Influence of dissolved hydrogen on the thermophysical properties of organic liquids

溶解氢对有机液体热物理性质的影响

• 批准号: 524349465
• 负责人: Professor Dr.-Ing. Andreas Paul Fröba
• 金额: --
• 依托单位: Erlangen Graduate School in Advanced Optical Technologies (SAOT)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/524349465?language=en
• 关键词: Influence; dissolved; hydrogen; thermophysical; properties

Hydrogen (H2) is a promising energy carrier for the future energy supply. In many H2-based technologies considered nowadays, H2 is in contact with organic liquids at vapor-liquid equilibrium (VLE) conditions. To obtain a fundamental understanding of the fluid behavior of mixtures of organic liquids with dissolved H2, detailed knowledge on their thermophysical properties as a function of temperature T, pressure p, and composition is required, yet often lacking or insufficient. The main objective of the proposed research project is to identify the influence of dissolved H2 on various thermophysical properties of organic liquids, where the properties are mainly relevant for the characterization of the transport of heat, mass, and momentum. For this, the H2 solubility and interfacial tension as well as the density, dynamic viscosity, thermal diffusivity, and Fick diffusion coefficients in the liquid phase of binary and ternary mixtures of organic liquids containing H2 at VLE should be determined via experimental and theoretical studies. The proposed representatives of different organic liquid classes complement the few already examined systems and allow to analyze the transferability of findings between the classes. Linear and branched alkanes, their oxygenated derivates given by polyvalent alcohols and poly(oxymethylene) dimethyl ethers as well as mono- or bicyclic hydrogenated and dehydrogenated hydrocarbons enable to cover wide ranges of the physicochemical features in terms of size, structure, and polarity and, thus, also of the absolute property values. Conventional methods as well as dynamic light scattering (DLS), the latter applied to the liquid bulk of fluids and at their phase boundaries within the same sample cell, should provide an accurate experimental database of the thermophysical properties for T and p up to 473 K and 10 MPa. Moreover, the DLS measurements promise to shed light on relations between the experimental results and the theory of diffusion in ternary mixtures involving H2. The macroscopic properties should be connected with the molecular characteristics of the organic solvents and the H2-influenced fluid structure studied by Raman spectroscopy and equilibrium molecular dynamics (EMD) simulations. The latter are planned to be used for selected representatives of each class, where corresponding force fields should be optimized mainly with respect to the T-dependent liquid density of the pure solvents and the H2 solubility. The focus of the EMD simulations lies on the analysis of the molecular H2 and solvent arrangement in the liquid phase and at the interface. The correspondingly developed picture and the available data should lead to the description of the impact of H2 on the thermophysical properties of interest in its mixtures with organic liquids as a function of temperature, pressure, and solvent composition in form of suitable correlations.

氢(H2)是未来能源供应的一种很有前途的能源载体。在当今考虑的许多氢气技术中，氢气在汽液平衡条件下与有机液体接触。为了从根本上了解有机液体与溶解氢气的混合物的流体行为，需要关于它们的热物理性质随温度T、压力p和组成的函数的详细知识，但通常缺乏或不足。该研究项目的主要目标是确定溶解氢对有机液体的各种热物理性质的影响，这些性质主要与热、质量和动量的传输特性有关。为此，应通过实验和理论研究确定含氢有机液体二元和三元混合物在汽液平衡时的溶解度和界面张力，以及液体的密度、动态粘度、热扩散系数和Fick扩散系数。拟议的不同有机液体类别的代表补充了已审查的几个系统，并允许分析结果在类别之间的可转移性。直链烷烃和支链烷烃，其由多价醇和聚二甲基醚给出的含氧衍生物，以及单环或双环氢化和脱氢碳氢化合物能够在大小、结构和极性方面覆盖广泛的物理化学特征，从而也能够覆盖绝对性质值的范围。传统方法和动态光散射(DLS)--后者应用于流体的液体体相界面和同一样品池内的相界面--应当提供高达473K和10 Mpa的T和p的精确的热物理性质的实验数据库。此外，DLS测量有望阐明实验结果与含氢的三元混合物中扩散理论之间的关系。宏观性质应与有机溶剂的分子特性以及用拉曼光谱和平衡分子动力学(EMD)模拟研究的受H2影响的流体结构有关。后者计划用于每一类的选定代表，其中相应的力场应主要根据纯溶剂的液体密度和H2的溶解度进行优化。EMD模拟的重点是分析氢分子在液体相中和界面上的排列以及溶剂的排列。相应的展开图和现有数据应以适当的关联式描述氢气对其与有机液体混合物中感兴趣的热物理性质的影响，作为温度、压力和溶剂组成的函数。