- 在现场的里埃变换红外光谱 (FTIR) 用于监测反应中间体.
- 九种不同盐的系统变化,在碳酸中具有不同的阴离子 (四乙,四乙,四乙) 和阴离子 (化物,四甲,六甲).
主要成果:
- 阴离子大小显著影响二氧化碳减排的选择性,较大的阴离子促进碳化合物形成.
- 一个更疏水的电极表面,通过更大的阴离子和较弱的水化来实现,稳定了CO2基离子.
- 在PC中观察到0.7M四甲化 (THACl) 的碳化合物形成最高.
- 在现场FTIR建议通过COH中间二分化而不是C-C合来减少二氧化碳.
结论:
- 电解质盐的选择,特别是,对于控制非水性电化学二氧化碳减排的选择性至关重要.
- 更大,更疏水的子通过稳定关键中间体来增强乙烯的生产.
- 拟议的机制涉及COH二元化,在PC中高CO溶解度的支持下.
相关概念视频
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03:24Common Ion Effect
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01:20Chemical Equilibria: Redefining Equilibrium Constant
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The effect of an inert salt on the solubility of a sparingly soluble salt is known as the salt effect. The degree of the salt effect varies with the ionic strength of the solution, which in turn depends on the activity of the species in the solution. The activity is expressed as the product of concentration and the activity coefficient of the species.
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02:54Ions as Acids and Bases
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Salts with Acidic Ions
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Salts are ionic compounds composed of cations and anions, either of which may be capable of undergoing an acid or base ionization reaction with water. Aqueous salt solutions, therefore, may be acidic, basic, or neutral, depending on the relative acid-base strengths of the salt’s constituent ions. For example, dissolving the ammonium chloride in water results in its dissociation, as described by the equation:
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01:09Solubility Equilibria: Overview
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When a substance such as sodium chloride is added to water, it dissolves, forming an aqueous solution. The extent of dissolution is called solubility. The process of dissolution can exist in equilibrium, just like other chemical processes. Solubility equilibria are also called precipitation equilibria because the process of solubility can be reversible. The reverse of the solubility process is called precipitation.
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04:08Determining the pH of Salt Solutions
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