Measurement and modelling of high pressure bubble- and dew-point data for the CO2+1-decanol+3,7-dimethyl-1-octanol system

摘要

This work aims to characterise the solute-solute interaction which occurs in a ternary system containing CO2 with solutes, 1-decanol and 3,7-dimethyl-1-octanol and to compare the ability of the RK-ASPEN and CPA models, available within the Aspen Plus (R) software, to predict solubility data for this system. Bubble and dew-point data were therefore measured for three 1-decanol + 3,7-dimethyl-1-octanol mixtures in CO2, at temperatures between 308 K and 358 K, with pressures up to 27.5 MPa and with total solute mass fractions ranging from 0.605 to 0.015. The data were measured using the static, synthetic visual phase detection method. The measured data revealed that significant solute-solute interactions exist in the ternary system. Furthermore, in mixtures where 1-decanol dominated the mixture composition, these interactions resulted in the occurrence of a temperature inversion. The bubble- and dew-point data for the system were predicted using the RK-ASPEN and CPA models. The models were fitted using literature and experimental data. Comparison of the prediction obtained using the RK-ASPEN and CPA models indicated that the solubility data of the ternary system can better be described using the polar-based RK-ASPEN equation of state model. (C) 2019 Elsevier B.V. All rights reserved.