对一些水/二元系统的三相平衡的计算机模拟
Arturo Elías-Domínguez1, Juan F J Alvarado2, Fernando Pérez-Villaseñor1
1Facultad de Ciencias Básicas, Ingeniería y Tecnología, Universidad Autónoma de Tlaxcala, Ángel Solana S/N, San Luis Apizaquito, Apizaco, Tlaxcala CP 90341, México.
The journal of physical chemistry. B
|May 10, 2024
概括
本研究详细介绍了使用先进模拟的水和n-alkane系统的蒸汽-液体-液体平衡 (VLLE). 结果准确地预测了三相平衡特性,为这些非理想系统提供了新的见解.
科学领域:
- 物理化学 物理化学
- 化学工程是化学工程的重要组成部分.
- 计算化学的计算化学
背景情况:
- 在水/n-alkane系统中,蒸汽-液体-液体平衡 (VLLE) 是至关重要的,但由于非理想的行为而具有挑战性.
- 之前的研究还没有在广泛的温度范围内对这些特定的二进制系统进行广泛的VLLE探索.
研究的目的:
- 计算和分析水/n-,水/n-,水/n-,水/n-,以及水/n-二进制系统的三相平衡特性.
- 为了首次详细研究这些高度不理想的系统中的VLLE现象.
- 根据现有的实验数据验证模拟结果.
主要方法:
- 利用NVT-Gibbs组合 (三个模拟盒) 与配置偏差蒙特卡洛方法相结合,用于计算机模拟.
- 采用特定的分子潜力模型和详细的模拟参数来准确计算平衡特性.
- 对实验数据相关的广泛温度范围内的模拟系统.
主要成果:
- 成功计算了平衡中的三个共存相的密度,组成和潜在能量.
- 模拟结果与研究系统的现有实验数据之间有很好的一致性.
- 亚临界密度与缩放规律保持一致,使得可以估计上临界终点温度和密度.
结论:
- 采用的模拟方法准确地捕捉了水/n-alkane系统的复杂VLLE行为.
- 该研究提供了对这些非理想混合物的三相平衡性质的详细了解.
- 结果证实了模拟方法在类似系统中预测VLLE的可靠性.
更多相关视频
相关概念视频
02:39Phase Diagrams
40.6K
A phase diagram combines plots of pressure versus temperature for the liquid-gas, solid-liquid, and solid-gas phase-transition equilibria of a substance. These diagrams indicate the physical states that exist under specific conditions of pressure and temperature and also provide the pressure dependence of the phase-transition temperatures (melting points, sublimation points, boiling points). Regions or areas labeled solid, liquid, and gas represent single phases, while lines or curves represent...
40.6K
01:21Chemical Equilibria: Systematic Approach to Equilibrium Calculations
680
Equilibrium calculations for systems involving multiple equilibria are often complex. For example, to calculate the solubility of a sparingly soluble salt in an aqueous solution in the presence of a common ion, one must consider all the equilibria in this solution. Calculations for these systems can be complicated and tedious, so a systematic approach with a series of steps is often helpful. The process is detailed below.
The first step is to identify all the chemical reactions involved, The...
The first step is to identify all the chemical reactions involved, The...
680
01:01Distillation: Vapor–Liquid Equilibria
2.8K
Distillation is a separation technique that takes advantage of the boiling point properties of disparate elements in a mixture. To perform distillation, we begin by heating a miscible mixture of two liquids with a significant difference in boiling points (at least 20°C). As the solution heats up and reaches the bubble point of the more volatile component, some molecules of the more volatile component transition into the gas phase and travel upward into the condenser, which is a glass tube...
2.8K
01:19Phase Diagram
5.8K
The phase of a given substance depends on the pressure and temperature. Thus, plots of pressure versus temperature showing the phase in each region provide considerable insights into the thermal properties of substances. Such plots are known as phase diagrams. For instance, in the phase diagram for water (Figure 1), the solid curve boundaries between the phases indicate phase transitions (i.e., temperatures and pressures at which the phases coexist).
5.8K
02:05Entropy and Solvation
7.0K
The process of surrounding a solute with solvent is called solvation. It involves evenly distributing the solute within the solvent. The rule of thumb for determining a solvent for a given compound is that like dissolves like. A good solvent has molecular characteristics similar to those of the compound to be dissolved. For example, polar solutions dissolve polar solutes, and apolar solvents dissolve apolar solutes. A polar solvent is a solvent that has a high dielectric constant (ϵ...
7.0K
02:20Dynamic Equilibrium
51.5K
A reversible chemical reaction represents a chemical process that proceeds in both forward (left to right) and reverse (right to left) directions. When the rates of the forward and reverse reactions are equal, the concentrations of the reactant and product species remain constant over time and the system is at equilibrium. A special double arrow is used to emphasize the reversible nature of the reaction. The relative concentrations of reactants and products in equilibrium systems vary greatly;...
51.5K