Correlation to predict solubility of hydrogen and carbon monoxide in heavy paraffins

The Fischer–Tropsch (FT) reactor and hydrocracker, which are important elements of a synthetic liquid fuel process, are multi-phase reactors having gas–solid–liquid reactions involving H2 and/or CO. To predict the reactor performance, it is therefore important for simulation models used in the techno-economic or feasibility studies of such processes to accurately capture the solubility of H2 and CO in the reactant–product mixture. This poses challenges in terms of the asymmetric nature of the mixture and accurate characterization of the components involved. Using solubility experimental data and validated component characterization equations from literature, correlations to determine the Peng–Robinson binary interaction parameters and hence, predict the solubility of H2 and CO are presented. These binary interaction parameter correlations are expressed as a function of the solvent carbon number and temperature.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► BIPs for individual binary pairs regressed to develop a solubility correlation. ► Solubility correlation predicts the solubility of H2 and CO in n-paraffin solvents. ► Temperature and carbon number dependency captured using PR EoS. ► Validated using data for a mixture of H2 and CO in C28. ► Increase in solubility with temperature, pressure and molecular weight predicted.