arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2108.06607cond-mat.mtrl-sci
收藏

Li-RHC体系储氢动力学行为的模拟:(I)吸收

Modeling the kinetic behavior of the Li-RHC system for energy-hydrogen storage : ( I ) absorption

A. M. Neves, J. Puszkiel, G. Capurso, J. M. Bellosta von Colbe, C. Milanese, M. Dornheim, T. Klassen, J. Jepsen

摘要:

锂硼反应性氢化物复合体系(Li-RHC)(2 LiH + MgB $_{2}$ / 2 LiBH $_{4}$ + MgH $_{2}$)是一种适合于储能应用的高温储氢材料。在此基础上,建立了一个综合的加氢反应气固动力学模型。根据吸收条件下的热力学测量,确定了系统的焓$Δ$ H和熵$Δ$ S分别为-34 $\pm$ 2 kJ $\cdot$ mol H $_{2}^{-1}$和-70 $\pm$ 3 J $\cdot$ K $^{-1}$ $\cdot$ mol H $_{2}^{-1}$.基于热力学行为评估,将动力学测量的条件设定在325 °C和412 °C之间以及15巴和50巴之间的范围内。动力学分析表明,加氢反应的限速步骤是一个一维的界面控制反应,其驱动力校正表观活化能为146 $\pm$ 3 kJ $\cdot$ mol H $_{2}^{-1}$ .应用动力学模型,计算作为压力和温度的函数的反应速率常数的依赖性,允许通过有限元方法(FEM)模拟来设计优化的氢/能量存储容器。

英文摘要:

The Lithium-Boron Reactive Hydride Composite System (Li-RHC) (2 LiH + MgB$_{2}$ / 2 LiBH$_{4}$ + MgH$_{2}$) is a high-temperature hydrogen storage material suitable for energy storage applications. Herein, a comprehensive gas-solid kinetic model for hydrogenation is developed. Based on thermodynamic measurements under absorption conditions, the system's enthalpy $Δ$H and entropy $Δ$S are determined to amount to -34 $\pm$ 2 kJ $\cdot$ mol H$_{2}^{-1}$ and -70 $\pm$ 3 J $\cdot$ K$^{-1}$ $\cdot$ mol H$_{2}^{-1}$, respectively. Based on the thermodynamic behavior assessment, the kinetic measurements' conditions are set in the range between 325 °C and 412 °C, as well as between 15 bar and 50 bar. The kinetic analysis shows that the hydrogenation rate-limiting-step is related to a one-dimensional interface-controlled reaction with a driving-force-corrected apparent activation energy of 146 $\pm$ 3 kJ $\cdot$ mol H$_{2}^{-1}$. Applying the kinetic model, the dependence of the reaction rate constant as a function of pressure and temperature is calculated, allowing the design of optimized hydrogen/energy storage vessels via finite element method (FEM) simulations.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑