H2 solubility in methanol in the presence of CO2 and O2

Hydrogen solubility in methanol, (methanol + carbon dioxide) and (methanol + carbon dioxide + oxygen) was measured and correlated at different temperatures (268 < T/K < 288) and pressures (0.37 < P/MPa < 3.5). Hydrogen content in the liquid phase was measured using a gas absorption method and Fugatron HYD-100 instrument. Experiments were performed in a fixed volume cell at constant temperature and hydrogen content was varied with subsequent loadings in the cell environment. At all conditions investigated a linear relation between hydrogen partial pressure and concentration was observed. Results were correlated and generalized as Henry’s constants for H2, as a function of temperature and CO2/methanol overall ratio. Correlation and generalization of the measurements was provided through a thermodynamic model, based on Peng–Robinson equation of state with van der Waals mixing rules and Boston–Mathias α-function. H2 solubility in methanol was confirmed to grow with temperature and amount of CO2; at constant H2 partial pressure, O2 does not affect H2 solubility.

► Experimental data of H2 solubility in methanol, with enhancement by CO2. ► Calibration of Peng–Robinson/Boston–Mathias equation of state. ► Maps and correlation for H2 Henry’s constants as a function of T and CO2/methanol ratio. ► Validation of in situ (liquid phase under pressure) H2 measurement instrument. ► Original data and correlation for H2O2 direct synthesis kinetic studies.