一个以大小为依赖的理想溶液模型,用于在水性有机溶液中预测液体-固体相位平衡
Spencer P Alliston1, Chris Dames1, Matthew J Powell-Palm2,3,4
1Department of Mechanical Engineering, University of California, Berkeley, CA 94720.
概括
在水性有机溶液中预测相位平衡是通过修改的理想溶液理论来增强的. 考虑到分子尺寸差异,可以显著改善液体和点的预测.
科学领域:
- 物理化学 物理化学
- 解决方案热力学 解决方案热力学
- 材料科学 材料科学 材料科学
背景情况:
- 水性有机溶液的预测建模对于工业化学和冷保存至关重要.
- 目前的模型很难准确地预测液体-固体相位平衡,只使用散装特性.
- 通常需要直接测量或模拟,这限制了实际应用.
研究的目的:
- 开发一种改进的分析模型,用于预测有机水溶液中的相位平衡.
- 通过结合分子尺寸效应来增强理想溶液理论的预测能力.
- 提供一个更简单,更准确的方法,用于相位图预测.
主要方法:
- 修改的理想溶液理论,结合了混合的弗洛里式.
- 纳入摩尔和体积分数用于尺寸依赖的计算.
- 对水和十种有机溶液的二进制相图的预测.
主要成果:
- 取决于尺寸的模型显著超过了理想解决方案模型.
- 液体温度预测的平均误差降低了59% (至5.6K).
- 降低了45% (至9.7K) 的体温度的平均误差和43% (至4.7mol%) 的成分.
结论:
- 分子尺寸效应,特别是混合,在水性有机溶液相位行为中发挥主导作用.
- 修改后的模型提供了一种简单而强大的方法来预测相位平衡.
- 这项工作突显了溶液热力学中热效应的低估影响.
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