Despite H₂ being a clean and high-energy carrier, it poses storage and transportation problems, due to high liquefaction pressure, low volumetric density, as well as low boiling point. Consequently, research efforts are focused on the search for sustainable alternative H₂ storage technology. In this study, the thermodynamic analyses of liquid organic hydrogen carriers (LOHCs), which utilize the reversible methylcyclohexane–toluene system (MTS) for H₂ storage, are investigated. The study employs the Gibbs free energy minimization procedure by treating the non-ideal behavior of the participating species using the Soave–Redlich–Kwong https://www.e-education.psu.edu/png520/m10_p5.html (SRK) equation of states. The “fmincon” optimization algorithm in MATLAB (R2016 version) was employed to find the Gibbs free energy minima. The study reveals close to 100% equilibrium conversion of methylcyclohexane (MCH), with about 99% yield of H₂at325^oC and 1 bar. In the literature report, PtSn/Mg–Al and Pt/Ce_1.4-Mg–Al catalysts showed operability close to the equilibrium conversion. On the other hand, toluene hydrogenation is favored by low temperature and high pressure. The thermodynamic calculation reveals close to 100% equilibrium conversion at 100 °C and 1 bar, which is not achievable by existing catalytic systems due to kinetic limitations. Much improvement is desirable in catalyst design for this process operating at atmospheric pressure, suggested by this thermodynamic study and clearly, a high-pressure–low-temperature system is desirable for the hydrogenation reaction.

尽管 H ₂是一种清洁和高能量的载体，但由于液化压力高、体积密度低以及沸点低，因此存在储存和运输问题。因此，研究工作的重点是寻找可持续的替代 H ₂存储技术。在本研究中，液态有机氢载体 (LOHC) 的热力学分析利用可逆的甲基环己烷-甲苯系统 (MTS) 处理 H ₂存储，进行调查。该研究通过使用 Soave-Redlich-Kwong https://www.e-education.psu.edu/png520/m10_p5.html (SRK) 方程处理参与物种的非理想行为，采用吉布斯自由能最小化程序的状态。使用MATLAB（R2016版本）中的“fmincon”优化算法来寻找吉布斯自由能最小值。该研究表明，甲基环己烷 (MCH) 的平衡转化率接近 100%，在325 ^o C 和 1 bar 下，H _{2 的}产率约为 99% 。在文献报道中，PtSn/Mg-Al 和 Pt/Ce _1.4-Mg-Al 催化剂表现出接近平衡转化率的可操作性。另一方面，低温高压有利于甲苯加氢。热力学计算表明，在 100 °C 和 1 bar 下，平衡转化率接近 100%，由于动力学限制，现有催化系统无法实现。该热力学研究表明，对于在大气压下操作的该过程的催化剂设计需要进行大量改进，并且显然，高压 - 低温系统对于氢化反应是可取的。