Measurement and correlation of the solubility of Hydrogen in Acetophenone and 1-Methylnaphthalene

Hydrogen (H 2 ) solubility in liquid organic hydrogen carriers (LOHCs) is crucial for their widespread applications. This work investigates the solubility of H₂ x in two promising LOHCs: Acetophenone (APO) and 1-Methylnaphthalene (1-MN). Measurements were conducted using an isochoric saturation method within a temperature range of 293 to 363 K and pressures up to 5.8 MPa. The liquid densities ρ of APO and 1-MN, essential for characterizing H₂ solubility, were measured using a vibrating tube densitometer (DMA5000 M) at approximately 0.1 MPa. The experimental ρ for APO and 1-MN were compared with literature data and good agreement can be found. The Krichevsky-Kasarnovsky(K-K) equation was employed to correlate H₂ solubility x in APO and 1-MN, with deviations of mostly within 6 % and 10 %, respectively. Following, the behavior of H₂ solubility x concerning pressure along isothermal lines was analyzed. Finally, the thermodynamic parameter of dissolution of the two binary systems were studied. The enthalpy of dissolution is positive for all the systems, while the entropy of dissolution is negative. Under the same temperature, the Gibbs free energy of dissolution for the H₂ + APO system is smaller than that of the H₂ + 1-MN system.