High-pressure gas solubility in multicomponent solvent systems for hydroformylation. Part II: Syngas solubility

Abstract

High-pressure solubility of syngas with a molar ratio of hydrogen (H2) and carbon monoxide (CO) of 1:1 was investigated in various solvents like n-decane, dimethylformamide (DMF), 1-dodecene and n-dodecanal as well as in mixtures of n-decane and DMF and in a mixture of 1-dodecene, n-dodecanal, n-decane and DMF at temperatures between 302K and 367K and at pressures of up to 14MPa. Moreover, the H2 solubility in 1-dodecene and n-dodecanal was measured in the same pressure and temperature range. The solubility measurements were performed in a high-pressure volume-variable view cell using a visual synthetic method. For modeling and prediction of the gas solubility (H2, CO, and syngas (H2/CO)) in the considered solvents, the Perturbed Chain Statistical Associating Fluid Theory (PC-SAFT) was used. The systems containing one gas (H2 or CO) and one solvent were modeled accurately by applying temperature-independent binary interaction parameters (kij's). These kij's were used to predict the syngas solubility in pure solvents and their mixtures without further adjustments. The kij between H2 and CO was always set to zero. The results showed that PC-SAFT is able to predict the syngas solubility in pure solvents with an average relative deviation of 3.1–12.0%. Syngas solubility in the n-decane/DMF mixture was predicted with a deviation of 7.2%.